From 4226fada45a83ad56e91ce7638d17d12fecec8ca Mon Sep 17 00:00:00 2001
From: Zoranzoki21 <zorandori4444@gmail.com>
Date: Sun, 21 Apr 2019 01:34:48 +0200
Subject: [PATCH] Split parser related files to have one class in one file

Change-Id: I36b26609ccb3f135a22961b32a46cdc06603b3e4
---
 .phpcs.xml                               |    3 -
 autoload.php                             |   38 +-
 includes/parser/PPCustomFrame_DOM.php    |   70 ++
 includes/parser/PPCustomFrame_Hash.php   |   70 ++
 includes/parser/PPDPart.php              |   39 +
 includes/parser/PPDPart_Hash.php         |   36 +
 includes/parser/PPDStack.php             |  113 ++
 includes/parser/PPDStackElement.php      |  129 ++
 includes/parser/PPDStackElement_Hash.php |   73 ++
 includes/parser/PPDStack_Hash.php        |   34 +
 includes/parser/PPFrame.php              |  204 +++
 includes/parser/PPFrame_DOM.php          |  631 ++++++++++
 includes/parser/PPFrame_Hash.php         |  613 +++++++++
 includes/parser/PPNode.php               |  112 ++
 includes/parser/PPNode_DOM.php           |  188 +++
 includes/parser/PPNode_Hash_Array.php    |   77 ++
 includes/parser/PPNode_Hash_Attr.php     |   92 ++
 includes/parser/PPNode_Hash_Text.php     |   90 ++
 includes/parser/PPNode_Hash_Tree.php     |  369 ++++++
 includes/parser/PPTemplateFrame_DOM.php  |  198 +++
 includes/parser/PPTemplateFrame_Hash.php |  202 +++
 includes/parser/Preprocessor.php         |  276 ----
 includes/parser/Preprocessor_DOM.php     | 1228 ------------------
 includes/parser/Preprocessor_Hash.php    | 1456 ----------------------
 24 files changed, 3359 insertions(+), 2982 deletions(-)
 create mode 100644 includes/parser/PPCustomFrame_DOM.php
 create mode 100644 includes/parser/PPCustomFrame_Hash.php
 create mode 100644 includes/parser/PPDPart.php
 create mode 100644 includes/parser/PPDPart_Hash.php
 create mode 100644 includes/parser/PPDStack.php
 create mode 100644 includes/parser/PPDStackElement.php
 create mode 100644 includes/parser/PPDStackElement_Hash.php
 create mode 100644 includes/parser/PPDStack_Hash.php
 create mode 100644 includes/parser/PPFrame.php
 create mode 100644 includes/parser/PPFrame_DOM.php
 create mode 100644 includes/parser/PPFrame_Hash.php
 create mode 100644 includes/parser/PPNode.php
 create mode 100644 includes/parser/PPNode_DOM.php
 create mode 100644 includes/parser/PPNode_Hash_Array.php
 create mode 100644 includes/parser/PPNode_Hash_Attr.php
 create mode 100644 includes/parser/PPNode_Hash_Text.php
 create mode 100644 includes/parser/PPNode_Hash_Tree.php
 create mode 100644 includes/parser/PPTemplateFrame_DOM.php
 create mode 100644 includes/parser/PPTemplateFrame_Hash.php

diff --git a/.phpcs.xml b/.phpcs.xml
index b60a3aff66..a9c658a6b8 100644
--- a/.phpcs.xml
+++ b/.phpcs.xml
@@ -189,9 +189,6 @@
 			Whitelist existing violations, but enable the sniff to prevent
 			any new occurrences.
 		-->
-		<exclude-pattern>*/includes/parser/Preprocessor_DOM\.php</exclude-pattern>
-		<exclude-pattern>*/includes/parser/Preprocessor_Hash\.php</exclude-pattern>
-		<exclude-pattern>*/includes/parser/Preprocessor\.php</exclude-pattern>
 		<exclude-pattern>*/maintenance/dumpIterator\.php</exclude-pattern>
 		<exclude-pattern>*/maintenance/Maintenance\.php</exclude-pattern>
 		<exclude-pattern>*/maintenance/findDeprecated\.php</exclude-pattern>
diff --git a/autoload.php b/autoload.php
index 35137ab943..13037ff98e 100644
--- a/autoload.php
+++ b/autoload.php
@@ -1050,28 +1050,28 @@ $wgAutoloadLocalClasses = [
 	'PHPVersionCheck' => __DIR__ . '/includes/PHPVersionCheck.php',
 	'PNGHandler' => __DIR__ . '/includes/media/PNGHandler.php',
 	'PNGMetadataExtractor' => __DIR__ . '/includes/media/PNGMetadataExtractor.php',
-	'PPCustomFrame_DOM' => __DIR__ . '/includes/parser/Preprocessor_DOM.php',
-	'PPCustomFrame_Hash' => __DIR__ . '/includes/parser/Preprocessor_Hash.php',
-	'PPDPart' => __DIR__ . '/includes/parser/Preprocessor_DOM.php',
-	'PPDPart_Hash' => __DIR__ . '/includes/parser/Preprocessor_Hash.php',
-	'PPDStack' => __DIR__ . '/includes/parser/Preprocessor_DOM.php',
-	'PPDStackElement' => __DIR__ . '/includes/parser/Preprocessor_DOM.php',
-	'PPDStackElement_Hash' => __DIR__ . '/includes/parser/Preprocessor_Hash.php',
-	'PPDStack_Hash' => __DIR__ . '/includes/parser/Preprocessor_Hash.php',
-	'PPFrame' => __DIR__ . '/includes/parser/Preprocessor.php',
-	'PPFrame_DOM' => __DIR__ . '/includes/parser/Preprocessor_DOM.php',
-	'PPFrame_Hash' => __DIR__ . '/includes/parser/Preprocessor_Hash.php',
+	'PPCustomFrame_DOM' => __DIR__ . '/includes/parser/PPCustomFrame_DOM.php',
+	'PPCustomFrame_Hash' => __DIR__ . '/includes/parser/PPCustomFrame_Hash.php',
+	'PPDPart' => __DIR__ . '/includes/parser/PPDPart.php',
+	'PPDPart_Hash' => __DIR__ . '/includes/parser/PPDPart_Hash.php',
+	'PPDStack' => __DIR__ . '/includes/parser/PPDStack.php',
+	'PPDStackElement' => __DIR__ . '/includes/parser/PPDStackElement.php',
+	'PPDStackElement_Hash' => __DIR__ . '/includes/parser/PPDStackElement_Hash.php',
+	'PPDStack_Hash' => __DIR__ . '/includes/parser/PPDStack_Hash.php',
+	'PPFrame' => __DIR__ . '/includes/parser/PPFrame.php',
+	'PPFrame_DOM' => __DIR__ . '/includes/parser/PPFrame_DOM.php',
+	'PPFrame_Hash' => __DIR__ . '/includes/parser/PPFrame_Hash.php',
 	'PPFuzzTest' => __DIR__ . '/maintenance/preprocessorFuzzTest.php',
 	'PPFuzzTester' => __DIR__ . '/maintenance/preprocessorFuzzTest.php',
 	'PPFuzzUser' => __DIR__ . '/maintenance/preprocessorFuzzTest.php',
-	'PPNode' => __DIR__ . '/includes/parser/Preprocessor.php',
-	'PPNode_DOM' => __DIR__ . '/includes/parser/Preprocessor_DOM.php',
-	'PPNode_Hash_Array' => __DIR__ . '/includes/parser/Preprocessor_Hash.php',
-	'PPNode_Hash_Attr' => __DIR__ . '/includes/parser/Preprocessor_Hash.php',
-	'PPNode_Hash_Text' => __DIR__ . '/includes/parser/Preprocessor_Hash.php',
-	'PPNode_Hash_Tree' => __DIR__ . '/includes/parser/Preprocessor_Hash.php',
-	'PPTemplateFrame_DOM' => __DIR__ . '/includes/parser/Preprocessor_DOM.php',
-	'PPTemplateFrame_Hash' => __DIR__ . '/includes/parser/Preprocessor_Hash.php',
+	'PPNode' => __DIR__ . '/includes/parser/PPNode.php',
+	'PPNode_DOM' => __DIR__ . '/includes/parser/PPNode_DOM.php',
+	'PPNode_Hash_Array' => __DIR__ . '/includes/parser/PPNode_Hash_Array.php',
+	'PPNode_Hash_Attr' => __DIR__ . '/includes/parser/PPNode_Hash_Attr.php',
+	'PPNode_Hash_Text' => __DIR__ . '/includes/parser/PPNode_Hash_Text.php',
+	'PPNode_Hash_Tree' => __DIR__ . '/includes/parser/PPNode_Hash_Tree.php',
+	'PPTemplateFrame_DOM' => __DIR__ . '/includes/parser/PPTemplateFrame_DOM.php',
+	'PPTemplateFrame_Hash' => __DIR__ . '/includes/parser/PPTemplateFrame_Hash.php',
 	'PackedHoverImageGallery' => __DIR__ . '/includes/gallery/PackedHoverImageGallery.php',
 	'PackedImageGallery' => __DIR__ . '/includes/gallery/PackedImageGallery.php',
 	'PackedOverlayImageGallery' => __DIR__ . '/includes/gallery/PackedOverlayImageGallery.php',
diff --git a/includes/parser/PPCustomFrame_DOM.php b/includes/parser/PPCustomFrame_DOM.php
new file mode 100644
index 0000000000..70663a0dea
--- /dev/null
+++ b/includes/parser/PPCustomFrame_DOM.php
@@ -0,0 +1,70 @@
+<?php
+/**
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ * @ingroup Parser
+ */
+
+/**
+ * Expansion frame with custom arguments
+ * @ingroup Parser
+ */
+// phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
+class PPCustomFrame_DOM extends PPFrame_DOM {
+
+	public $args;
+
+	public function __construct( $preprocessor, $args ) {
+		parent::__construct( $preprocessor );
+		$this->args = $args;
+	}
+
+	public function __toString() {
+		$s = 'cstmframe{';
+		$first = true;
+		foreach ( $this->args as $name => $value ) {
+			if ( $first ) {
+				$first = false;
+			} else {
+				$s .= ', ';
+			}
+			$s .= "\"$name\":\"" .
+				str_replace( '"', '\\"', $value->__toString() ) . '"';
+		}
+		$s .= '}';
+		return $s;
+	}
+
+	/**
+	 * @return bool
+	 */
+	public function isEmpty() {
+		return !count( $this->args );
+	}
+
+	/**
+	 * @param int|string $index
+	 * @return string|bool
+	 */
+	public function getArgument( $index ) {
+		return $this->args[$index] ?? false;
+	}
+
+	public function getArguments() {
+		return $this->args;
+	}
+}
diff --git a/includes/parser/PPCustomFrame_Hash.php b/includes/parser/PPCustomFrame_Hash.php
new file mode 100644
index 0000000000..a92b104d5d
--- /dev/null
+++ b/includes/parser/PPCustomFrame_Hash.php
@@ -0,0 +1,70 @@
+<?php
+/**
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ * @ingroup Parser
+ */
+
+/**
+ * Expansion frame with custom arguments
+ * @ingroup Parser
+ */
+// phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
+class PPCustomFrame_Hash extends PPFrame_Hash {
+
+	public $args;
+
+	public function __construct( $preprocessor, $args ) {
+		parent::__construct( $preprocessor );
+		$this->args = $args;
+	}
+
+	public function __toString() {
+		$s = 'cstmframe{';
+		$first = true;
+		foreach ( $this->args as $name => $value ) {
+			if ( $first ) {
+				$first = false;
+			} else {
+				$s .= ', ';
+			}
+			$s .= "\"$name\":\"" .
+				str_replace( '"', '\\"', $value->__toString() ) . '"';
+		}
+		$s .= '}';
+		return $s;
+	}
+
+	/**
+	 * @return bool
+	 */
+	public function isEmpty() {
+		return !count( $this->args );
+	}
+
+	/**
+	 * @param int|string $index
+	 * @return string|bool
+	 */
+	public function getArgument( $index ) {
+		return $this->args[$index] ?? false;
+	}
+
+	public function getArguments() {
+		return $this->args;
+	}
+}
diff --git a/includes/parser/PPDPart.php b/includes/parser/PPDPart.php
new file mode 100644
index 0000000000..187373052c
--- /dev/null
+++ b/includes/parser/PPDPart.php
@@ -0,0 +1,39 @@
+<?php
+/**
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ * @ingroup Parser
+ */
+
+/**
+ * @ingroup Parser
+ */
+class PPDPart {
+	/**
+	 * @var string Output accumulator string
+	 */
+	public $out;
+
+	// Optional member variables:
+	//   eqpos        Position of equals sign in output accumulator
+	//   commentEnd   Past-the-end input pointer for the last comment encountered
+	//   visualEnd    Past-the-end input pointer for the end of the accumulator minus comments
+
+	public function __construct( $out = '' ) {
+		$this->out = $out;
+	}
+}
diff --git a/includes/parser/PPDPart_Hash.php b/includes/parser/PPDPart_Hash.php
new file mode 100644
index 0000000000..7507f06fe0
--- /dev/null
+++ b/includes/parser/PPDPart_Hash.php
@@ -0,0 +1,36 @@
+<?php
+/**
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ * @ingroup Parser
+ */
+
+/**
+ * @ingroup Parser
+ */
+// phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
+class PPDPart_Hash extends PPDPart {
+
+	public function __construct( $out = '' ) {
+		if ( $out !== '' ) {
+			$accum = [ $out ];
+		} else {
+			$accum = [];
+		}
+		parent::__construct( $accum );
+	}
+}
diff --git a/includes/parser/PPDStack.php b/includes/parser/PPDStack.php
new file mode 100644
index 0000000000..4108bd7e13
--- /dev/null
+++ b/includes/parser/PPDStack.php
@@ -0,0 +1,113 @@
+<?php
+/**
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ * @ingroup Parser
+ */
+
+/**
+ * Stack class to help Preprocessor::preprocessToObj()
+ * @ingroup Parser
+ */
+class PPDStack {
+	public $stack, $rootAccum;
+
+	/**
+	 * @var PPDStack
+	 */
+	public $top;
+	public $out;
+	public $elementClass = PPDStackElement::class;
+
+	public static $false = false;
+
+	public function __construct() {
+		$this->stack = [];
+		$this->top = false;
+		$this->rootAccum = '';
+		$this->accum =& $this->rootAccum;
+	}
+
+	/**
+	 * @return int
+	 */
+	public function count() {
+		return count( $this->stack );
+	}
+
+	public function &getAccum() {
+		return $this->accum;
+	}
+
+	/**
+	 * @return bool|PPDPart
+	 */
+	public function getCurrentPart() {
+		if ( $this->top === false ) {
+			return false;
+		} else {
+			return $this->top->getCurrentPart();
+		}
+	}
+
+	public function push( $data ) {
+		if ( $data instanceof $this->elementClass ) {
+			$this->stack[] = $data;
+		} else {
+			$class = $this->elementClass;
+			$this->stack[] = new $class( $data );
+		}
+		$this->top = $this->stack[count( $this->stack ) - 1];
+		$this->accum =& $this->top->getAccum();
+	}
+
+	public function pop() {
+		if ( $this->stack === [] ) {
+			throw new MWException( __METHOD__ . ': no elements remaining' );
+		}
+		$temp = array_pop( $this->stack );
+
+		if ( count( $this->stack ) ) {
+			$this->top = $this->stack[count( $this->stack ) - 1];
+			$this->accum =& $this->top->getAccum();
+		} else {
+			$this->top = self::$false;
+			$this->accum =& $this->rootAccum;
+		}
+		return $temp;
+	}
+
+	public function addPart( $s = '' ) {
+		$this->top->addPart( $s );
+		$this->accum =& $this->top->getAccum();
+	}
+
+	/**
+	 * @return array
+	 */
+	public function getFlags() {
+		if ( $this->stack === [] ) {
+			return [
+				'findEquals' => false,
+				'findPipe' => false,
+				'inHeading' => false,
+			];
+		} else {
+			return $this->top->getFlags();
+		}
+	}
+}
diff --git a/includes/parser/PPDStackElement.php b/includes/parser/PPDStackElement.php
new file mode 100644
index 0000000000..116244dbb7
--- /dev/null
+++ b/includes/parser/PPDStackElement.php
@@ -0,0 +1,129 @@
+<?php
+/**
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ * @ingroup Parser
+ */
+
+/**
+ * @ingroup Parser
+ */
+class PPDStackElement {
+	/**
+	 * @var string Opening character (\n for heading)
+	 */
+	public $open;
+
+	/**
+	 * @var string Matching closing character
+	 */
+	public $close;
+
+	/**
+	 * @var string Saved prefix that may affect later processing,
+	 *  e.g. to differentiate `-{{{{` and `{{{{` after later seeing `}}}`.
+	 */
+	public $savedPrefix = '';
+
+	/**
+	 * @var int Number of opening characters found (number of "=" for heading)
+	 */
+	public $count;
+
+	/**
+	 * @var PPDPart[] Array of PPDPart objects describing pipe-separated parts.
+	 */
+	public $parts;
+
+	/**
+	 * @var bool True if the open char appeared at the start of the input line.
+	 *  Not set for headings.
+	 */
+	public $lineStart;
+
+	public $partClass = PPDPart::class;
+
+	public function __construct( $data = [] ) {
+		$class = $this->partClass;
+		$this->parts = [ new $class ];
+
+		foreach ( $data as $name => $value ) {
+			$this->$name = $value;
+		}
+	}
+
+	public function &getAccum() {
+		return $this->parts[count( $this->parts ) - 1]->out;
+	}
+
+	public function addPart( $s = '' ) {
+		$class = $this->partClass;
+		$this->parts[] = new $class( $s );
+	}
+
+	/**
+	 * @return PPDPart
+	 */
+	public function getCurrentPart() {
+		return $this->parts[count( $this->parts ) - 1];
+	}
+
+	/**
+	 * @return array
+	 */
+	public function getFlags() {
+		$partCount = count( $this->parts );
+		$findPipe = $this->open != "\n" && $this->open != '[';
+		return [
+			'findPipe' => $findPipe,
+			'findEquals' => $findPipe && $partCount > 1 && !isset( $this->parts[$partCount - 1]->eqpos ),
+			'inHeading' => $this->open == "\n",
+		];
+	}
+
+	/**
+	 * Get the output string that would result if the close is not found.
+	 *
+	 * @param bool|int $openingCount
+	 * @return string
+	 */
+	public function breakSyntax( $openingCount = false ) {
+		if ( $this->open == "\n" ) {
+			$s = $this->savedPrefix . $this->parts[0]->out;
+		} else {
+			if ( $openingCount === false ) {
+				$openingCount = $this->count;
+			}
+			$s = substr( $this->open, 0, -1 );
+			$s .= str_repeat(
+				substr( $this->open, -1 ),
+				$openingCount - strlen( $s )
+			);
+			$s = $this->savedPrefix . $s;
+			$first = true;
+			foreach ( $this->parts as $part ) {
+				if ( $first ) {
+					$first = false;
+				} else {
+					$s .= '|';
+				}
+				$s .= $part->out;
+			}
+		}
+		return $s;
+	}
+}
diff --git a/includes/parser/PPDStackElement_Hash.php b/includes/parser/PPDStackElement_Hash.php
new file mode 100644
index 0000000000..26351b21d3
--- /dev/null
+++ b/includes/parser/PPDStackElement_Hash.php
@@ -0,0 +1,73 @@
+<?php
+/**
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ * @ingroup Parser
+ */
+
+/**
+ * @ingroup Parser
+ */
+// phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
+class PPDStackElement_Hash extends PPDStackElement {
+
+	public function __construct( $data = [] ) {
+		$this->partClass = PPDPart_Hash::class;
+		parent::__construct( $data );
+	}
+
+	/**
+	 * Get the accumulator that would result if the close is not found.
+	 *
+	 * @param int|bool $openingCount
+	 * @return array
+	 */
+	public function breakSyntax( $openingCount = false ) {
+		if ( $this->open == "\n" ) {
+			$accum = array_merge( [ $this->savedPrefix ], $this->parts[0]->out );
+		} else {
+			if ( $openingCount === false ) {
+				$openingCount = $this->count;
+			}
+			$s = substr( $this->open, 0, -1 );
+			$s .= str_repeat(
+				substr( $this->open, -1 ),
+				$openingCount - strlen( $s )
+			);
+			$accum = [ $this->savedPrefix . $s ];
+			$lastIndex = 0;
+			$first = true;
+			foreach ( $this->parts as $part ) {
+				if ( $first ) {
+					$first = false;
+				} elseif ( is_string( $accum[$lastIndex] ) ) {
+					$accum[$lastIndex] .= '|';
+				} else {
+					$accum[++$lastIndex] = '|';
+				}
+				foreach ( $part->out as $node ) {
+					if ( is_string( $node ) && is_string( $accum[$lastIndex] ) ) {
+						$accum[$lastIndex] .= $node;
+					} else {
+						$accum[++$lastIndex] = $node;
+					}
+				}
+			}
+		}
+		return $accum;
+	}
+}
diff --git a/includes/parser/PPDStack_Hash.php b/includes/parser/PPDStack_Hash.php
new file mode 100644
index 0000000000..1e50b1ca18
--- /dev/null
+++ b/includes/parser/PPDStack_Hash.php
@@ -0,0 +1,34 @@
+<?php
+/**
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ * @ingroup Parser
+ */
+
+/**
+ * Stack class to help Preprocessor::preprocessToObj()
+ * @ingroup Parser
+ */
+// phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
+class PPDStack_Hash extends PPDStack {
+
+	public function __construct() {
+		$this->elementClass = PPDStackElement_Hash::class;
+		parent::__construct();
+		$this->rootAccum = [];
+	}
+}
diff --git a/includes/parser/PPFrame.php b/includes/parser/PPFrame.php
new file mode 100644
index 0000000000..79c7c3b30a
--- /dev/null
+++ b/includes/parser/PPFrame.php
@@ -0,0 +1,204 @@
+<?php
+/**
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ * @ingroup Parser
+ */
+
+/**
+ * @ingroup Parser
+ */
+interface PPFrame {
+	const NO_ARGS = 1;
+	const NO_TEMPLATES = 2;
+	const STRIP_COMMENTS = 4;
+	const NO_IGNORE = 8;
+	const RECOVER_COMMENTS = 16;
+	const NO_TAGS = 32;
+
+	const RECOVER_ORIG = self::NO_ARGS | self::NO_TEMPLATES | self::NO_IGNORE |
+		self::RECOVER_COMMENTS | self::NO_TAGS;
+
+	/** This constant exists when $indexOffset is supported in newChild() */
+	const SUPPORTS_INDEX_OFFSET = 1;
+
+	/**
+	 * Create a child frame
+	 *
+	 * @param array|bool $args
+	 * @param bool|Title $title
+	 * @param int $indexOffset A number subtracted from the index attributes of the arguments
+	 *
+	 * @return PPFrame
+	 */
+	public function newChild( $args = false, $title = false, $indexOffset = 0 );
+
+	/**
+	 * Expand a document tree node, caching the result on its parent with the given key
+	 * @param string|int $key
+	 * @param string|PPNode $root
+	 * @param int $flags
+	 * @return string
+	 */
+	public function cachedExpand( $key, $root, $flags = 0 );
+
+	/**
+	 * Expand a document tree node
+	 * @param string|PPNode $root
+	 * @param int $flags
+	 * @return string
+	 */
+	public function expand( $root, $flags = 0 );
+
+	/**
+	 * Implode with flags for expand()
+	 * @param string $sep
+	 * @param int $flags
+	 * @param string|PPNode $args,...
+	 * @return string
+	 */
+	public function implodeWithFlags( $sep, $flags /*, ... */ );
+
+	/**
+	 * Implode with no flags specified
+	 * @param string $sep
+	 * @param string|PPNode $args,...
+	 * @return string
+	 */
+	public function implode( $sep /*, ... */ );
+
+	/**
+	 * Makes an object that, when expand()ed, will be the same as one obtained
+	 * with implode()
+	 * @param string $sep
+	 * @param string|PPNode $args,...
+	 * @return PPNode
+	 */
+	public function virtualImplode( $sep /*, ... */ );
+
+	/**
+	 * Virtual implode with brackets
+	 * @param string $start
+	 * @param string $sep
+	 * @param string $end
+	 * @param string|PPNode $args,...
+	 * @return PPNode
+	 */
+	public function virtualBracketedImplode( $start, $sep, $end /*, ... */ );
+
+	/**
+	 * Returns true if there are no arguments in this frame
+	 *
+	 * @return bool
+	 */
+	public function isEmpty();
+
+	/**
+	 * Returns all arguments of this frame
+	 * @return array
+	 */
+	public function getArguments();
+
+	/**
+	 * Returns all numbered arguments of this frame
+	 * @return array
+	 */
+	public function getNumberedArguments();
+
+	/**
+	 * Returns all named arguments of this frame
+	 * @return array
+	 */
+	public function getNamedArguments();
+
+	/**
+	 * Get an argument to this frame by name
+	 * @param int|string $name
+	 * @return string|bool
+	 */
+	public function getArgument( $name );
+
+	/**
+	 * Returns true if the infinite loop check is OK, false if a loop is detected
+	 *
+	 * @param Title $title
+	 * @return bool
+	 */
+	public function loopCheck( $title );
+
+	/**
+	 * Return true if the frame is a template frame
+	 * @return bool
+	 */
+	public function isTemplate();
+
+	/**
+	 * Set the "volatile" flag.
+	 *
+	 * Note that this is somewhat of a "hack" in order to make extensions
+	 * with side effects (such as Cite) work with the PHP parser. New
+	 * extensions should be written in a way that they do not need this
+	 * function, because other parsers (such as Parsoid) are not guaranteed
+	 * to respect it, and it may be removed in the future.
+	 *
+	 * @param bool $flag
+	 */
+	public function setVolatile( $flag = true );
+
+	/**
+	 * Get the "volatile" flag.
+	 *
+	 * Callers should avoid caching the result of an expansion if it has the
+	 * volatile flag set.
+	 *
+	 * @see self::setVolatile()
+	 * @return bool
+	 */
+	public function isVolatile();
+
+	/**
+	 * Get the TTL of the frame's output.
+	 *
+	 * This is the maximum amount of time, in seconds, that this frame's
+	 * output should be cached for. A value of null indicates that no
+	 * maximum has been specified.
+	 *
+	 * Note that this TTL only applies to caching frames as parts of pages.
+	 * It is not relevant to caching the entire rendered output of a page.
+	 *
+	 * @return int|null
+	 */
+	public function getTTL();
+
+	/**
+	 * Set the TTL of the output of this frame and all of its ancestors.
+	 * Has no effect if the new TTL is greater than the one already set.
+	 * Note that it is the caller's responsibility to change the cache
+	 * expiry of the page as a whole, if such behavior is desired.
+	 *
+	 * @see self::getTTL()
+	 * @param int $ttl
+	 */
+	public function setTTL( $ttl );
+
+	/**
+	 * Get a title of frame
+	 *
+	 * @return Title
+	 */
+	public function getTitle();
+}
diff --git a/includes/parser/PPFrame_DOM.php b/includes/parser/PPFrame_DOM.php
new file mode 100644
index 0000000000..a7fea0028a
--- /dev/null
+++ b/includes/parser/PPFrame_DOM.php
@@ -0,0 +1,631 @@
+<?php
+/**
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ * @ingroup Parser
+ */
+
+/**
+ * An expansion frame, used as a context to expand the result of preprocessToObj()
+ * @ingroup Parser
+ */
+// phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
+class PPFrame_DOM implements PPFrame {
+
+	/**
+	 * @var Preprocessor
+	 */
+	public $preprocessor;
+
+	/**
+	 * @var Parser
+	 */
+	public $parser;
+
+	/**
+	 * @var Title
+	 */
+	public $title;
+	public $titleCache;
+
+	/**
+	 * Hashtable listing templates which are disallowed for expansion in this frame,
+	 * having been encountered previously in parent frames.
+	 */
+	public $loopCheckHash;
+
+	/**
+	 * Recursion depth of this frame, top = 0
+	 * Note that this is NOT the same as expansion depth in expand()
+	 */
+	public $depth;
+
+	private $volatile = false;
+	private $ttl = null;
+
+	/**
+	 * @var array
+	 */
+	protected $childExpansionCache;
+
+	/**
+	 * Construct a new preprocessor frame.
+	 * @param Preprocessor $preprocessor The parent preprocessor
+	 */
+	public function __construct( $preprocessor ) {
+		$this->preprocessor = $preprocessor;
+		$this->parser = $preprocessor->parser;
+		$this->title = $this->parser->mTitle;
+		$this->titleCache = [ $this->title ? $this->title->getPrefixedDBkey() : false ];
+		$this->loopCheckHash = [];
+		$this->depth = 0;
+		$this->childExpansionCache = [];
+	}
+
+	/**
+	 * Create a new child frame
+	 * $args is optionally a multi-root PPNode or array containing the template arguments
+	 *
+	 * @param bool|array $args
+	 * @param Title|bool $title
+	 * @param int $indexOffset
+	 * @return PPTemplateFrame_DOM
+	 */
+	public function newChild( $args = false, $title = false, $indexOffset = 0 ) {
+		$namedArgs = [];
+		$numberedArgs = [];
+		if ( $title === false ) {
+			$title = $this->title;
+		}
+		if ( $args !== false ) {
+			$xpath = false;
+			if ( $args instanceof PPNode ) {
+				$args = $args->node;
+			}
+			foreach ( $args as $arg ) {
+				if ( $arg instanceof PPNode ) {
+					$arg = $arg->node;
+				}
+				if ( !$xpath || $xpath->document !== $arg->ownerDocument ) {
+					$xpath = new DOMXPath( $arg->ownerDocument );
+				}
+
+				$nameNodes = $xpath->query( 'name', $arg );
+				$value = $xpath->query( 'value', $arg );
+				if ( $nameNodes->item( 0 )->hasAttributes() ) {
+					// Numbered parameter
+					$index = $nameNodes->item( 0 )->attributes->getNamedItem( 'index' )->textContent;
+					$index = $index - $indexOffset;
+					if ( isset( $namedArgs[$index] ) || isset( $numberedArgs[$index] ) ) {
+						$this->parser->getOutput()->addWarning( wfMessage( 'duplicate-args-warning',
+							wfEscapeWikiText( $this->title ),
+							wfEscapeWikiText( $title ),
+							wfEscapeWikiText( $index ) )->text() );
+						$this->parser->addTrackingCategory( 'duplicate-args-category' );
+					}
+					$numberedArgs[$index] = $value->item( 0 );
+					unset( $namedArgs[$index] );
+				} else {
+					// Named parameter
+					$name = trim( $this->expand( $nameNodes->item( 0 ), PPFrame::STRIP_COMMENTS ) );
+					if ( isset( $namedArgs[$name] ) || isset( $numberedArgs[$name] ) ) {
+						$this->parser->getOutput()->addWarning( wfMessage( 'duplicate-args-warning',
+							wfEscapeWikiText( $this->title ),
+							wfEscapeWikiText( $title ),
+							wfEscapeWikiText( $name ) )->text() );
+						$this->parser->addTrackingCategory( 'duplicate-args-category' );
+					}
+					$namedArgs[$name] = $value->item( 0 );
+					unset( $numberedArgs[$name] );
+				}
+			}
+		}
+		return new PPTemplateFrame_DOM( $this->preprocessor, $this, $numberedArgs, $namedArgs, $title );
+	}
+
+	/**
+	 * @throws MWException
+	 * @param string|int $key
+	 * @param string|PPNode_DOM|DOMDocument $root
+	 * @param int $flags
+	 * @return string
+	 */
+	public function cachedExpand( $key, $root, $flags = 0 ) {
+		// we don't have a parent, so we don't have a cache
+		return $this->expand( $root, $flags );
+	}
+
+	/**
+	 * @throws MWException
+	 * @param string|PPNode_DOM|DOMDocument $root
+	 * @param int $flags
+	 * @return string
+	 */
+	public function expand( $root, $flags = 0 ) {
+		static $expansionDepth = 0;
+		if ( is_string( $root ) ) {
+			return $root;
+		}
+
+		if ( ++$this->parser->mPPNodeCount > $this->parser->mOptions->getMaxPPNodeCount() ) {
+			$this->parser->limitationWarn( 'node-count-exceeded',
+				$this->parser->mPPNodeCount,
+				$this->parser->mOptions->getMaxPPNodeCount()
+			);
+			return '<span class="error">Node-count limit exceeded</span>';
+		}
+
+		if ( $expansionDepth > $this->parser->mOptions->getMaxPPExpandDepth() ) {
+			$this->parser->limitationWarn( 'expansion-depth-exceeded',
+				$expansionDepth,
+				$this->parser->mOptions->getMaxPPExpandDepth()
+			);
+			return '<span class="error">Expansion depth limit exceeded</span>';
+		}
+		++$expansionDepth;
+		if ( $expansionDepth > $this->parser->mHighestExpansionDepth ) {
+			$this->parser->mHighestExpansionDepth = $expansionDepth;
+		}
+
+		if ( $root instanceof PPNode_DOM ) {
+			$root = $root->node;
+		}
+		if ( $root instanceof DOMDocument ) {
+			$root = $root->documentElement;
+		}
+
+		$outStack = [ '', '' ];
+		$iteratorStack = [ false, $root ];
+		$indexStack = [ 0, 0 ];
+
+		while ( count( $iteratorStack ) > 1 ) {
+			$level = count( $outStack ) - 1;
+			$iteratorNode =& $iteratorStack[$level];
+			$out =& $outStack[$level];
+			$index =& $indexStack[$level];
+
+			if ( $iteratorNode instanceof PPNode_DOM ) {
+				$iteratorNode = $iteratorNode->node;
+			}
+
+			if ( is_array( $iteratorNode ) ) {
+				if ( $index >= count( $iteratorNode ) ) {
+					// All done with this iterator
+					$iteratorStack[$level] = false;
+					$contextNode = false;
+				} else {
+					$contextNode = $iteratorNode[$index];
+					$index++;
+				}
+			} elseif ( $iteratorNode instanceof DOMNodeList ) {
+				if ( $index >= $iteratorNode->length ) {
+					// All done with this iterator
+					$iteratorStack[$level] = false;
+					$contextNode = false;
+				} else {
+					$contextNode = $iteratorNode->item( $index );
+					$index++;
+				}
+			} else {
+				// Copy to $contextNode and then delete from iterator stack,
+				// because this is not an iterator but we do have to execute it once
+				$contextNode = $iteratorStack[$level];
+				$iteratorStack[$level] = false;
+			}
+
+			if ( $contextNode instanceof PPNode_DOM ) {
+				$contextNode = $contextNode->node;
+			}
+
+			$newIterator = false;
+
+			if ( $contextNode === false ) {
+				// nothing to do
+			} elseif ( is_string( $contextNode ) ) {
+				$out .= $contextNode;
+			} elseif ( is_array( $contextNode ) || $contextNode instanceof DOMNodeList ) {
+				$newIterator = $contextNode;
+			} elseif ( $contextNode instanceof DOMNode ) {
+				if ( $contextNode->nodeType == XML_TEXT_NODE ) {
+					$out .= $contextNode->nodeValue;
+				} elseif ( $contextNode->nodeName == 'template' ) {
+					# Double-brace expansion
+					$xpath = new DOMXPath( $contextNode->ownerDocument );
+					$titles = $xpath->query( 'title', $contextNode );
+					$title = $titles->item( 0 );
+					$parts = $xpath->query( 'part', $contextNode );
+					if ( $flags & PPFrame::NO_TEMPLATES ) {
+						$newIterator = $this->virtualBracketedImplode( '{{', '|', '}}', $title, $parts );
+					} else {
+						$lineStart = $contextNode->getAttribute( 'lineStart' );
+						$params = [
+							'title' => new PPNode_DOM( $title ),
+							'parts' => new PPNode_DOM( $parts ),
+							'lineStart' => $lineStart ];
+						$ret = $this->parser->braceSubstitution( $params, $this );
+						if ( isset( $ret['object'] ) ) {
+							$newIterator = $ret['object'];
+						} else {
+							$out .= $ret['text'];
+						}
+					}
+				} elseif ( $contextNode->nodeName == 'tplarg' ) {
+					# Triple-brace expansion
+					$xpath = new DOMXPath( $contextNode->ownerDocument );
+					$titles = $xpath->query( 'title', $contextNode );
+					$title = $titles->item( 0 );
+					$parts = $xpath->query( 'part', $contextNode );
+					if ( $flags & PPFrame::NO_ARGS ) {
+						$newIterator = $this->virtualBracketedImplode( '{{{', '|', '}}}', $title, $parts );
+					} else {
+						$params = [
+							'title' => new PPNode_DOM( $title ),
+							'parts' => new PPNode_DOM( $parts ) ];
+						$ret = $this->parser->argSubstitution( $params, $this );
+						if ( isset( $ret['object'] ) ) {
+							$newIterator = $ret['object'];
+						} else {
+							$out .= $ret['text'];
+						}
+					}
+				} elseif ( $contextNode->nodeName == 'comment' ) {
+					# HTML-style comment
+					# Remove it in HTML, pre+remove and STRIP_COMMENTS modes
+					# Not in RECOVER_COMMENTS mode (msgnw) though.
+					if ( ( $this->parser->ot['html']
+						|| ( $this->parser->ot['pre'] && $this->parser->mOptions->getRemoveComments() )
+						|| ( $flags & PPFrame::STRIP_COMMENTS )
+						) && !( $flags & PPFrame::RECOVER_COMMENTS )
+					) {
+						$out .= '';
+					} elseif ( $this->parser->ot['wiki'] && !( $flags & PPFrame::RECOVER_COMMENTS ) ) {
+						# Add a strip marker in PST mode so that pstPass2() can
+						# run some old-fashioned regexes on the result.
+						# Not in RECOVER_COMMENTS mode (extractSections) though.
+						$out .= $this->parser->insertStripItem( $contextNode->textContent );
+					} else {
+						# Recover the literal comment in RECOVER_COMMENTS and pre+no-remove
+						$out .= $contextNode->textContent;
+					}
+				} elseif ( $contextNode->nodeName == 'ignore' ) {
+					# Output suppression used by <includeonly> etc.
+					# OT_WIKI will only respect <ignore> in substed templates.
+					# The other output types respect it unless NO_IGNORE is set.
+					# extractSections() sets NO_IGNORE and so never respects it.
+					if ( ( !isset( $this->parent ) && $this->parser->ot['wiki'] )
+						|| ( $flags & PPFrame::NO_IGNORE )
+					) {
+						$out .= $contextNode->textContent;
+					} else {
+						$out .= '';
+					}
+				} elseif ( $contextNode->nodeName == 'ext' ) {
+					# Extension tag
+					$xpath = new DOMXPath( $contextNode->ownerDocument );
+					$names = $xpath->query( 'name', $contextNode );
+					$attrs = $xpath->query( 'attr', $contextNode );
+					$inners = $xpath->query( 'inner', $contextNode );
+					$closes = $xpath->query( 'close', $contextNode );
+					if ( $flags & PPFrame::NO_TAGS ) {
+						$s = '<' . $this->expand( $names->item( 0 ), $flags );
+						if ( $attrs->length > 0 ) {
+							$s .= $this->expand( $attrs->item( 0 ), $flags );
+						}
+						if ( $inners->length > 0 ) {
+							$s .= '>' . $this->expand( $inners->item( 0 ), $flags );
+							if ( $closes->length > 0 ) {
+								$s .= $this->expand( $closes->item( 0 ), $flags );
+							}
+						} else {
+							$s .= '/>';
+						}
+						$out .= $s;
+					} else {
+						$params = [
+							'name' => new PPNode_DOM( $names->item( 0 ) ),
+							'attr' => $attrs->length > 0 ? new PPNode_DOM( $attrs->item( 0 ) ) : null,
+							'inner' => $inners->length > 0 ? new PPNode_DOM( $inners->item( 0 ) ) : null,
+							'close' => $closes->length > 0 ? new PPNode_DOM( $closes->item( 0 ) ) : null,
+						];
+						$out .= $this->parser->extensionSubstitution( $params, $this );
+					}
+				} elseif ( $contextNode->nodeName == 'h' ) {
+					# Heading
+					$s = $this->expand( $contextNode->childNodes, $flags );
+
+					# Insert a heading marker only for <h> children of <root>
+					# This is to stop extractSections from going over multiple tree levels
+					if ( $contextNode->parentNode->nodeName == 'root' && $this->parser->ot['html'] ) {
+						# Insert heading index marker
+						$headingIndex = $contextNode->getAttribute( 'i' );
+						$titleText = $this->title->getPrefixedDBkey();
+						$this->parser->mHeadings[] = [ $titleText, $headingIndex ];
+						$serial = count( $this->parser->mHeadings ) - 1;
+						$marker = Parser::MARKER_PREFIX . "-h-$serial-" . Parser::MARKER_SUFFIX;
+						$count = $contextNode->getAttribute( 'level' );
+						$s = substr( $s, 0, $count ) . $marker . substr( $s, $count );
+						$this->parser->mStripState->addGeneral( $marker, '' );
+					}
+					$out .= $s;
+				} else {
+					# Generic recursive expansion
+					$newIterator = $contextNode->childNodes;
+				}
+			} else {
+				throw new MWException( __METHOD__ . ': Invalid parameter type' );
+			}
+
+			if ( $newIterator !== false ) {
+				if ( $newIterator instanceof PPNode_DOM ) {
+					$newIterator = $newIterator->node;
+				}
+				$outStack[] = '';
+				$iteratorStack[] = $newIterator;
+				$indexStack[] = 0;
+			} elseif ( $iteratorStack[$level] === false ) {
+				// Return accumulated value to parent
+				// With tail recursion
+				while ( $iteratorStack[$level] === false && $level > 0 ) {
+					$outStack[$level - 1] .= $out;
+					array_pop( $outStack );
+					array_pop( $iteratorStack );
+					array_pop( $indexStack );
+					$level--;
+				}
+			}
+		}
+		--$expansionDepth;
+		return $outStack[0];
+	}
+
+	/**
+	 * @param string $sep
+	 * @param int $flags
+	 * @param string|PPNode_DOM|DOMDocument ...$args
+	 * @return string
+	 */
+	public function implodeWithFlags( $sep, $flags, ...$args ) {
+		$first = true;
+		$s = '';
+		foreach ( $args as $root ) {
+			if ( $root instanceof PPNode_DOM ) {
+				$root = $root->node;
+			}
+			if ( !is_array( $root ) && !( $root instanceof DOMNodeList ) ) {
+				$root = [ $root ];
+			}
+			foreach ( $root as $node ) {
+				if ( $first ) {
+					$first = false;
+				} else {
+					$s .= $sep;
+				}
+				$s .= $this->expand( $node, $flags );
+			}
+		}
+		return $s;
+	}
+
+	/**
+	 * Implode with no flags specified
+	 * This previously called implodeWithFlags but has now been inlined to reduce stack depth
+	 *
+	 * @param string $sep
+	 * @param string|PPNode_DOM|DOMDocument ...$args
+	 * @return string
+	 */
+	public function implode( $sep, ...$args ) {
+		$first = true;
+		$s = '';
+		foreach ( $args as $root ) {
+			if ( $root instanceof PPNode_DOM ) {
+				$root = $root->node;
+			}
+			if ( !is_array( $root ) && !( $root instanceof DOMNodeList ) ) {
+				$root = [ $root ];
+			}
+			foreach ( $root as $node ) {
+				if ( $first ) {
+					$first = false;
+				} else {
+					$s .= $sep;
+				}
+				$s .= $this->expand( $node );
+			}
+		}
+		return $s;
+	}
+
+	/**
+	 * Makes an object that, when expand()ed, will be the same as one obtained
+	 * with implode()
+	 *
+	 * @param string $sep
+	 * @param string|PPNode_DOM|DOMDocument ...$args
+	 * @return array
+	 */
+	public function virtualImplode( $sep, ...$args ) {
+		$out = [];
+		$first = true;
+
+		foreach ( $args as $root ) {
+			if ( $root instanceof PPNode_DOM ) {
+				$root = $root->node;
+			}
+			if ( !is_array( $root ) && !( $root instanceof DOMNodeList ) ) {
+				$root = [ $root ];
+			}
+			foreach ( $root as $node ) {
+				if ( $first ) {
+					$first = false;
+				} else {
+					$out[] = $sep;
+				}
+				$out[] = $node;
+			}
+		}
+		return $out;
+	}
+
+	/**
+	 * Virtual implode with brackets
+	 * @param string $start
+	 * @param string $sep
+	 * @param string $end
+	 * @param string|PPNode_DOM|DOMDocument ...$args
+	 * @return array
+	 */
+	public function virtualBracketedImplode( $start, $sep, $end, ...$args ) {
+		$out = [ $start ];
+		$first = true;
+
+		foreach ( $args as $root ) {
+			if ( $root instanceof PPNode_DOM ) {
+				$root = $root->node;
+			}
+			if ( !is_array( $root ) && !( $root instanceof DOMNodeList ) ) {
+				$root = [ $root ];
+			}
+			foreach ( $root as $node ) {
+				if ( $first ) {
+					$first = false;
+				} else {
+					$out[] = $sep;
+				}
+				$out[] = $node;
+			}
+		}
+		$out[] = $end;
+		return $out;
+	}
+
+	public function __toString() {
+		return 'frame{}';
+	}
+
+	public function getPDBK( $level = false ) {
+		if ( $level === false ) {
+			return $this->title->getPrefixedDBkey();
+		} else {
+			return $this->titleCache[$level] ?? false;
+		}
+	}
+
+	/**
+	 * @return array
+	 */
+	public function getArguments() {
+		return [];
+	}
+
+	/**
+	 * @return array
+	 */
+	public function getNumberedArguments() {
+		return [];
+	}
+
+	/**
+	 * @return array
+	 */
+	public function getNamedArguments() {
+		return [];
+	}
+
+	/**
+	 * Returns true if there are no arguments in this frame
+	 *
+	 * @return bool
+	 */
+	public function isEmpty() {
+		return true;
+	}
+
+	/**
+	 * @param int|string $name
+	 * @return bool Always false in this implementation.
+	 */
+	public function getArgument( $name ) {
+		return false;
+	}
+
+	/**
+	 * Returns true if the infinite loop check is OK, false if a loop is detected
+	 *
+	 * @param Title $title
+	 * @return bool
+	 */
+	public function loopCheck( $title ) {
+		return !isset( $this->loopCheckHash[$title->getPrefixedDBkey()] );
+	}
+
+	/**
+	 * Return true if the frame is a template frame
+	 *
+	 * @return bool
+	 */
+	public function isTemplate() {
+		return false;
+	}
+
+	/**
+	 * Get a title of frame
+	 *
+	 * @return Title
+	 */
+	public function getTitle() {
+		return $this->title;
+	}
+
+	/**
+	 * Set the volatile flag
+	 *
+	 * @param bool $flag
+	 */
+	public function setVolatile( $flag = true ) {
+		$this->volatile = $flag;
+	}
+
+	/**
+	 * Get the volatile flag
+	 *
+	 * @return bool
+	 */
+	public function isVolatile() {
+		return $this->volatile;
+	}
+
+	/**
+	 * Set the TTL
+	 *
+	 * @param int $ttl
+	 */
+	public function setTTL( $ttl ) {
+		if ( $ttl !== null && ( $this->ttl === null || $ttl < $this->ttl ) ) {
+			$this->ttl = $ttl;
+		}
+	}
+
+	/**
+	 * Get the TTL
+	 *
+	 * @return int|null
+	 */
+	public function getTTL() {
+		return $this->ttl;
+	}
+}
diff --git a/includes/parser/PPFrame_Hash.php b/includes/parser/PPFrame_Hash.php
new file mode 100644
index 0000000000..845ec73c7e
--- /dev/null
+++ b/includes/parser/PPFrame_Hash.php
@@ -0,0 +1,613 @@
+<?php
+/**
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ * @ingroup Parser
+ */
+
+/**
+ * An expansion frame, used as a context to expand the result of preprocessToObj()
+ * @ingroup Parser
+ */
+// phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
+class PPFrame_Hash implements PPFrame {
+
+	/**
+	 * @var Parser
+	 */
+	public $parser;
+
+	/**
+	 * @var Preprocessor
+	 */
+	public $preprocessor;
+
+	/**
+	 * @var Title
+	 */
+	public $title;
+	public $titleCache;
+
+	/**
+	 * Hashtable listing templates which are disallowed for expansion in this frame,
+	 * having been encountered previously in parent frames.
+	 */
+	public $loopCheckHash;
+
+	/**
+	 * Recursion depth of this frame, top = 0
+	 * Note that this is NOT the same as expansion depth in expand()
+	 */
+	public $depth;
+
+	private $volatile = false;
+	private $ttl = null;
+
+	/**
+	 * @var array
+	 */
+	protected $childExpansionCache;
+
+	/**
+	 * Construct a new preprocessor frame.
+	 * @param Preprocessor $preprocessor The parent preprocessor
+	 */
+	public function __construct( $preprocessor ) {
+		$this->preprocessor = $preprocessor;
+		$this->parser = $preprocessor->parser;
+		$this->title = $this->parser->mTitle;
+		$this->titleCache = [ $this->title ? $this->title->getPrefixedDBkey() : false ];
+		$this->loopCheckHash = [];
+		$this->depth = 0;
+		$this->childExpansionCache = [];
+	}
+
+	/**
+	 * Create a new child frame
+	 * $args is optionally a multi-root PPNode or array containing the template arguments
+	 *
+	 * @param array|bool|PPNode_Hash_Array $args
+	 * @param Title|bool $title
+	 * @param int $indexOffset
+	 * @throws MWException
+	 * @return PPTemplateFrame_Hash
+	 */
+	public function newChild( $args = false, $title = false, $indexOffset = 0 ) {
+		$namedArgs = [];
+		$numberedArgs = [];
+		if ( $title === false ) {
+			$title = $this->title;
+		}
+		if ( $args !== false ) {
+			if ( $args instanceof PPNode_Hash_Array ) {
+				$args = $args->value;
+			} elseif ( !is_array( $args ) ) {
+				throw new MWException( __METHOD__ . ': $args must be array or PPNode_Hash_Array' );
+			}
+			foreach ( $args as $arg ) {
+				$bits = $arg->splitArg();
+				if ( $bits['index'] !== '' ) {
+					// Numbered parameter
+					$index = $bits['index'] - $indexOffset;
+					if ( isset( $namedArgs[$index] ) || isset( $numberedArgs[$index] ) ) {
+						$this->parser->getOutput()->addWarning( wfMessage( 'duplicate-args-warning',
+							wfEscapeWikiText( $this->title ),
+							wfEscapeWikiText( $title ),
+							wfEscapeWikiText( $index ) )->text() );
+						$this->parser->addTrackingCategory( 'duplicate-args-category' );
+					}
+					$numberedArgs[$index] = $bits['value'];
+					unset( $namedArgs[$index] );
+				} else {
+					// Named parameter
+					$name = trim( $this->expand( $bits['name'], PPFrame::STRIP_COMMENTS ) );
+					if ( isset( $namedArgs[$name] ) || isset( $numberedArgs[$name] ) ) {
+						$this->parser->getOutput()->addWarning( wfMessage( 'duplicate-args-warning',
+							wfEscapeWikiText( $this->title ),
+							wfEscapeWikiText( $title ),
+							wfEscapeWikiText( $name ) )->text() );
+						$this->parser->addTrackingCategory( 'duplicate-args-category' );
+					}
+					$namedArgs[$name] = $bits['value'];
+					unset( $numberedArgs[$name] );
+				}
+			}
+		}
+		return new PPTemplateFrame_Hash( $this->preprocessor, $this, $numberedArgs, $namedArgs, $title );
+	}
+
+	/**
+	 * @throws MWException
+	 * @param string|int $key
+	 * @param string|PPNode $root
+	 * @param int $flags
+	 * @return string
+	 */
+	public function cachedExpand( $key, $root, $flags = 0 ) {
+		// we don't have a parent, so we don't have a cache
+		return $this->expand( $root, $flags );
+	}
+
+	/**
+	 * @throws MWException
+	 * @param string|PPNode $root
+	 * @param int $flags
+	 * @return string
+	 */
+	public function expand( $root, $flags = 0 ) {
+		static $expansionDepth = 0;
+		if ( is_string( $root ) ) {
+			return $root;
+		}
+
+		if ( ++$this->parser->mPPNodeCount > $this->parser->mOptions->getMaxPPNodeCount() ) {
+			$this->parser->limitationWarn( 'node-count-exceeded',
+					$this->parser->mPPNodeCount,
+					$this->parser->mOptions->getMaxPPNodeCount()
+			);
+			return '<span class="error">Node-count limit exceeded</span>';
+		}
+		if ( $expansionDepth > $this->parser->mOptions->getMaxPPExpandDepth() ) {
+			$this->parser->limitationWarn( 'expansion-depth-exceeded',
+					$expansionDepth,
+					$this->parser->mOptions->getMaxPPExpandDepth()
+			);
+			return '<span class="error">Expansion depth limit exceeded</span>';
+		}
+		++$expansionDepth;
+		if ( $expansionDepth > $this->parser->mHighestExpansionDepth ) {
+			$this->parser->mHighestExpansionDepth = $expansionDepth;
+		}
+
+		$outStack = [ '', '' ];
+		$iteratorStack = [ false, $root ];
+		$indexStack = [ 0, 0 ];
+
+		while ( count( $iteratorStack ) > 1 ) {
+			$level = count( $outStack ) - 1;
+			$iteratorNode =& $iteratorStack[$level];
+			$out =& $outStack[$level];
+			$index =& $indexStack[$level];
+
+			if ( is_array( $iteratorNode ) ) {
+				if ( $index >= count( $iteratorNode ) ) {
+					// All done with this iterator
+					$iteratorStack[$level] = false;
+					$contextNode = false;
+				} else {
+					$contextNode = $iteratorNode[$index];
+					$index++;
+				}
+			} elseif ( $iteratorNode instanceof PPNode_Hash_Array ) {
+				if ( $index >= $iteratorNode->getLength() ) {
+					// All done with this iterator
+					$iteratorStack[$level] = false;
+					$contextNode = false;
+				} else {
+					$contextNode = $iteratorNode->item( $index );
+					$index++;
+				}
+			} else {
+				// Copy to $contextNode and then delete from iterator stack,
+				// because this is not an iterator but we do have to execute it once
+				$contextNode = $iteratorStack[$level];
+				$iteratorStack[$level] = false;
+			}
+
+			$newIterator = false;
+			$contextName = false;
+			$contextChildren = false;
+
+			if ( $contextNode === false ) {
+				// nothing to do
+			} elseif ( is_string( $contextNode ) ) {
+				$out .= $contextNode;
+			} elseif ( $contextNode instanceof PPNode_Hash_Array ) {
+				$newIterator = $contextNode;
+			} elseif ( $contextNode instanceof PPNode_Hash_Attr ) {
+				// No output
+			} elseif ( $contextNode instanceof PPNode_Hash_Text ) {
+				$out .= $contextNode->value;
+			} elseif ( $contextNode instanceof PPNode_Hash_Tree ) {
+				$contextName = $contextNode->name;
+				$contextChildren = $contextNode->getRawChildren();
+			} elseif ( is_array( $contextNode ) ) {
+				// Node descriptor array
+				if ( count( $contextNode ) !== 2 ) {
+					throw new MWException( __METHOD__ .
+						': found an array where a node descriptor should be' );
+				}
+				list( $contextName, $contextChildren ) = $contextNode;
+			} else {
+				throw new MWException( __METHOD__ . ': Invalid parameter type' );
+			}
+
+			// Handle node descriptor array or tree object
+			if ( $contextName === false ) {
+				// Not a node, already handled above
+			} elseif ( $contextName[0] === '@' ) {
+				// Attribute: no output
+			} elseif ( $contextName === 'template' ) {
+				# Double-brace expansion
+				$bits = PPNode_Hash_Tree::splitRawTemplate( $contextChildren );
+				if ( $flags & PPFrame::NO_TEMPLATES ) {
+					$newIterator = $this->virtualBracketedImplode(
+						'{{', '|', '}}',
+						$bits['title'],
+						$bits['parts']
+					);
+				} else {
+					$ret = $this->parser->braceSubstitution( $bits, $this );
+					if ( isset( $ret['object'] ) ) {
+						$newIterator = $ret['object'];
+					} else {
+						$out .= $ret['text'];
+					}
+				}
+			} elseif ( $contextName === 'tplarg' ) {
+				# Triple-brace expansion
+				$bits = PPNode_Hash_Tree::splitRawTemplate( $contextChildren );
+				if ( $flags & PPFrame::NO_ARGS ) {
+					$newIterator = $this->virtualBracketedImplode(
+						'{{{', '|', '}}}',
+						$bits['title'],
+						$bits['parts']
+					);
+				} else {
+					$ret = $this->parser->argSubstitution( $bits, $this );
+					if ( isset( $ret['object'] ) ) {
+						$newIterator = $ret['object'];
+					} else {
+						$out .= $ret['text'];
+					}
+				}
+			} elseif ( $contextName === 'comment' ) {
+				# HTML-style comment
+				# Remove it in HTML, pre+remove and STRIP_COMMENTS modes
+				# Not in RECOVER_COMMENTS mode (msgnw) though.
+				if ( ( $this->parser->ot['html']
+					|| ( $this->parser->ot['pre'] && $this->parser->mOptions->getRemoveComments() )
+					|| ( $flags & PPFrame::STRIP_COMMENTS )
+					) && !( $flags & PPFrame::RECOVER_COMMENTS )
+				) {
+					$out .= '';
+				} elseif ( $this->parser->ot['wiki'] && !( $flags & PPFrame::RECOVER_COMMENTS ) ) {
+					# Add a strip marker in PST mode so that pstPass2() can
+					# run some old-fashioned regexes on the result.
+					# Not in RECOVER_COMMENTS mode (extractSections) though.
+					$out .= $this->parser->insertStripItem( $contextChildren[0] );
+				} else {
+					# Recover the literal comment in RECOVER_COMMENTS and pre+no-remove
+					$out .= $contextChildren[0];
+				}
+			} elseif ( $contextName === 'ignore' ) {
+				# Output suppression used by <includeonly> etc.
+				# OT_WIKI will only respect <ignore> in substed templates.
+				# The other output types respect it unless NO_IGNORE is set.
+				# extractSections() sets NO_IGNORE and so never respects it.
+				if ( ( !isset( $this->parent ) && $this->parser->ot['wiki'] )
+					|| ( $flags & PPFrame::NO_IGNORE )
+				) {
+					$out .= $contextChildren[0];
+				} else {
+					// $out .= '';
+				}
+			} elseif ( $contextName === 'ext' ) {
+				# Extension tag
+				$bits = PPNode_Hash_Tree::splitRawExt( $contextChildren ) +
+					[ 'attr' => null, 'inner' => null, 'close' => null ];
+				if ( $flags & PPFrame::NO_TAGS ) {
+					$s = '<' . $bits['name']->getFirstChild()->value;
+					if ( $bits['attr'] ) {
+						$s .= $bits['attr']->getFirstChild()->value;
+					}
+					if ( $bits['inner'] ) {
+						$s .= '>' . $bits['inner']->getFirstChild()->value;
+						if ( $bits['close'] ) {
+							$s .= $bits['close']->getFirstChild()->value;
+						}
+					} else {
+						$s .= '/>';
+					}
+					$out .= $s;
+				} else {
+					$out .= $this->parser->extensionSubstitution( $bits, $this );
+				}
+			} elseif ( $contextName === 'h' ) {
+				# Heading
+				if ( $this->parser->ot['html'] ) {
+					# Expand immediately and insert heading index marker
+					$s = $this->expand( $contextChildren, $flags );
+					$bits = PPNode_Hash_Tree::splitRawHeading( $contextChildren );
+					$titleText = $this->title->getPrefixedDBkey();
+					$this->parser->mHeadings[] = [ $titleText, $bits['i'] ];
+					$serial = count( $this->parser->mHeadings ) - 1;
+					$marker = Parser::MARKER_PREFIX . "-h-$serial-" . Parser::MARKER_SUFFIX;
+					$s = substr( $s, 0, $bits['level'] ) . $marker . substr( $s, $bits['level'] );
+					$this->parser->mStripState->addGeneral( $marker, '' );
+					$out .= $s;
+				} else {
+					# Expand in virtual stack
+					$newIterator = $contextChildren;
+				}
+			} else {
+				# Generic recursive expansion
+				$newIterator = $contextChildren;
+			}
+
+			if ( $newIterator !== false ) {
+				$outStack[] = '';
+				$iteratorStack[] = $newIterator;
+				$indexStack[] = 0;
+			} elseif ( $iteratorStack[$level] === false ) {
+				// Return accumulated value to parent
+				// With tail recursion
+				while ( $iteratorStack[$level] === false && $level > 0 ) {
+					$outStack[$level - 1] .= $out;
+					array_pop( $outStack );
+					array_pop( $iteratorStack );
+					array_pop( $indexStack );
+					$level--;
+				}
+			}
+		}
+		--$expansionDepth;
+		return $outStack[0];
+	}
+
+	/**
+	 * @param string $sep
+	 * @param int $flags
+	 * @param string|PPNode ...$args
+	 * @return string
+	 */
+	public function implodeWithFlags( $sep, $flags, ...$args ) {
+		$first = true;
+		$s = '';
+		foreach ( $args as $root ) {
+			if ( $root instanceof PPNode_Hash_Array ) {
+				$root = $root->value;
+			}
+			if ( !is_array( $root ) ) {
+				$root = [ $root ];
+			}
+			foreach ( $root as $node ) {
+				if ( $first ) {
+					$first = false;
+				} else {
+					$s .= $sep;
+				}
+				$s .= $this->expand( $node, $flags );
+			}
+		}
+		return $s;
+	}
+
+	/**
+	 * Implode with no flags specified
+	 * This previously called implodeWithFlags but has now been inlined to reduce stack depth
+	 * @param string $sep
+	 * @param string|PPNode ...$args
+	 * @return string
+	 */
+	public function implode( $sep, ...$args ) {
+		$first = true;
+		$s = '';
+		foreach ( $args as $root ) {
+			if ( $root instanceof PPNode_Hash_Array ) {
+				$root = $root->value;
+			}
+			if ( !is_array( $root ) ) {
+				$root = [ $root ];
+			}
+			foreach ( $root as $node ) {
+				if ( $first ) {
+					$first = false;
+				} else {
+					$s .= $sep;
+				}
+				$s .= $this->expand( $node );
+			}
+		}
+		return $s;
+	}
+
+	/**
+	 * Makes an object that, when expand()ed, will be the same as one obtained
+	 * with implode()
+	 *
+	 * @param string $sep
+	 * @param string|PPNode ...$args
+	 * @return PPNode_Hash_Array
+	 */
+	public function virtualImplode( $sep, ...$args ) {
+		$out = [];
+		$first = true;
+
+		foreach ( $args as $root ) {
+			if ( $root instanceof PPNode_Hash_Array ) {
+				$root = $root->value;
+			}
+			if ( !is_array( $root ) ) {
+				$root = [ $root ];
+			}
+			foreach ( $root as $node ) {
+				if ( $first ) {
+					$first = false;
+				} else {
+					$out[] = $sep;
+				}
+				$out[] = $node;
+			}
+		}
+		return new PPNode_Hash_Array( $out );
+	}
+
+	/**
+	 * Virtual implode with brackets
+	 *
+	 * @param string $start
+	 * @param string $sep
+	 * @param string $end
+	 * @param string|PPNode ...$args
+	 * @return PPNode_Hash_Array
+	 */
+	public function virtualBracketedImplode( $start, $sep, $end, ...$args ) {
+		$out = [ $start ];
+		$first = true;
+
+		foreach ( $args as $root ) {
+			if ( $root instanceof PPNode_Hash_Array ) {
+				$root = $root->value;
+			}
+			if ( !is_array( $root ) ) {
+				$root = [ $root ];
+			}
+			foreach ( $root as $node ) {
+				if ( $first ) {
+					$first = false;
+				} else {
+					$out[] = $sep;
+				}
+				$out[] = $node;
+			}
+		}
+		$out[] = $end;
+		return new PPNode_Hash_Array( $out );
+	}
+
+	public function __toString() {
+		return 'frame{}';
+	}
+
+	/**
+	 * @param bool $level
+	 * @return array|bool|string
+	 */
+	public function getPDBK( $level = false ) {
+		if ( $level === false ) {
+			return $this->title->getPrefixedDBkey();
+		} else {
+			return $this->titleCache[$level] ?? false;
+		}
+	}
+
+	/**
+	 * @return array
+	 */
+	public function getArguments() {
+		return [];
+	}
+
+	/**
+	 * @return array
+	 */
+	public function getNumberedArguments() {
+		return [];
+	}
+
+	/**
+	 * @return array
+	 */
+	public function getNamedArguments() {
+		return [];
+	}
+
+	/**
+	 * Returns true if there are no arguments in this frame
+	 *
+	 * @return bool
+	 */
+	public function isEmpty() {
+		return true;
+	}
+
+	/**
+	 * @param int|string $name
+	 * @return bool Always false in this implementation.
+	 */
+	public function getArgument( $name ) {
+		return false;
+	}
+
+	/**
+	 * Returns true if the infinite loop check is OK, false if a loop is detected
+	 *
+	 * @param Title $title
+	 *
+	 * @return bool
+	 */
+	public function loopCheck( $title ) {
+		return !isset( $this->loopCheckHash[$title->getPrefixedDBkey()] );
+	}
+
+	/**
+	 * Return true if the frame is a template frame
+	 *
+	 * @return bool
+	 */
+	public function isTemplate() {
+		return false;
+	}
+
+	/**
+	 * Get a title of frame
+	 *
+	 * @return Title
+	 */
+	public function getTitle() {
+		return $this->title;
+	}
+
+	/**
+	 * Set the volatile flag
+	 *
+	 * @param bool $flag
+	 */
+	public function setVolatile( $flag = true ) {
+		$this->volatile = $flag;
+	}
+
+	/**
+	 * Get the volatile flag
+	 *
+	 * @return bool
+	 */
+	public function isVolatile() {
+		return $this->volatile;
+	}
+
+	/**
+	 * Set the TTL
+	 *
+	 * @param int $ttl
+	 */
+	public function setTTL( $ttl ) {
+		if ( $ttl !== null && ( $this->ttl === null || $ttl < $this->ttl ) ) {
+			$this->ttl = $ttl;
+		}
+	}
+
+	/**
+	 * Get the TTL
+	 *
+	 * @return int|null
+	 */
+	public function getTTL() {
+		return $this->ttl;
+	}
+}
diff --git a/includes/parser/PPNode.php b/includes/parser/PPNode.php
new file mode 100644
index 0000000000..2b6cf7c341
--- /dev/null
+++ b/includes/parser/PPNode.php
@@ -0,0 +1,112 @@
+<?php
+/**
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ * @ingroup Parser
+ */
+
+/**
+ * There are three types of nodes:
+ *     * Tree nodes, which have a name and contain other nodes as children
+ *     * Array nodes, which also contain other nodes but aren't considered part of a tree
+ *     * Leaf nodes, which contain the actual data
+ *
+ * This interface provides access to the tree structure and to the contents of array nodes,
+ * but it does not provide access to the internal structure of leaf nodes. Access to leaf
+ * data is provided via two means:
+ *     * PPFrame::expand(), which provides expanded text
+ *     * The PPNode::split*() functions, which provide metadata about certain types of tree node
+ * @ingroup Parser
+ */
+interface PPNode {
+	/**
+	 * Get an array-type node containing the children of this node.
+	 * Returns false if this is not a tree node.
+	 * @return PPNode
+	 */
+	public function getChildren();
+
+	/**
+	 * Get the first child of a tree node. False if there isn't one.
+	 *
+	 * @return PPNode
+	 */
+	public function getFirstChild();
+
+	/**
+	 * Get the next sibling of any node. False if there isn't one
+	 * @return PPNode
+	 */
+	public function getNextSibling();
+
+	/**
+	 * Get all children of this tree node which have a given name.
+	 * Returns an array-type node, or false if this is not a tree node.
+	 * @param string $type
+	 * @return bool|PPNode
+	 */
+	public function getChildrenOfType( $type );
+
+	/**
+	 * Returns the length of the array, or false if this is not an array-type node
+	 */
+	public function getLength();
+
+	/**
+	 * Returns an item of an array-type node
+	 * @param int $i
+	 * @return bool|PPNode
+	 */
+	public function item( $i );
+
+	/**
+	 * Get the name of this node. The following names are defined here:
+	 *
+	 *    h             A heading node.
+	 *    template      A double-brace node.
+	 *    tplarg        A triple-brace node.
+	 *    title         The first argument to a template or tplarg node.
+	 *    part          Subsequent arguments to a template or tplarg node.
+	 *    #nodelist     An array-type node
+	 *
+	 * The subclass may define various other names for tree and leaf nodes.
+	 * @return string
+	 */
+	public function getName();
+
+	/**
+	 * Split a "<part>" node into an associative array containing:
+	 *    name          PPNode name
+	 *    index         String index
+	 *    value         PPNode value
+	 * @return array
+	 */
+	public function splitArg();
+
+	/**
+	 * Split an "<ext>" node into an associative array containing name, attr, inner and close
+	 * All values in the resulting array are PPNodes. Inner and close are optional.
+	 * @return array
+	 */
+	public function splitExt();
+
+	/**
+	 * Split an "<h>" node
+	 * @return array
+	 */
+	public function splitHeading();
+}
diff --git a/includes/parser/PPNode_DOM.php b/includes/parser/PPNode_DOM.php
new file mode 100644
index 0000000000..8a435bab67
--- /dev/null
+++ b/includes/parser/PPNode_DOM.php
@@ -0,0 +1,188 @@
+<?php
+/**
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ * @ingroup Parser
+ */
+
+/**
+ * @ingroup Parser
+ */
+// phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
+class PPNode_DOM implements PPNode {
+
+	/**
+	 * @var DOMElement
+	 */
+	public $node;
+	public $xpath;
+
+	public function __construct( $node, $xpath = false ) {
+		$this->node = $node;
+	}
+
+	/**
+	 * @return DOMXPath
+	 */
+	public function getXPath() {
+		if ( $this->xpath === null ) {
+			$this->xpath = new DOMXPath( $this->node->ownerDocument );
+		}
+		return $this->xpath;
+	}
+
+	public function __toString() {
+		if ( $this->node instanceof DOMNodeList ) {
+			$s = '';
+			foreach ( $this->node as $node ) {
+				$s .= $node->ownerDocument->saveXML( $node );
+			}
+		} else {
+			$s = $this->node->ownerDocument->saveXML( $this->node );
+		}
+		return $s;
+	}
+
+	/**
+	 * @return bool|PPNode_DOM
+	 */
+	public function getChildren() {
+		return $this->node->childNodes ? new self( $this->node->childNodes ) : false;
+	}
+
+	/**
+	 * @return bool|PPNode_DOM
+	 */
+	public function getFirstChild() {
+		return $this->node->firstChild ? new self( $this->node->firstChild ) : false;
+	}
+
+	/**
+	 * @return bool|PPNode_DOM
+	 */
+	public function getNextSibling() {
+		return $this->node->nextSibling ? new self( $this->node->nextSibling ) : false;
+	}
+
+	/**
+	 * @param string $type
+	 *
+	 * @return bool|PPNode_DOM
+	 */
+	public function getChildrenOfType( $type ) {
+		return new self( $this->getXPath()->query( $type, $this->node ) );
+	}
+
+	/**
+	 * @return int
+	 */
+	public function getLength() {
+		if ( $this->node instanceof DOMNodeList ) {
+			return $this->node->length;
+		} else {
+			return false;
+		}
+	}
+
+	/**
+	 * @param int $i
+	 * @return bool|PPNode_DOM
+	 */
+	public function item( $i ) {
+		$item = $this->node->item( $i );
+		return $item ? new self( $item ) : false;
+	}
+
+	/**
+	 * @return string
+	 */
+	public function getName() {
+		if ( $this->node instanceof DOMNodeList ) {
+			return '#nodelist';
+		} else {
+			return $this->node->nodeName;
+		}
+	}
+
+	/**
+	 * Split a "<part>" node into an associative array containing:
+	 *  - name          PPNode name
+	 *  - index         String index
+	 *  - value         PPNode value
+	 *
+	 * @throws MWException
+	 * @return array
+	 */
+	public function splitArg() {
+		$xpath = $this->getXPath();
+		$names = $xpath->query( 'name', $this->node );
+		$values = $xpath->query( 'value', $this->node );
+		if ( !$names->length || !$values->length ) {
+			throw new MWException( 'Invalid brace node passed to ' . __METHOD__ );
+		}
+		$name = $names->item( 0 );
+		$index = $name->getAttribute( 'index' );
+		return [
+			'name' => new self( $name ),
+			'index' => $index,
+			'value' => new self( $values->item( 0 ) ) ];
+	}
+
+	/**
+	 * Split an "<ext>" node into an associative array containing name, attr, inner and close
+	 * All values in the resulting array are PPNodes. Inner and close are optional.
+	 *
+	 * @throws MWException
+	 * @return array
+	 */
+	public function splitExt() {
+		$xpath = $this->getXPath();
+		$names = $xpath->query( 'name', $this->node );
+		$attrs = $xpath->query( 'attr', $this->node );
+		$inners = $xpath->query( 'inner', $this->node );
+		$closes = $xpath->query( 'close', $this->node );
+		if ( !$names->length || !$attrs->length ) {
+			throw new MWException( 'Invalid ext node passed to ' . __METHOD__ );
+		}
+		$parts = [
+			'name' => new self( $names->item( 0 ) ),
+			'attr' => new self( $attrs->item( 0 ) ) ];
+		if ( $inners->length ) {
+			$parts['inner'] = new self( $inners->item( 0 ) );
+		}
+		if ( $closes->length ) {
+			$parts['close'] = new self( $closes->item( 0 ) );
+		}
+		return $parts;
+	}
+
+	/**
+	 * Split a "<h>" node
+	 * @throws MWException
+	 * @return array
+	 */
+	public function splitHeading() {
+		if ( $this->getName() !== 'h' ) {
+			throw new MWException( 'Invalid h node passed to ' . __METHOD__ );
+		}
+		return [
+			'i' => $this->node->getAttribute( 'i' ),
+			'level' => $this->node->getAttribute( 'level' ),
+			'contents' => $this->getChildren()
+		];
+	}
+}
diff --git a/includes/parser/PPNode_Hash_Array.php b/includes/parser/PPNode_Hash_Array.php
new file mode 100644
index 0000000000..3892616ac4
--- /dev/null
+++ b/includes/parser/PPNode_Hash_Array.php
@@ -0,0 +1,77 @@
+<?php
+/**
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ * @ingroup Parser
+ */
+
+/**
+ * @ingroup Parser
+ */
+// phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
+class PPNode_Hash_Array implements PPNode {
+
+	public $value;
+
+	public function __construct( $value ) {
+		$this->value = $value;
+	}
+
+	public function __toString() {
+		return var_export( $this, true );
+	}
+
+	public function getLength() {
+		return count( $this->value );
+	}
+
+	public function item( $i ) {
+		return $this->value[$i];
+	}
+
+	public function getName() {
+		return '#nodelist';
+	}
+
+	public function getNextSibling() {
+		return false;
+	}
+
+	public function getChildren() {
+		return false;
+	}
+
+	public function getFirstChild() {
+		return false;
+	}
+
+	public function getChildrenOfType( $name ) {
+		return false;
+	}
+
+	public function splitArg() {
+		throw new MWException( __METHOD__ . ': not supported' );
+	}
+
+	public function splitExt() {
+		throw new MWException( __METHOD__ . ': not supported' );
+	}
+
+	public function splitHeading() {
+		throw new MWException( __METHOD__ . ': not supported' );
+	}
+}
diff --git a/includes/parser/PPNode_Hash_Attr.php b/includes/parser/PPNode_Hash_Attr.php
new file mode 100644
index 0000000000..91ba69d8d3
--- /dev/null
+++ b/includes/parser/PPNode_Hash_Attr.php
@@ -0,0 +1,92 @@
+<?php
+/**
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ * @ingroup Parser
+ */
+
+/**
+ * @ingroup Parser
+ */
+// phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
+class PPNode_Hash_Attr implements PPNode {
+
+	public $name, $value;
+	private $store, $index;
+
+	/**
+	 * Construct an object using the data from $store[$index]. The rest of the
+	 * store array can be accessed via getNextSibling().
+	 *
+	 * @param array $store
+	 * @param int $index
+	 */
+	public function __construct( array $store, $index ) {
+		$descriptor = $store[$index];
+		if ( $descriptor[PPNode_Hash_Tree::NAME][0] !== '@' ) {
+			throw new MWException( __METHOD__ . ': invalid name in attribute descriptor' );
+		}
+		$this->name = substr( $descriptor[PPNode_Hash_Tree::NAME], 1 );
+		$this->value = $descriptor[PPNode_Hash_Tree::CHILDREN][0];
+		$this->store = $store;
+		$this->index = $index;
+	}
+
+	public function __toString() {
+		return "<@{$this->name}>" . htmlspecialchars( $this->value ) . "</@{$this->name}>";
+	}
+
+	public function getName() {
+		return $this->name;
+	}
+
+	public function getNextSibling() {
+		return PPNode_Hash_Tree::factory( $this->store, $this->index + 1 );
+	}
+
+	public function getChildren() {
+		return false;
+	}
+
+	public function getFirstChild() {
+		return false;
+	}
+
+	public function getChildrenOfType( $name ) {
+		return false;
+	}
+
+	public function getLength() {
+		return false;
+	}
+
+	public function item( $i ) {
+		return false;
+	}
+
+	public function splitArg() {
+		throw new MWException( __METHOD__ . ': not supported' );
+	}
+
+	public function splitExt() {
+		throw new MWException( __METHOD__ . ': not supported' );
+	}
+
+	public function splitHeading() {
+		throw new MWException( __METHOD__ . ': not supported' );
+	}
+}
diff --git a/includes/parser/PPNode_Hash_Text.php b/includes/parser/PPNode_Hash_Text.php
new file mode 100644
index 0000000000..182982f35f
--- /dev/null
+++ b/includes/parser/PPNode_Hash_Text.php
@@ -0,0 +1,90 @@
+<?php
+/**
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ * @ingroup Parser
+ */
+
+/**
+ * @ingroup Parser
+ */
+// phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
+class PPNode_Hash_Text implements PPNode {
+
+	public $value;
+	private $store, $index;
+
+	/**
+	 * Construct an object using the data from $store[$index]. The rest of the
+	 * store array can be accessed via getNextSibling().
+	 *
+	 * @param array $store
+	 * @param int $index
+	 */
+	public function __construct( array $store, $index ) {
+		$this->value = $store[$index];
+		if ( !is_scalar( $this->value ) ) {
+			throw new MWException( __CLASS__ . ' given object instead of string' );
+		}
+		$this->store = $store;
+		$this->index = $index;
+	}
+
+	public function __toString() {
+		return htmlspecialchars( $this->value );
+	}
+
+	public function getNextSibling() {
+		return PPNode_Hash_Tree::factory( $this->store, $this->index + 1 );
+	}
+
+	public function getChildren() {
+		return false;
+	}
+
+	public function getFirstChild() {
+		return false;
+	}
+
+	public function getChildrenOfType( $name ) {
+		return false;
+	}
+
+	public function getLength() {
+		return false;
+	}
+
+	public function item( $i ) {
+		return false;
+	}
+
+	public function getName() {
+		return '#text';
+	}
+
+	public function splitArg() {
+		throw new MWException( __METHOD__ . ': not supported' );
+	}
+
+	public function splitExt() {
+		throw new MWException( __METHOD__ . ': not supported' );
+	}
+
+	public function splitHeading() {
+		throw new MWException( __METHOD__ . ': not supported' );
+	}
+}
diff --git a/includes/parser/PPNode_Hash_Tree.php b/includes/parser/PPNode_Hash_Tree.php
new file mode 100644
index 0000000000..e6cabf8e51
--- /dev/null
+++ b/includes/parser/PPNode_Hash_Tree.php
@@ -0,0 +1,369 @@
+<?php
+/**
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ * @ingroup Parser
+ */
+
+/**
+ * @ingroup Parser
+ */
+// phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
+class PPNode_Hash_Tree implements PPNode {
+
+	public $name;
+
+	/**
+	 * The store array for children of this node. It is "raw" in the sense that
+	 * nodes are two-element arrays ("descriptors") rather than PPNode_Hash_*
+	 * objects.
+	 */
+	private $rawChildren;
+
+	/**
+	 * The store array for the siblings of this node, including this node itself.
+	 */
+	private $store;
+
+	/**
+	 * The index into $this->store which contains the descriptor of this node.
+	 */
+	private $index;
+
+	/**
+	 * The offset of the name within descriptors, used in some places for
+	 * readability.
+	 */
+	const NAME = 0;
+
+	/**
+	 * The offset of the child list within descriptors, used in some places for
+	 * readability.
+	 */
+	const CHILDREN = 1;
+
+	/**
+	 * Construct an object using the data from $store[$index]. The rest of the
+	 * store array can be accessed via getNextSibling().
+	 *
+	 * @param array $store
+	 * @param int $index
+	 */
+	public function __construct( array $store, $index ) {
+		$this->store = $store;
+		$this->index = $index;
+		list( $this->name, $this->rawChildren ) = $this->store[$index];
+	}
+
+	/**
+	 * Construct an appropriate PPNode_Hash_* object with a class that depends
+	 * on what is at the relevant store index.
+	 *
+	 * @param array $store
+	 * @param int $index
+	 * @return PPNode_Hash_Tree|PPNode_Hash_Attr|PPNode_Hash_Text|false
+	 * @throws MWException
+	 */
+	public static function factory( array $store, $index ) {
+		if ( !isset( $store[$index] ) ) {
+			return false;
+		}
+
+		$descriptor = $store[$index];
+		if ( is_string( $descriptor ) ) {
+			$class = PPNode_Hash_Text::class;
+		} elseif ( is_array( $descriptor ) ) {
+			if ( $descriptor[self::NAME][0] === '@' ) {
+				$class = PPNode_Hash_Attr::class;
+			} else {
+				$class = self::class;
+			}
+		} else {
+			throw new MWException( __METHOD__ . ': invalid node descriptor' );
+		}
+		return new $class( $store, $index );
+	}
+
+	/**
+	 * Convert a node to XML, for debugging
+	 * @return string
+	 */
+	public function __toString() {
+		$inner = '';
+		$attribs = '';
+		for ( $node = $this->getFirstChild(); $node; $node = $node->getNextSibling() ) {
+			if ( $node instanceof PPNode_Hash_Attr ) {
+				$attribs .= ' ' . $node->name . '="' . htmlspecialchars( $node->value ) . '"';
+			} else {
+				$inner .= $node->__toString();
+			}
+		}
+		if ( $inner === '' ) {
+			return "<{$this->name}$attribs/>";
+		} else {
+			return "<{$this->name}$attribs>$inner</{$this->name}>";
+		}
+	}
+
+	/**
+	 * @return PPNode_Hash_Array
+	 */
+	public function getChildren() {
+		$children = [];
+		foreach ( $this->rawChildren as $i => $child ) {
+			$children[] = self::factory( $this->rawChildren, $i );
+		}
+		return new PPNode_Hash_Array( $children );
+	}
+
+	/**
+	 * Get the first child, or false if there is none. Note that this will
+	 * return a temporary proxy object: different instances will be returned
+	 * if this is called more than once on the same node.
+	 *
+	 * @return PPNode_Hash_Tree|PPNode_Hash_Attr|PPNode_Hash_Text|bool
+	 */
+	public function getFirstChild() {
+		if ( !isset( $this->rawChildren[0] ) ) {
+			return false;
+		} else {
+			return self::factory( $this->rawChildren, 0 );
+		}
+	}
+
+	/**
+	 * Get the next sibling, or false if there is none. Note that this will
+	 * return a temporary proxy object: different instances will be returned
+	 * if this is called more than once on the same node.
+	 *
+	 * @return PPNode_Hash_Tree|PPNode_Hash_Attr|PPNode_Hash_Text|bool
+	 */
+	public function getNextSibling() {
+		return self::factory( $this->store, $this->index + 1 );
+	}
+
+	/**
+	 * Get an array of the children with a given node name
+	 *
+	 * @param string $name
+	 * @return PPNode_Hash_Array
+	 */
+	public function getChildrenOfType( $name ) {
+		$children = [];
+		foreach ( $this->rawChildren as $i => $child ) {
+			if ( is_array( $child ) && $child[self::NAME] === $name ) {
+				$children[] = self::factory( $this->rawChildren, $i );
+			}
+		}
+		return new PPNode_Hash_Array( $children );
+	}
+
+	/**
+	 * Get the raw child array. For internal use.
+	 * @return array
+	 */
+	public function getRawChildren() {
+		return $this->rawChildren;
+	}
+
+	/**
+	 * @return bool
+	 */
+	public function getLength() {
+		return false;
+	}
+
+	/**
+	 * @param int $i
+	 * @return bool
+	 */
+	public function item( $i ) {
+		return false;
+	}
+
+	/**
+	 * @return string
+	 */
+	public function getName() {
+		return $this->name;
+	}
+
+	/**
+	 * Split a "<part>" node into an associative array containing:
+	 *  - name          PPNode name
+	 *  - index         String index
+	 *  - value         PPNode value
+	 *
+	 * @throws MWException
+	 * @return array
+	 */
+	public function splitArg() {
+		return self::splitRawArg( $this->rawChildren );
+	}
+
+	/**
+	 * Like splitArg() but for a raw child array. For internal use only.
+	 * @param array $children
+	 * @return array
+	 */
+	public static function splitRawArg( array $children ) {
+		$bits = [];
+		foreach ( $children as $i => $child ) {
+			if ( !is_array( $child ) ) {
+				continue;
+			}
+			if ( $child[self::NAME] === 'name' ) {
+				$bits['name'] = new self( $children, $i );
+				if ( isset( $child[self::CHILDREN][0][self::NAME] )
+					&& $child[self::CHILDREN][0][self::NAME] === '@index'
+				) {
+					$bits['index'] = $child[self::CHILDREN][0][self::CHILDREN][0];
+				}
+			} elseif ( $child[self::NAME] === 'value' ) {
+				$bits['value'] = new self( $children, $i );
+			}
+		}
+
+		if ( !isset( $bits['name'] ) ) {
+			throw new MWException( 'Invalid brace node passed to ' . __METHOD__ );
+		}
+		if ( !isset( $bits['index'] ) ) {
+			$bits['index'] = '';
+		}
+		return $bits;
+	}
+
+	/**
+	 * Split an "<ext>" node into an associative array containing name, attr, inner and close
+	 * All values in the resulting array are PPNodes. Inner and close are optional.
+	 *
+	 * @throws MWException
+	 * @return array
+	 */
+	public function splitExt() {
+		return self::splitRawExt( $this->rawChildren );
+	}
+
+	/**
+	 * Like splitExt() but for a raw child array. For internal use only.
+	 * @param array $children
+	 * @return array
+	 */
+	public static function splitRawExt( array $children ) {
+		$bits = [];
+		foreach ( $children as $i => $child ) {
+			if ( !is_array( $child ) ) {
+				continue;
+			}
+			switch ( $child[self::NAME] ) {
+				case 'name':
+					$bits['name'] = new self( $children, $i );
+					break;
+				case 'attr':
+					$bits['attr'] = new self( $children, $i );
+					break;
+				case 'inner':
+					$bits['inner'] = new self( $children, $i );
+					break;
+				case 'close':
+					$bits['close'] = new self( $children, $i );
+					break;
+			}
+		}
+		if ( !isset( $bits['name'] ) ) {
+			throw new MWException( 'Invalid ext node passed to ' . __METHOD__ );
+		}
+		return $bits;
+	}
+
+	/**
+	 * Split an "<h>" node
+	 *
+	 * @throws MWException
+	 * @return array
+	 */
+	public function splitHeading() {
+		if ( $this->name !== 'h' ) {
+			throw new MWException( 'Invalid h node passed to ' . __METHOD__ );
+		}
+		return self::splitRawHeading( $this->rawChildren );
+	}
+
+	/**
+	 * Like splitHeading() but for a raw child array. For internal use only.
+	 * @param array $children
+	 * @return array
+	 */
+	public static function splitRawHeading( array $children ) {
+		$bits = [];
+		foreach ( $children as $i => $child ) {
+			if ( !is_array( $child ) ) {
+				continue;
+			}
+			if ( $child[self::NAME] === '@i' ) {
+				$bits['i'] = $child[self::CHILDREN][0];
+			} elseif ( $child[self::NAME] === '@level' ) {
+				$bits['level'] = $child[self::CHILDREN][0];
+			}
+		}
+		if ( !isset( $bits['i'] ) ) {
+			throw new MWException( 'Invalid h node passed to ' . __METHOD__ );
+		}
+		return $bits;
+	}
+
+	/**
+	 * Split a "<template>" or "<tplarg>" node
+	 *
+	 * @throws MWException
+	 * @return array
+	 */
+	public function splitTemplate() {
+		return self::splitRawTemplate( $this->rawChildren );
+	}
+
+	/**
+	 * Like splitTemplate() but for a raw child array. For internal use only.
+	 * @param array $children
+	 * @return array
+	 */
+	public static function splitRawTemplate( array $children ) {
+		$parts = [];
+		$bits = [ 'lineStart' => '' ];
+		foreach ( $children as $i => $child ) {
+			if ( !is_array( $child ) ) {
+				continue;
+			}
+			switch ( $child[self::NAME] ) {
+				case 'title':
+					$bits['title'] = new self( $children, $i );
+					break;
+				case 'part':
+					$parts[] = new self( $children, $i );
+					break;
+				case '@lineStart':
+					$bits['lineStart'] = '1';
+					break;
+			}
+		}
+		if ( !isset( $bits['title'] ) ) {
+			throw new MWException( 'Invalid node passed to ' . __METHOD__ );
+		}
+		$bits['parts'] = new PPNode_Hash_Array( $parts );
+		return $bits;
+	}
+}
diff --git a/includes/parser/PPTemplateFrame_DOM.php b/includes/parser/PPTemplateFrame_DOM.php
new file mode 100644
index 0000000000..52cb9cb0f0
--- /dev/null
+++ b/includes/parser/PPTemplateFrame_DOM.php
@@ -0,0 +1,198 @@
+<?php
+/**
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ * @ingroup Parser
+ */
+
+/**
+ * Expansion frame with template arguments
+ * @ingroup Parser
+ */
+// phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
+class PPTemplateFrame_DOM extends PPFrame_DOM {
+
+	public $numberedArgs, $namedArgs;
+
+	/**
+	 * @var PPFrame_DOM
+	 */
+	public $parent;
+	public $numberedExpansionCache, $namedExpansionCache;
+
+	/**
+	 * @param Preprocessor $preprocessor
+	 * @param bool|PPFrame_DOM $parent
+	 * @param array $numberedArgs
+	 * @param array $namedArgs
+	 * @param bool|Title $title
+	 */
+	public function __construct( $preprocessor, $parent = false, $numberedArgs = [],
+		$namedArgs = [], $title = false
+	) {
+		parent::__construct( $preprocessor );
+
+		$this->parent = $parent;
+		$this->numberedArgs = $numberedArgs;
+		$this->namedArgs = $namedArgs;
+		$this->title = $title;
+		$pdbk = $title ? $title->getPrefixedDBkey() : false;
+		$this->titleCache = $parent->titleCache;
+		$this->titleCache[] = $pdbk;
+		$this->loopCheckHash = /*clone*/ $parent->loopCheckHash;
+		if ( $pdbk !== false ) {
+			$this->loopCheckHash[$pdbk] = true;
+		}
+		$this->depth = $parent->depth + 1;
+		$this->numberedExpansionCache = $this->namedExpansionCache = [];
+	}
+
+	public function __toString() {
+		$s = 'tplframe{';
+		$first = true;
+		$args = $this->numberedArgs + $this->namedArgs;
+		foreach ( $args as $name => $value ) {
+			if ( $first ) {
+				$first = false;
+			} else {
+				$s .= ', ';
+			}
+			$s .= "\"$name\":\"" .
+				str_replace( '"', '\\"', $value->ownerDocument->saveXML( $value ) ) . '"';
+		}
+		$s .= '}';
+		return $s;
+	}
+
+	/**
+	 * @throws MWException
+	 * @param string|int $key
+	 * @param string|PPNode_DOM|DOMDocument $root
+	 * @param int $flags
+	 * @return string
+	 */
+	public function cachedExpand( $key, $root, $flags = 0 ) {
+		if ( isset( $this->parent->childExpansionCache[$key] ) ) {
+			return $this->parent->childExpansionCache[$key];
+		}
+		$retval = $this->expand( $root, $flags );
+		if ( !$this->isVolatile() ) {
+			$this->parent->childExpansionCache[$key] = $retval;
+		}
+		return $retval;
+	}
+
+	/**
+	 * Returns true if there are no arguments in this frame
+	 *
+	 * @return bool
+	 */
+	public function isEmpty() {
+		return !count( $this->numberedArgs ) && !count( $this->namedArgs );
+	}
+
+	public function getArguments() {
+		$arguments = [];
+		foreach ( array_merge(
+				array_keys( $this->numberedArgs ),
+				array_keys( $this->namedArgs ) ) as $key ) {
+			$arguments[$key] = $this->getArgument( $key );
+		}
+		return $arguments;
+	}
+
+	public function getNumberedArguments() {
+		$arguments = [];
+		foreach ( array_keys( $this->numberedArgs ) as $key ) {
+			$arguments[$key] = $this->getArgument( $key );
+		}
+		return $arguments;
+	}
+
+	public function getNamedArguments() {
+		$arguments = [];
+		foreach ( array_keys( $this->namedArgs ) as $key ) {
+			$arguments[$key] = $this->getArgument( $key );
+		}
+		return $arguments;
+	}
+
+	/**
+	 * @param int $index
+	 * @return string|bool
+	 */
+	public function getNumberedArgument( $index ) {
+		if ( !isset( $this->numberedArgs[$index] ) ) {
+			return false;
+		}
+		if ( !isset( $this->numberedExpansionCache[$index] ) ) {
+			# No trimming for unnamed arguments
+			$this->numberedExpansionCache[$index] = $this->parent->expand(
+				$this->numberedArgs[$index],
+				PPFrame::STRIP_COMMENTS
+			);
+		}
+		return $this->numberedExpansionCache[$index];
+	}
+
+	/**
+	 * @param string $name
+	 * @return string|bool
+	 */
+	public function getNamedArgument( $name ) {
+		if ( !isset( $this->namedArgs[$name] ) ) {
+			return false;
+		}
+		if ( !isset( $this->namedExpansionCache[$name] ) ) {
+			# Trim named arguments post-expand, for backwards compatibility
+			$this->namedExpansionCache[$name] = trim(
+				$this->parent->expand( $this->namedArgs[$name], PPFrame::STRIP_COMMENTS ) );
+		}
+		return $this->namedExpansionCache[$name];
+	}
+
+	/**
+	 * @param int|string $name
+	 * @return string|bool
+	 */
+	public function getArgument( $name ) {
+		$text = $this->getNumberedArgument( $name );
+		if ( $text === false ) {
+			$text = $this->getNamedArgument( $name );
+		}
+		return $text;
+	}
+
+	/**
+	 * Return true if the frame is a template frame
+	 *
+	 * @return bool
+	 */
+	public function isTemplate() {
+		return true;
+	}
+
+	public function setVolatile( $flag = true ) {
+		parent::setVolatile( $flag );
+		$this->parent->setVolatile( $flag );
+	}
+
+	public function setTTL( $ttl ) {
+		parent::setTTL( $ttl );
+		$this->parent->setTTL( $ttl );
+	}
+}
diff --git a/includes/parser/PPTemplateFrame_Hash.php b/includes/parser/PPTemplateFrame_Hash.php
new file mode 100644
index 0000000000..df740cf22d
--- /dev/null
+++ b/includes/parser/PPTemplateFrame_Hash.php
@@ -0,0 +1,202 @@
+<?php
+/**
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ * @ingroup Parser
+ */
+
+/**
+ * Expansion frame with template arguments
+ * @ingroup Parser
+ */
+// phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
+class PPTemplateFrame_Hash extends PPFrame_Hash {
+
+	public $numberedArgs, $namedArgs, $parent;
+	public $numberedExpansionCache, $namedExpansionCache;
+
+	/**
+	 * @param Preprocessor $preprocessor
+	 * @param bool|PPFrame $parent
+	 * @param array $numberedArgs
+	 * @param array $namedArgs
+	 * @param bool|Title $title
+	 */
+	public function __construct( $preprocessor, $parent = false, $numberedArgs = [],
+		$namedArgs = [], $title = false
+	) {
+		parent::__construct( $preprocessor );
+
+		$this->parent = $parent;
+		$this->numberedArgs = $numberedArgs;
+		$this->namedArgs = $namedArgs;
+		$this->title = $title;
+		$pdbk = $title ? $title->getPrefixedDBkey() : false;
+		$this->titleCache = $parent->titleCache;
+		$this->titleCache[] = $pdbk;
+		$this->loopCheckHash = /*clone*/ $parent->loopCheckHash;
+		if ( $pdbk !== false ) {
+			$this->loopCheckHash[$pdbk] = true;
+		}
+		$this->depth = $parent->depth + 1;
+		$this->numberedExpansionCache = $this->namedExpansionCache = [];
+	}
+
+	public function __toString() {
+		$s = 'tplframe{';
+		$first = true;
+		$args = $this->numberedArgs + $this->namedArgs;
+		foreach ( $args as $name => $value ) {
+			if ( $first ) {
+				$first = false;
+			} else {
+				$s .= ', ';
+			}
+			$s .= "\"$name\":\"" .
+				str_replace( '"', '\\"', $value->__toString() ) . '"';
+		}
+		$s .= '}';
+		return $s;
+	}
+
+	/**
+	 * @throws MWException
+	 * @param string|int $key
+	 * @param string|PPNode $root
+	 * @param int $flags
+	 * @return string
+	 */
+	public function cachedExpand( $key, $root, $flags = 0 ) {
+		if ( isset( $this->parent->childExpansionCache[$key] ) ) {
+			return $this->parent->childExpansionCache[$key];
+		}
+		$retval = $this->expand( $root, $flags );
+		if ( !$this->isVolatile() ) {
+			$this->parent->childExpansionCache[$key] = $retval;
+		}
+		return $retval;
+	}
+
+	/**
+	 * Returns true if there are no arguments in this frame
+	 *
+	 * @return bool
+	 */
+	public function isEmpty() {
+		return !count( $this->numberedArgs ) && !count( $this->namedArgs );
+	}
+
+	/**
+	 * @return array
+	 */
+	public function getArguments() {
+		$arguments = [];
+		foreach ( array_merge(
+				array_keys( $this->numberedArgs ),
+				array_keys( $this->namedArgs ) ) as $key ) {
+			$arguments[$key] = $this->getArgument( $key );
+		}
+		return $arguments;
+	}
+
+	/**
+	 * @return array
+	 */
+	public function getNumberedArguments() {
+		$arguments = [];
+		foreach ( array_keys( $this->numberedArgs ) as $key ) {
+			$arguments[$key] = $this->getArgument( $key );
+		}
+		return $arguments;
+	}
+
+	/**
+	 * @return array
+	 */
+	public function getNamedArguments() {
+		$arguments = [];
+		foreach ( array_keys( $this->namedArgs ) as $key ) {
+			$arguments[$key] = $this->getArgument( $key );
+		}
+		return $arguments;
+	}
+
+	/**
+	 * @param int $index
+	 * @return string|bool
+	 */
+	public function getNumberedArgument( $index ) {
+		if ( !isset( $this->numberedArgs[$index] ) ) {
+			return false;
+		}
+		if ( !isset( $this->numberedExpansionCache[$index] ) ) {
+			# No trimming for unnamed arguments
+			$this->numberedExpansionCache[$index] = $this->parent->expand(
+				$this->numberedArgs[$index],
+				PPFrame::STRIP_COMMENTS
+			);
+		}
+		return $this->numberedExpansionCache[$index];
+	}
+
+	/**
+	 * @param string $name
+	 * @return string|bool
+	 */
+	public function getNamedArgument( $name ) {
+		if ( !isset( $this->namedArgs[$name] ) ) {
+			return false;
+		}
+		if ( !isset( $this->namedExpansionCache[$name] ) ) {
+			# Trim named arguments post-expand, for backwards compatibility
+			$this->namedExpansionCache[$name] = trim(
+				$this->parent->expand( $this->namedArgs[$name], PPFrame::STRIP_COMMENTS ) );
+		}
+		return $this->namedExpansionCache[$name];
+	}
+
+	/**
+	 * @param int|string $name
+	 * @return string|bool
+	 */
+	public function getArgument( $name ) {
+		$text = $this->getNumberedArgument( $name );
+		if ( $text === false ) {
+			$text = $this->getNamedArgument( $name );
+		}
+		return $text;
+	}
+
+	/**
+	 * Return true if the frame is a template frame
+	 *
+	 * @return bool
+	 */
+	public function isTemplate() {
+		return true;
+	}
+
+	public function setVolatile( $flag = true ) {
+		parent::setVolatile( $flag );
+		$this->parent->setVolatile( $flag );
+	}
+
+	public function setTTL( $ttl ) {
+		parent::setTTL( $ttl );
+		$this->parent->setTTL( $ttl );
+	}
+}
diff --git a/includes/parser/Preprocessor.php b/includes/parser/Preprocessor.php
index bdfedd6441..b321078dcd 100644
--- a/includes/parser/Preprocessor.php
+++ b/includes/parser/Preprocessor.php
@@ -164,279 +164,3 @@ abstract class Preprocessor {
 	 */
 	abstract public function preprocessToObj( $text, $flags = 0 );
 }
-
-/**
- * @ingroup Parser
- */
-interface PPFrame {
-	const NO_ARGS = 1;
-	const NO_TEMPLATES = 2;
-	const STRIP_COMMENTS = 4;
-	const NO_IGNORE = 8;
-	const RECOVER_COMMENTS = 16;
-	const NO_TAGS = 32;
-
-	const RECOVER_ORIG = self::NO_ARGS | self::NO_TEMPLATES | self::NO_IGNORE |
-		self::RECOVER_COMMENTS | self::NO_TAGS;
-
-	/** This constant exists when $indexOffset is supported in newChild() */
-	const SUPPORTS_INDEX_OFFSET = 1;
-
-	/**
-	 * Create a child frame
-	 *
-	 * @param array|bool $args
-	 * @param bool|Title $title
-	 * @param int $indexOffset A number subtracted from the index attributes of the arguments
-	 *
-	 * @return PPFrame
-	 */
-	public function newChild( $args = false, $title = false, $indexOffset = 0 );
-
-	/**
-	 * Expand a document tree node, caching the result on its parent with the given key
-	 * @param string|int $key
-	 * @param string|PPNode $root
-	 * @param int $flags
-	 * @return string
-	 */
-	public function cachedExpand( $key, $root, $flags = 0 );
-
-	/**
-	 * Expand a document tree node
-	 * @param string|PPNode $root
-	 * @param int $flags
-	 * @return string
-	 */
-	public function expand( $root, $flags = 0 );
-
-	/**
-	 * Implode with flags for expand()
-	 * @param string $sep
-	 * @param int $flags
-	 * @param string|PPNode $args,...
-	 * @return string
-	 */
-	public function implodeWithFlags( $sep, $flags /*, ... */ );
-
-	/**
-	 * Implode with no flags specified
-	 * @param string $sep
-	 * @param string|PPNode $args,...
-	 * @return string
-	 */
-	public function implode( $sep /*, ... */ );
-
-	/**
-	 * Makes an object that, when expand()ed, will be the same as one obtained
-	 * with implode()
-	 * @param string $sep
-	 * @param string|PPNode $args,...
-	 * @return PPNode
-	 */
-	public function virtualImplode( $sep /*, ... */ );
-
-	/**
-	 * Virtual implode with brackets
-	 * @param string $start
-	 * @param string $sep
-	 * @param string $end
-	 * @param string|PPNode $args,...
-	 * @return PPNode
-	 */
-	public function virtualBracketedImplode( $start, $sep, $end /*, ... */ );
-
-	/**
-	 * Returns true if there are no arguments in this frame
-	 *
-	 * @return bool
-	 */
-	public function isEmpty();
-
-	/**
-	 * Returns all arguments of this frame
-	 * @return array
-	 */
-	public function getArguments();
-
-	/**
-	 * Returns all numbered arguments of this frame
-	 * @return array
-	 */
-	public function getNumberedArguments();
-
-	/**
-	 * Returns all named arguments of this frame
-	 * @return array
-	 */
-	public function getNamedArguments();
-
-	/**
-	 * Get an argument to this frame by name
-	 * @param int|string $name
-	 * @return string|bool
-	 */
-	public function getArgument( $name );
-
-	/**
-	 * Returns true if the infinite loop check is OK, false if a loop is detected
-	 *
-	 * @param Title $title
-	 * @return bool
-	 */
-	public function loopCheck( $title );
-
-	/**
-	 * Return true if the frame is a template frame
-	 * @return bool
-	 */
-	public function isTemplate();
-
-	/**
-	 * Set the "volatile" flag.
-	 *
-	 * Note that this is somewhat of a "hack" in order to make extensions
-	 * with side effects (such as Cite) work with the PHP parser. New
-	 * extensions should be written in a way that they do not need this
-	 * function, because other parsers (such as Parsoid) are not guaranteed
-	 * to respect it, and it may be removed in the future.
-	 *
-	 * @param bool $flag
-	 */
-	public function setVolatile( $flag = true );
-
-	/**
-	 * Get the "volatile" flag.
-	 *
-	 * Callers should avoid caching the result of an expansion if it has the
-	 * volatile flag set.
-	 *
-	 * @see self::setVolatile()
-	 * @return bool
-	 */
-	public function isVolatile();
-
-	/**
-	 * Get the TTL of the frame's output.
-	 *
-	 * This is the maximum amount of time, in seconds, that this frame's
-	 * output should be cached for. A value of null indicates that no
-	 * maximum has been specified.
-	 *
-	 * Note that this TTL only applies to caching frames as parts of pages.
-	 * It is not relevant to caching the entire rendered output of a page.
-	 *
-	 * @return int|null
-	 */
-	public function getTTL();
-
-	/**
-	 * Set the TTL of the output of this frame and all of its ancestors.
-	 * Has no effect if the new TTL is greater than the one already set.
-	 * Note that it is the caller's responsibility to change the cache
-	 * expiry of the page as a whole, if such behavior is desired.
-	 *
-	 * @see self::getTTL()
-	 * @param int $ttl
-	 */
-	public function setTTL( $ttl );
-
-	/**
-	 * Get a title of frame
-	 *
-	 * @return Title
-	 */
-	public function getTitle();
-}
-
-/**
- * There are three types of nodes:
- *     * Tree nodes, which have a name and contain other nodes as children
- *     * Array nodes, which also contain other nodes but aren't considered part of a tree
- *     * Leaf nodes, which contain the actual data
- *
- * This interface provides access to the tree structure and to the contents of array nodes,
- * but it does not provide access to the internal structure of leaf nodes. Access to leaf
- * data is provided via two means:
- *     * PPFrame::expand(), which provides expanded text
- *     * The PPNode::split*() functions, which provide metadata about certain types of tree node
- * @ingroup Parser
- */
-interface PPNode {
-	/**
-	 * Get an array-type node containing the children of this node.
-	 * Returns false if this is not a tree node.
-	 * @return PPNode
-	 */
-	public function getChildren();
-
-	/**
-	 * Get the first child of a tree node. False if there isn't one.
-	 *
-	 * @return PPNode
-	 */
-	public function getFirstChild();
-
-	/**
-	 * Get the next sibling of any node. False if there isn't one
-	 * @return PPNode
-	 */
-	public function getNextSibling();
-
-	/**
-	 * Get all children of this tree node which have a given name.
-	 * Returns an array-type node, or false if this is not a tree node.
-	 * @param string $type
-	 * @return bool|PPNode
-	 */
-	public function getChildrenOfType( $type );
-
-	/**
-	 * Returns the length of the array, or false if this is not an array-type node
-	 */
-	public function getLength();
-
-	/**
-	 * Returns an item of an array-type node
-	 * @param int $i
-	 * @return bool|PPNode
-	 */
-	public function item( $i );
-
-	/**
-	 * Get the name of this node. The following names are defined here:
-	 *
-	 *    h             A heading node.
-	 *    template      A double-brace node.
-	 *    tplarg        A triple-brace node.
-	 *    title         The first argument to a template or tplarg node.
-	 *    part          Subsequent arguments to a template or tplarg node.
-	 *    #nodelist     An array-type node
-	 *
-	 * The subclass may define various other names for tree and leaf nodes.
-	 * @return string
-	 */
-	public function getName();
-
-	/**
-	 * Split a "<part>" node into an associative array containing:
-	 *    name          PPNode name
-	 *    index         String index
-	 *    value         PPNode value
-	 * @return array
-	 */
-	public function splitArg();
-
-	/**
-	 * Split an "<ext>" node into an associative array containing name, attr, inner and close
-	 * All values in the resulting array are PPNodes. Inner and close are optional.
-	 * @return array
-	 */
-	public function splitExt();
-
-	/**
-	 * Split an "<h>" node
-	 * @return array
-	 */
-	public function splitHeading();
-}
diff --git a/includes/parser/Preprocessor_DOM.php b/includes/parser/Preprocessor_DOM.php
index c27a635e04..0f0496beac 100644
--- a/includes/parser/Preprocessor_DOM.php
+++ b/includes/parser/Preprocessor_DOM.php
@@ -823,1231 +823,3 @@ class Preprocessor_DOM extends Preprocessor {
 		return $xml;
 	}
 }
-
-/**
- * Stack class to help Preprocessor::preprocessToObj()
- * @ingroup Parser
- */
-class PPDStack {
-	public $stack, $rootAccum;
-
-	/**
-	 * @var PPDStack
-	 */
-	public $top;
-	public $out;
-	public $elementClass = PPDStackElement::class;
-
-	public static $false = false;
-
-	public function __construct() {
-		$this->stack = [];
-		$this->top = false;
-		$this->rootAccum = '';
-		$this->accum =& $this->rootAccum;
-	}
-
-	/**
-	 * @return int
-	 */
-	public function count() {
-		return count( $this->stack );
-	}
-
-	public function &getAccum() {
-		return $this->accum;
-	}
-
-	/**
-	 * @return bool|PPDPart
-	 */
-	public function getCurrentPart() {
-		if ( $this->top === false ) {
-			return false;
-		} else {
-			return $this->top->getCurrentPart();
-		}
-	}
-
-	public function push( $data ) {
-		if ( $data instanceof $this->elementClass ) {
-			$this->stack[] = $data;
-		} else {
-			$class = $this->elementClass;
-			$this->stack[] = new $class( $data );
-		}
-		$this->top = $this->stack[count( $this->stack ) - 1];
-		$this->accum =& $this->top->getAccum();
-	}
-
-	public function pop() {
-		if ( $this->stack === [] ) {
-			throw new MWException( __METHOD__ . ': no elements remaining' );
-		}
-		$temp = array_pop( $this->stack );
-
-		if ( count( $this->stack ) ) {
-			$this->top = $this->stack[count( $this->stack ) - 1];
-			$this->accum =& $this->top->getAccum();
-		} else {
-			$this->top = self::$false;
-			$this->accum =& $this->rootAccum;
-		}
-		return $temp;
-	}
-
-	public function addPart( $s = '' ) {
-		$this->top->addPart( $s );
-		$this->accum =& $this->top->getAccum();
-	}
-
-	/**
-	 * @return array
-	 */
-	public function getFlags() {
-		if ( $this->stack === [] ) {
-			return [
-				'findEquals' => false,
-				'findPipe' => false,
-				'inHeading' => false,
-			];
-		} else {
-			return $this->top->getFlags();
-		}
-	}
-}
-
-/**
- * @ingroup Parser
- */
-class PPDStackElement {
-	/**
-	 * @var string Opening character (\n for heading)
-	 */
-	public $open;
-
-	/**
-	 * @var string Matching closing character
-	 */
-	public $close;
-
-	/**
-	 * @var string Saved prefix that may affect later processing,
-	 *  e.g. to differentiate `-{{{{` and `{{{{` after later seeing `}}}`.
-	 */
-	public $savedPrefix = '';
-
-	/**
-	 * @var int Number of opening characters found (number of "=" for heading)
-	 */
-	public $count;
-
-	/**
-	 * @var PPDPart[] Array of PPDPart objects describing pipe-separated parts.
-	 */
-	public $parts;
-
-	/**
-	 * @var bool True if the open char appeared at the start of the input line.
-	 *  Not set for headings.
-	 */
-	public $lineStart;
-
-	public $partClass = PPDPart::class;
-
-	public function __construct( $data = [] ) {
-		$class = $this->partClass;
-		$this->parts = [ new $class ];
-
-		foreach ( $data as $name => $value ) {
-			$this->$name = $value;
-		}
-	}
-
-	public function &getAccum() {
-		return $this->parts[count( $this->parts ) - 1]->out;
-	}
-
-	public function addPart( $s = '' ) {
-		$class = $this->partClass;
-		$this->parts[] = new $class( $s );
-	}
-
-	/**
-	 * @return PPDPart
-	 */
-	public function getCurrentPart() {
-		return $this->parts[count( $this->parts ) - 1];
-	}
-
-	/**
-	 * @return array
-	 */
-	public function getFlags() {
-		$partCount = count( $this->parts );
-		$findPipe = $this->open != "\n" && $this->open != '[';
-		return [
-			'findPipe' => $findPipe,
-			'findEquals' => $findPipe && $partCount > 1 && !isset( $this->parts[$partCount - 1]->eqpos ),
-			'inHeading' => $this->open == "\n",
-		];
-	}
-
-	/**
-	 * Get the output string that would result if the close is not found.
-	 *
-	 * @param bool|int $openingCount
-	 * @return string
-	 */
-	public function breakSyntax( $openingCount = false ) {
-		if ( $this->open == "\n" ) {
-			$s = $this->savedPrefix . $this->parts[0]->out;
-		} else {
-			if ( $openingCount === false ) {
-				$openingCount = $this->count;
-			}
-			$s = substr( $this->open, 0, -1 );
-			$s .= str_repeat(
-				substr( $this->open, -1 ),
-				$openingCount - strlen( $s )
-			);
-			$s = $this->savedPrefix . $s;
-			$first = true;
-			foreach ( $this->parts as $part ) {
-				if ( $first ) {
-					$first = false;
-				} else {
-					$s .= '|';
-				}
-				$s .= $part->out;
-			}
-		}
-		return $s;
-	}
-}
-
-/**
- * @ingroup Parser
- */
-class PPDPart {
-	/**
-	 * @var string Output accumulator string
-	 */
-	public $out;
-
-	// Optional member variables:
-	//   eqpos        Position of equals sign in output accumulator
-	//   commentEnd   Past-the-end input pointer for the last comment encountered
-	//   visualEnd    Past-the-end input pointer for the end of the accumulator minus comments
-
-	public function __construct( $out = '' ) {
-		$this->out = $out;
-	}
-}
-
-/**
- * An expansion frame, used as a context to expand the result of preprocessToObj()
- * @ingroup Parser
- */
-// phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
-class PPFrame_DOM implements PPFrame {
-
-	/**
-	 * @var Preprocessor
-	 */
-	public $preprocessor;
-
-	/**
-	 * @var Parser
-	 */
-	public $parser;
-
-	/**
-	 * @var Title
-	 */
-	public $title;
-	public $titleCache;
-
-	/**
-	 * Hashtable listing templates which are disallowed for expansion in this frame,
-	 * having been encountered previously in parent frames.
-	 */
-	public $loopCheckHash;
-
-	/**
-	 * Recursion depth of this frame, top = 0
-	 * Note that this is NOT the same as expansion depth in expand()
-	 */
-	public $depth;
-
-	private $volatile = false;
-	private $ttl = null;
-
-	/**
-	 * @var array
-	 */
-	protected $childExpansionCache;
-
-	/**
-	 * Construct a new preprocessor frame.
-	 * @param Preprocessor $preprocessor The parent preprocessor
-	 */
-	public function __construct( $preprocessor ) {
-		$this->preprocessor = $preprocessor;
-		$this->parser = $preprocessor->parser;
-		$this->title = $this->parser->mTitle;
-		$this->titleCache = [ $this->title ? $this->title->getPrefixedDBkey() : false ];
-		$this->loopCheckHash = [];
-		$this->depth = 0;
-		$this->childExpansionCache = [];
-	}
-
-	/**
-	 * Create a new child frame
-	 * $args is optionally a multi-root PPNode or array containing the template arguments
-	 *
-	 * @param bool|array $args
-	 * @param Title|bool $title
-	 * @param int $indexOffset
-	 * @return PPTemplateFrame_DOM
-	 */
-	public function newChild( $args = false, $title = false, $indexOffset = 0 ) {
-		$namedArgs = [];
-		$numberedArgs = [];
-		if ( $title === false ) {
-			$title = $this->title;
-		}
-		if ( $args !== false ) {
-			$xpath = false;
-			if ( $args instanceof PPNode ) {
-				$args = $args->node;
-			}
-			foreach ( $args as $arg ) {
-				if ( $arg instanceof PPNode ) {
-					$arg = $arg->node;
-				}
-				if ( !$xpath || $xpath->document !== $arg->ownerDocument ) {
-					$xpath = new DOMXPath( $arg->ownerDocument );
-				}
-
-				$nameNodes = $xpath->query( 'name', $arg );
-				$value = $xpath->query( 'value', $arg );
-				if ( $nameNodes->item( 0 )->hasAttributes() ) {
-					// Numbered parameter
-					$index = $nameNodes->item( 0 )->attributes->getNamedItem( 'index' )->textContent;
-					$index = $index - $indexOffset;
-					if ( isset( $namedArgs[$index] ) || isset( $numberedArgs[$index] ) ) {
-						$this->parser->getOutput()->addWarning( wfMessage( 'duplicate-args-warning',
-							wfEscapeWikiText( $this->title ),
-							wfEscapeWikiText( $title ),
-							wfEscapeWikiText( $index ) )->text() );
-						$this->parser->addTrackingCategory( 'duplicate-args-category' );
-					}
-					$numberedArgs[$index] = $value->item( 0 );
-					unset( $namedArgs[$index] );
-				} else {
-					// Named parameter
-					$name = trim( $this->expand( $nameNodes->item( 0 ), PPFrame::STRIP_COMMENTS ) );
-					if ( isset( $namedArgs[$name] ) || isset( $numberedArgs[$name] ) ) {
-						$this->parser->getOutput()->addWarning( wfMessage( 'duplicate-args-warning',
-							wfEscapeWikiText( $this->title ),
-							wfEscapeWikiText( $title ),
-							wfEscapeWikiText( $name ) )->text() );
-						$this->parser->addTrackingCategory( 'duplicate-args-category' );
-					}
-					$namedArgs[$name] = $value->item( 0 );
-					unset( $numberedArgs[$name] );
-				}
-			}
-		}
-		return new PPTemplateFrame_DOM( $this->preprocessor, $this, $numberedArgs, $namedArgs, $title );
-	}
-
-	/**
-	 * @throws MWException
-	 * @param string|int $key
-	 * @param string|PPNode_DOM|DOMDocument $root
-	 * @param int $flags
-	 * @return string
-	 */
-	public function cachedExpand( $key, $root, $flags = 0 ) {
-		// we don't have a parent, so we don't have a cache
-		return $this->expand( $root, $flags );
-	}
-
-	/**
-	 * @throws MWException
-	 * @param string|PPNode_DOM|DOMDocument $root
-	 * @param int $flags
-	 * @return string
-	 */
-	public function expand( $root, $flags = 0 ) {
-		static $expansionDepth = 0;
-		if ( is_string( $root ) ) {
-			return $root;
-		}
-
-		if ( ++$this->parser->mPPNodeCount > $this->parser->mOptions->getMaxPPNodeCount() ) {
-			$this->parser->limitationWarn( 'node-count-exceeded',
-				$this->parser->mPPNodeCount,
-				$this->parser->mOptions->getMaxPPNodeCount()
-			);
-			return '<span class="error">Node-count limit exceeded</span>';
-		}
-
-		if ( $expansionDepth > $this->parser->mOptions->getMaxPPExpandDepth() ) {
-			$this->parser->limitationWarn( 'expansion-depth-exceeded',
-				$expansionDepth,
-				$this->parser->mOptions->getMaxPPExpandDepth()
-			);
-			return '<span class="error">Expansion depth limit exceeded</span>';
-		}
-		++$expansionDepth;
-		if ( $expansionDepth > $this->parser->mHighestExpansionDepth ) {
-			$this->parser->mHighestExpansionDepth = $expansionDepth;
-		}
-
-		if ( $root instanceof PPNode_DOM ) {
-			$root = $root->node;
-		}
-		if ( $root instanceof DOMDocument ) {
-			$root = $root->documentElement;
-		}
-
-		$outStack = [ '', '' ];
-		$iteratorStack = [ false, $root ];
-		$indexStack = [ 0, 0 ];
-
-		while ( count( $iteratorStack ) > 1 ) {
-			$level = count( $outStack ) - 1;
-			$iteratorNode =& $iteratorStack[$level];
-			$out =& $outStack[$level];
-			$index =& $indexStack[$level];
-
-			if ( $iteratorNode instanceof PPNode_DOM ) {
-				$iteratorNode = $iteratorNode->node;
-			}
-
-			if ( is_array( $iteratorNode ) ) {
-				if ( $index >= count( $iteratorNode ) ) {
-					// All done with this iterator
-					$iteratorStack[$level] = false;
-					$contextNode = false;
-				} else {
-					$contextNode = $iteratorNode[$index];
-					$index++;
-				}
-			} elseif ( $iteratorNode instanceof DOMNodeList ) {
-				if ( $index >= $iteratorNode->length ) {
-					// All done with this iterator
-					$iteratorStack[$level] = false;
-					$contextNode = false;
-				} else {
-					$contextNode = $iteratorNode->item( $index );
-					$index++;
-				}
-			} else {
-				// Copy to $contextNode and then delete from iterator stack,
-				// because this is not an iterator but we do have to execute it once
-				$contextNode = $iteratorStack[$level];
-				$iteratorStack[$level] = false;
-			}
-
-			if ( $contextNode instanceof PPNode_DOM ) {
-				$contextNode = $contextNode->node;
-			}
-
-			$newIterator = false;
-
-			if ( $contextNode === false ) {
-				// nothing to do
-			} elseif ( is_string( $contextNode ) ) {
-				$out .= $contextNode;
-			} elseif ( is_array( $contextNode ) || $contextNode instanceof DOMNodeList ) {
-				$newIterator = $contextNode;
-			} elseif ( $contextNode instanceof DOMNode ) {
-				if ( $contextNode->nodeType == XML_TEXT_NODE ) {
-					$out .= $contextNode->nodeValue;
-				} elseif ( $contextNode->nodeName == 'template' ) {
-					# Double-brace expansion
-					$xpath = new DOMXPath( $contextNode->ownerDocument );
-					$titles = $xpath->query( 'title', $contextNode );
-					$title = $titles->item( 0 );
-					$parts = $xpath->query( 'part', $contextNode );
-					if ( $flags & PPFrame::NO_TEMPLATES ) {
-						$newIterator = $this->virtualBracketedImplode( '{{', '|', '}}', $title, $parts );
-					} else {
-						$lineStart = $contextNode->getAttribute( 'lineStart' );
-						$params = [
-							'title' => new PPNode_DOM( $title ),
-							'parts' => new PPNode_DOM( $parts ),
-							'lineStart' => $lineStart ];
-						$ret = $this->parser->braceSubstitution( $params, $this );
-						if ( isset( $ret['object'] ) ) {
-							$newIterator = $ret['object'];
-						} else {
-							$out .= $ret['text'];
-						}
-					}
-				} elseif ( $contextNode->nodeName == 'tplarg' ) {
-					# Triple-brace expansion
-					$xpath = new DOMXPath( $contextNode->ownerDocument );
-					$titles = $xpath->query( 'title', $contextNode );
-					$title = $titles->item( 0 );
-					$parts = $xpath->query( 'part', $contextNode );
-					if ( $flags & PPFrame::NO_ARGS ) {
-						$newIterator = $this->virtualBracketedImplode( '{{{', '|', '}}}', $title, $parts );
-					} else {
-						$params = [
-							'title' => new PPNode_DOM( $title ),
-							'parts' => new PPNode_DOM( $parts ) ];
-						$ret = $this->parser->argSubstitution( $params, $this );
-						if ( isset( $ret['object'] ) ) {
-							$newIterator = $ret['object'];
-						} else {
-							$out .= $ret['text'];
-						}
-					}
-				} elseif ( $contextNode->nodeName == 'comment' ) {
-					# HTML-style comment
-					# Remove it in HTML, pre+remove and STRIP_COMMENTS modes
-					# Not in RECOVER_COMMENTS mode (msgnw) though.
-					if ( ( $this->parser->ot['html']
-						|| ( $this->parser->ot['pre'] && $this->parser->mOptions->getRemoveComments() )
-						|| ( $flags & PPFrame::STRIP_COMMENTS )
-						) && !( $flags & PPFrame::RECOVER_COMMENTS )
-					) {
-						$out .= '';
-					} elseif ( $this->parser->ot['wiki'] && !( $flags & PPFrame::RECOVER_COMMENTS ) ) {
-						# Add a strip marker in PST mode so that pstPass2() can
-						# run some old-fashioned regexes on the result.
-						# Not in RECOVER_COMMENTS mode (extractSections) though.
-						$out .= $this->parser->insertStripItem( $contextNode->textContent );
-					} else {
-						# Recover the literal comment in RECOVER_COMMENTS and pre+no-remove
-						$out .= $contextNode->textContent;
-					}
-				} elseif ( $contextNode->nodeName == 'ignore' ) {
-					# Output suppression used by <includeonly> etc.
-					# OT_WIKI will only respect <ignore> in substed templates.
-					# The other output types respect it unless NO_IGNORE is set.
-					# extractSections() sets NO_IGNORE and so never respects it.
-					if ( ( !isset( $this->parent ) && $this->parser->ot['wiki'] )
-						|| ( $flags & PPFrame::NO_IGNORE )
-					) {
-						$out .= $contextNode->textContent;
-					} else {
-						$out .= '';
-					}
-				} elseif ( $contextNode->nodeName == 'ext' ) {
-					# Extension tag
-					$xpath = new DOMXPath( $contextNode->ownerDocument );
-					$names = $xpath->query( 'name', $contextNode );
-					$attrs = $xpath->query( 'attr', $contextNode );
-					$inners = $xpath->query( 'inner', $contextNode );
-					$closes = $xpath->query( 'close', $contextNode );
-					if ( $flags & PPFrame::NO_TAGS ) {
-						$s = '<' . $this->expand( $names->item( 0 ), $flags );
-						if ( $attrs->length > 0 ) {
-							$s .= $this->expand( $attrs->item( 0 ), $flags );
-						}
-						if ( $inners->length > 0 ) {
-							$s .= '>' . $this->expand( $inners->item( 0 ), $flags );
-							if ( $closes->length > 0 ) {
-								$s .= $this->expand( $closes->item( 0 ), $flags );
-							}
-						} else {
-							$s .= '/>';
-						}
-						$out .= $s;
-					} else {
-						$params = [
-							'name' => new PPNode_DOM( $names->item( 0 ) ),
-							'attr' => $attrs->length > 0 ? new PPNode_DOM( $attrs->item( 0 ) ) : null,
-							'inner' => $inners->length > 0 ? new PPNode_DOM( $inners->item( 0 ) ) : null,
-							'close' => $closes->length > 0 ? new PPNode_DOM( $closes->item( 0 ) ) : null,
-						];
-						$out .= $this->parser->extensionSubstitution( $params, $this );
-					}
-				} elseif ( $contextNode->nodeName == 'h' ) {
-					# Heading
-					$s = $this->expand( $contextNode->childNodes, $flags );
-
-					# Insert a heading marker only for <h> children of <root>
-					# This is to stop extractSections from going over multiple tree levels
-					if ( $contextNode->parentNode->nodeName == 'root' && $this->parser->ot['html'] ) {
-						# Insert heading index marker
-						$headingIndex = $contextNode->getAttribute( 'i' );
-						$titleText = $this->title->getPrefixedDBkey();
-						$this->parser->mHeadings[] = [ $titleText, $headingIndex ];
-						$serial = count( $this->parser->mHeadings ) - 1;
-						$marker = Parser::MARKER_PREFIX . "-h-$serial-" . Parser::MARKER_SUFFIX;
-						$count = $contextNode->getAttribute( 'level' );
-						$s = substr( $s, 0, $count ) . $marker . substr( $s, $count );
-						$this->parser->mStripState->addGeneral( $marker, '' );
-					}
-					$out .= $s;
-				} else {
-					# Generic recursive expansion
-					$newIterator = $contextNode->childNodes;
-				}
-			} else {
-				throw new MWException( __METHOD__ . ': Invalid parameter type' );
-			}
-
-			if ( $newIterator !== false ) {
-				if ( $newIterator instanceof PPNode_DOM ) {
-					$newIterator = $newIterator->node;
-				}
-				$outStack[] = '';
-				$iteratorStack[] = $newIterator;
-				$indexStack[] = 0;
-			} elseif ( $iteratorStack[$level] === false ) {
-				// Return accumulated value to parent
-				// With tail recursion
-				while ( $iteratorStack[$level] === false && $level > 0 ) {
-					$outStack[$level - 1] .= $out;
-					array_pop( $outStack );
-					array_pop( $iteratorStack );
-					array_pop( $indexStack );
-					$level--;
-				}
-			}
-		}
-		--$expansionDepth;
-		return $outStack[0];
-	}
-
-	/**
-	 * @param string $sep
-	 * @param int $flags
-	 * @param string|PPNode_DOM|DOMDocument ...$args
-	 * @return string
-	 */
-	public function implodeWithFlags( $sep, $flags, ...$args ) {
-		$first = true;
-		$s = '';
-		foreach ( $args as $root ) {
-			if ( $root instanceof PPNode_DOM ) {
-				$root = $root->node;
-			}
-			if ( !is_array( $root ) && !( $root instanceof DOMNodeList ) ) {
-				$root = [ $root ];
-			}
-			foreach ( $root as $node ) {
-				if ( $first ) {
-					$first = false;
-				} else {
-					$s .= $sep;
-				}
-				$s .= $this->expand( $node, $flags );
-			}
-		}
-		return $s;
-	}
-
-	/**
-	 * Implode with no flags specified
-	 * This previously called implodeWithFlags but has now been inlined to reduce stack depth
-	 *
-	 * @param string $sep
-	 * @param string|PPNode_DOM|DOMDocument ...$args
-	 * @return string
-	 */
-	public function implode( $sep, ...$args ) {
-		$first = true;
-		$s = '';
-		foreach ( $args as $root ) {
-			if ( $root instanceof PPNode_DOM ) {
-				$root = $root->node;
-			}
-			if ( !is_array( $root ) && !( $root instanceof DOMNodeList ) ) {
-				$root = [ $root ];
-			}
-			foreach ( $root as $node ) {
-				if ( $first ) {
-					$first = false;
-				} else {
-					$s .= $sep;
-				}
-				$s .= $this->expand( $node );
-			}
-		}
-		return $s;
-	}
-
-	/**
-	 * Makes an object that, when expand()ed, will be the same as one obtained
-	 * with implode()
-	 *
-	 * @param string $sep
-	 * @param string|PPNode_DOM|DOMDocument ...$args
-	 * @return array
-	 */
-	public function virtualImplode( $sep, ...$args ) {
-		$out = [];
-		$first = true;
-
-		foreach ( $args as $root ) {
-			if ( $root instanceof PPNode_DOM ) {
-				$root = $root->node;
-			}
-			if ( !is_array( $root ) && !( $root instanceof DOMNodeList ) ) {
-				$root = [ $root ];
-			}
-			foreach ( $root as $node ) {
-				if ( $first ) {
-					$first = false;
-				} else {
-					$out[] = $sep;
-				}
-				$out[] = $node;
-			}
-		}
-		return $out;
-	}
-
-	/**
-	 * Virtual implode with brackets
-	 * @param string $start
-	 * @param string $sep
-	 * @param string $end
-	 * @param string|PPNode_DOM|DOMDocument ...$args
-	 * @return array
-	 */
-	public function virtualBracketedImplode( $start, $sep, $end, ...$args ) {
-		$out = [ $start ];
-		$first = true;
-
-		foreach ( $args as $root ) {
-			if ( $root instanceof PPNode_DOM ) {
-				$root = $root->node;
-			}
-			if ( !is_array( $root ) && !( $root instanceof DOMNodeList ) ) {
-				$root = [ $root ];
-			}
-			foreach ( $root as $node ) {
-				if ( $first ) {
-					$first = false;
-				} else {
-					$out[] = $sep;
-				}
-				$out[] = $node;
-			}
-		}
-		$out[] = $end;
-		return $out;
-	}
-
-	public function __toString() {
-		return 'frame{}';
-	}
-
-	public function getPDBK( $level = false ) {
-		if ( $level === false ) {
-			return $this->title->getPrefixedDBkey();
-		} else {
-			return $this->titleCache[$level] ?? false;
-		}
-	}
-
-	/**
-	 * @return array
-	 */
-	public function getArguments() {
-		return [];
-	}
-
-	/**
-	 * @return array
-	 */
-	public function getNumberedArguments() {
-		return [];
-	}
-
-	/**
-	 * @return array
-	 */
-	public function getNamedArguments() {
-		return [];
-	}
-
-	/**
-	 * Returns true if there are no arguments in this frame
-	 *
-	 * @return bool
-	 */
-	public function isEmpty() {
-		return true;
-	}
-
-	/**
-	 * @param int|string $name
-	 * @return bool Always false in this implementation.
-	 */
-	public function getArgument( $name ) {
-		return false;
-	}
-
-	/**
-	 * Returns true if the infinite loop check is OK, false if a loop is detected
-	 *
-	 * @param Title $title
-	 * @return bool
-	 */
-	public function loopCheck( $title ) {
-		return !isset( $this->loopCheckHash[$title->getPrefixedDBkey()] );
-	}
-
-	/**
-	 * Return true if the frame is a template frame
-	 *
-	 * @return bool
-	 */
-	public function isTemplate() {
-		return false;
-	}
-
-	/**
-	 * Get a title of frame
-	 *
-	 * @return Title
-	 */
-	public function getTitle() {
-		return $this->title;
-	}
-
-	/**
-	 * Set the volatile flag
-	 *
-	 * @param bool $flag
-	 */
-	public function setVolatile( $flag = true ) {
-		$this->volatile = $flag;
-	}
-
-	/**
-	 * Get the volatile flag
-	 *
-	 * @return bool
-	 */
-	public function isVolatile() {
-		return $this->volatile;
-	}
-
-	/**
-	 * Set the TTL
-	 *
-	 * @param int $ttl
-	 */
-	public function setTTL( $ttl ) {
-		if ( $ttl !== null && ( $this->ttl === null || $ttl < $this->ttl ) ) {
-			$this->ttl = $ttl;
-		}
-	}
-
-	/**
-	 * Get the TTL
-	 *
-	 * @return int|null
-	 */
-	public function getTTL() {
-		return $this->ttl;
-	}
-}
-
-/**
- * Expansion frame with template arguments
- * @ingroup Parser
- */
-// phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
-class PPTemplateFrame_DOM extends PPFrame_DOM {
-
-	public $numberedArgs, $namedArgs;
-
-	/**
-	 * @var PPFrame_DOM
-	 */
-	public $parent;
-	public $numberedExpansionCache, $namedExpansionCache;
-
-	/**
-	 * @param Preprocessor $preprocessor
-	 * @param bool|PPFrame_DOM $parent
-	 * @param array $numberedArgs
-	 * @param array $namedArgs
-	 * @param bool|Title $title
-	 */
-	public function __construct( $preprocessor, $parent = false, $numberedArgs = [],
-		$namedArgs = [], $title = false
-	) {
-		parent::__construct( $preprocessor );
-
-		$this->parent = $parent;
-		$this->numberedArgs = $numberedArgs;
-		$this->namedArgs = $namedArgs;
-		$this->title = $title;
-		$pdbk = $title ? $title->getPrefixedDBkey() : false;
-		$this->titleCache = $parent->titleCache;
-		$this->titleCache[] = $pdbk;
-		$this->loopCheckHash = /*clone*/ $parent->loopCheckHash;
-		if ( $pdbk !== false ) {
-			$this->loopCheckHash[$pdbk] = true;
-		}
-		$this->depth = $parent->depth + 1;
-		$this->numberedExpansionCache = $this->namedExpansionCache = [];
-	}
-
-	public function __toString() {
-		$s = 'tplframe{';
-		$first = true;
-		$args = $this->numberedArgs + $this->namedArgs;
-		foreach ( $args as $name => $value ) {
-			if ( $first ) {
-				$first = false;
-			} else {
-				$s .= ', ';
-			}
-			$s .= "\"$name\":\"" .
-				str_replace( '"', '\\"', $value->ownerDocument->saveXML( $value ) ) . '"';
-		}
-		$s .= '}';
-		return $s;
-	}
-
-	/**
-	 * @throws MWException
-	 * @param string|int $key
-	 * @param string|PPNode_DOM|DOMDocument $root
-	 * @param int $flags
-	 * @return string
-	 */
-	public function cachedExpand( $key, $root, $flags = 0 ) {
-		if ( isset( $this->parent->childExpansionCache[$key] ) ) {
-			return $this->parent->childExpansionCache[$key];
-		}
-		$retval = $this->expand( $root, $flags );
-		if ( !$this->isVolatile() ) {
-			$this->parent->childExpansionCache[$key] = $retval;
-		}
-		return $retval;
-	}
-
-	/**
-	 * Returns true if there are no arguments in this frame
-	 *
-	 * @return bool
-	 */
-	public function isEmpty() {
-		return !count( $this->numberedArgs ) && !count( $this->namedArgs );
-	}
-
-	public function getArguments() {
-		$arguments = [];
-		foreach ( array_merge(
-				array_keys( $this->numberedArgs ),
-				array_keys( $this->namedArgs ) ) as $key ) {
-			$arguments[$key] = $this->getArgument( $key );
-		}
-		return $arguments;
-	}
-
-	public function getNumberedArguments() {
-		$arguments = [];
-		foreach ( array_keys( $this->numberedArgs ) as $key ) {
-			$arguments[$key] = $this->getArgument( $key );
-		}
-		return $arguments;
-	}
-
-	public function getNamedArguments() {
-		$arguments = [];
-		foreach ( array_keys( $this->namedArgs ) as $key ) {
-			$arguments[$key] = $this->getArgument( $key );
-		}
-		return $arguments;
-	}
-
-	/**
-	 * @param int $index
-	 * @return string|bool
-	 */
-	public function getNumberedArgument( $index ) {
-		if ( !isset( $this->numberedArgs[$index] ) ) {
-			return false;
-		}
-		if ( !isset( $this->numberedExpansionCache[$index] ) ) {
-			# No trimming for unnamed arguments
-			$this->numberedExpansionCache[$index] = $this->parent->expand(
-				$this->numberedArgs[$index],
-				PPFrame::STRIP_COMMENTS
-			);
-		}
-		return $this->numberedExpansionCache[$index];
-	}
-
-	/**
-	 * @param string $name
-	 * @return string|bool
-	 */
-	public function getNamedArgument( $name ) {
-		if ( !isset( $this->namedArgs[$name] ) ) {
-			return false;
-		}
-		if ( !isset( $this->namedExpansionCache[$name] ) ) {
-			# Trim named arguments post-expand, for backwards compatibility
-			$this->namedExpansionCache[$name] = trim(
-				$this->parent->expand( $this->namedArgs[$name], PPFrame::STRIP_COMMENTS ) );
-		}
-		return $this->namedExpansionCache[$name];
-	}
-
-	/**
-	 * @param int|string $name
-	 * @return string|bool
-	 */
-	public function getArgument( $name ) {
-		$text = $this->getNumberedArgument( $name );
-		if ( $text === false ) {
-			$text = $this->getNamedArgument( $name );
-		}
-		return $text;
-	}
-
-	/**
-	 * Return true if the frame is a template frame
-	 *
-	 * @return bool
-	 */
-	public function isTemplate() {
-		return true;
-	}
-
-	public function setVolatile( $flag = true ) {
-		parent::setVolatile( $flag );
-		$this->parent->setVolatile( $flag );
-	}
-
-	public function setTTL( $ttl ) {
-		parent::setTTL( $ttl );
-		$this->parent->setTTL( $ttl );
-	}
-}
-
-/**
- * Expansion frame with custom arguments
- * @ingroup Parser
- */
-// phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
-class PPCustomFrame_DOM extends PPFrame_DOM {
-
-	public $args;
-
-	public function __construct( $preprocessor, $args ) {
-		parent::__construct( $preprocessor );
-		$this->args = $args;
-	}
-
-	public function __toString() {
-		$s = 'cstmframe{';
-		$first = true;
-		foreach ( $this->args as $name => $value ) {
-			if ( $first ) {
-				$first = false;
-			} else {
-				$s .= ', ';
-			}
-			$s .= "\"$name\":\"" .
-				str_replace( '"', '\\"', $value->__toString() ) . '"';
-		}
-		$s .= '}';
-		return $s;
-	}
-
-	/**
-	 * @return bool
-	 */
-	public function isEmpty() {
-		return !count( $this->args );
-	}
-
-	/**
-	 * @param int|string $index
-	 * @return string|bool
-	 */
-	public function getArgument( $index ) {
-		return $this->args[$index] ?? false;
-	}
-
-	public function getArguments() {
-		return $this->args;
-	}
-}
-
-/**
- * @ingroup Parser
- */
-// phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
-class PPNode_DOM implements PPNode {
-
-	/**
-	 * @var DOMElement
-	 */
-	public $node;
-	public $xpath;
-
-	public function __construct( $node, $xpath = false ) {
-		$this->node = $node;
-	}
-
-	/**
-	 * @return DOMXPath
-	 */
-	public function getXPath() {
-		if ( $this->xpath === null ) {
-			$this->xpath = new DOMXPath( $this->node->ownerDocument );
-		}
-		return $this->xpath;
-	}
-
-	public function __toString() {
-		if ( $this->node instanceof DOMNodeList ) {
-			$s = '';
-			foreach ( $this->node as $node ) {
-				$s .= $node->ownerDocument->saveXML( $node );
-			}
-		} else {
-			$s = $this->node->ownerDocument->saveXML( $this->node );
-		}
-		return $s;
-	}
-
-	/**
-	 * @return bool|PPNode_DOM
-	 */
-	public function getChildren() {
-		return $this->node->childNodes ? new self( $this->node->childNodes ) : false;
-	}
-
-	/**
-	 * @return bool|PPNode_DOM
-	 */
-	public function getFirstChild() {
-		return $this->node->firstChild ? new self( $this->node->firstChild ) : false;
-	}
-
-	/**
-	 * @return bool|PPNode_DOM
-	 */
-	public function getNextSibling() {
-		return $this->node->nextSibling ? new self( $this->node->nextSibling ) : false;
-	}
-
-	/**
-	 * @param string $type
-	 *
-	 * @return bool|PPNode_DOM
-	 */
-	public function getChildrenOfType( $type ) {
-		return new self( $this->getXPath()->query( $type, $this->node ) );
-	}
-
-	/**
-	 * @return int
-	 */
-	public function getLength() {
-		if ( $this->node instanceof DOMNodeList ) {
-			return $this->node->length;
-		} else {
-			return false;
-		}
-	}
-
-	/**
-	 * @param int $i
-	 * @return bool|PPNode_DOM
-	 */
-	public function item( $i ) {
-		$item = $this->node->item( $i );
-		return $item ? new self( $item ) : false;
-	}
-
-	/**
-	 * @return string
-	 */
-	public function getName() {
-		if ( $this->node instanceof DOMNodeList ) {
-			return '#nodelist';
-		} else {
-			return $this->node->nodeName;
-		}
-	}
-
-	/**
-	 * Split a "<part>" node into an associative array containing:
-	 *  - name          PPNode name
-	 *  - index         String index
-	 *  - value         PPNode value
-	 *
-	 * @throws MWException
-	 * @return array
-	 */
-	public function splitArg() {
-		$xpath = $this->getXPath();
-		$names = $xpath->query( 'name', $this->node );
-		$values = $xpath->query( 'value', $this->node );
-		if ( !$names->length || !$values->length ) {
-			throw new MWException( 'Invalid brace node passed to ' . __METHOD__ );
-		}
-		$name = $names->item( 0 );
-		$index = $name->getAttribute( 'index' );
-		return [
-			'name' => new self( $name ),
-			'index' => $index,
-			'value' => new self( $values->item( 0 ) ) ];
-	}
-
-	/**
-	 * Split an "<ext>" node into an associative array containing name, attr, inner and close
-	 * All values in the resulting array are PPNodes. Inner and close are optional.
-	 *
-	 * @throws MWException
-	 * @return array
-	 */
-	public function splitExt() {
-		$xpath = $this->getXPath();
-		$names = $xpath->query( 'name', $this->node );
-		$attrs = $xpath->query( 'attr', $this->node );
-		$inners = $xpath->query( 'inner', $this->node );
-		$closes = $xpath->query( 'close', $this->node );
-		if ( !$names->length || !$attrs->length ) {
-			throw new MWException( 'Invalid ext node passed to ' . __METHOD__ );
-		}
-		$parts = [
-			'name' => new self( $names->item( 0 ) ),
-			'attr' => new self( $attrs->item( 0 ) ) ];
-		if ( $inners->length ) {
-			$parts['inner'] = new self( $inners->item( 0 ) );
-		}
-		if ( $closes->length ) {
-			$parts['close'] = new self( $closes->item( 0 ) );
-		}
-		return $parts;
-	}
-
-	/**
-	 * Split a "<h>" node
-	 * @throws MWException
-	 * @return array
-	 */
-	public function splitHeading() {
-		if ( $this->getName() !== 'h' ) {
-			throw new MWException( 'Invalid h node passed to ' . __METHOD__ );
-		}
-		return [
-			'i' => $this->node->getAttribute( 'i' ),
-			'level' => $this->node->getAttribute( 'level' ),
-			'contents' => $this->getChildren()
-		];
-	}
-}
diff --git a/includes/parser/Preprocessor_Hash.php b/includes/parser/Preprocessor_Hash.php
index a845047398..66f081fe77 100644
--- a/includes/parser/Preprocessor_Hash.php
+++ b/includes/parser/Preprocessor_Hash.php
@@ -795,1459 +795,3 @@ class Preprocessor_Hash extends Preprocessor {
 		}
 	}
 }
-
-/**
- * Stack class to help Preprocessor::preprocessToObj()
- * @ingroup Parser
- */
-// phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
-class PPDStack_Hash extends PPDStack {
-
-	public function __construct() {
-		$this->elementClass = PPDStackElement_Hash::class;
-		parent::__construct();
-		$this->rootAccum = [];
-	}
-}
-
-/**
- * @ingroup Parser
- */
-// phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
-class PPDStackElement_Hash extends PPDStackElement {
-
-	public function __construct( $data = [] ) {
-		$this->partClass = PPDPart_Hash::class;
-		parent::__construct( $data );
-	}
-
-	/**
-	 * Get the accumulator that would result if the close is not found.
-	 *
-	 * @param int|bool $openingCount
-	 * @return array
-	 */
-	public function breakSyntax( $openingCount = false ) {
-		if ( $this->open == "\n" ) {
-			$accum = array_merge( [ $this->savedPrefix ], $this->parts[0]->out );
-		} else {
-			if ( $openingCount === false ) {
-				$openingCount = $this->count;
-			}
-			$s = substr( $this->open, 0, -1 );
-			$s .= str_repeat(
-				substr( $this->open, -1 ),
-				$openingCount - strlen( $s )
-			);
-			$accum = [ $this->savedPrefix . $s ];
-			$lastIndex = 0;
-			$first = true;
-			foreach ( $this->parts as $part ) {
-				if ( $first ) {
-					$first = false;
-				} elseif ( is_string( $accum[$lastIndex] ) ) {
-					$accum[$lastIndex] .= '|';
-				} else {
-					$accum[++$lastIndex] = '|';
-				}
-				foreach ( $part->out as $node ) {
-					if ( is_string( $node ) && is_string( $accum[$lastIndex] ) ) {
-						$accum[$lastIndex] .= $node;
-					} else {
-						$accum[++$lastIndex] = $node;
-					}
-				}
-			}
-		}
-		return $accum;
-	}
-}
-
-/**
- * @ingroup Parser
- */
-// phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
-class PPDPart_Hash extends PPDPart {
-
-	public function __construct( $out = '' ) {
-		if ( $out !== '' ) {
-			$accum = [ $out ];
-		} else {
-			$accum = [];
-		}
-		parent::__construct( $accum );
-	}
-}
-
-/**
- * An expansion frame, used as a context to expand the result of preprocessToObj()
- * @ingroup Parser
- */
-// phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
-class PPFrame_Hash implements PPFrame {
-
-	/**
-	 * @var Parser
-	 */
-	public $parser;
-
-	/**
-	 * @var Preprocessor
-	 */
-	public $preprocessor;
-
-	/**
-	 * @var Title
-	 */
-	public $title;
-	public $titleCache;
-
-	/**
-	 * Hashtable listing templates which are disallowed for expansion in this frame,
-	 * having been encountered previously in parent frames.
-	 */
-	public $loopCheckHash;
-
-	/**
-	 * Recursion depth of this frame, top = 0
-	 * Note that this is NOT the same as expansion depth in expand()
-	 */
-	public $depth;
-
-	private $volatile = false;
-	private $ttl = null;
-
-	/**
-	 * @var array
-	 */
-	protected $childExpansionCache;
-
-	/**
-	 * Construct a new preprocessor frame.
-	 * @param Preprocessor $preprocessor The parent preprocessor
-	 */
-	public function __construct( $preprocessor ) {
-		$this->preprocessor = $preprocessor;
-		$this->parser = $preprocessor->parser;
-		$this->title = $this->parser->mTitle;
-		$this->titleCache = [ $this->title ? $this->title->getPrefixedDBkey() : false ];
-		$this->loopCheckHash = [];
-		$this->depth = 0;
-		$this->childExpansionCache = [];
-	}
-
-	/**
-	 * Create a new child frame
-	 * $args is optionally a multi-root PPNode or array containing the template arguments
-	 *
-	 * @param array|bool|PPNode_Hash_Array $args
-	 * @param Title|bool $title
-	 * @param int $indexOffset
-	 * @throws MWException
-	 * @return PPTemplateFrame_Hash
-	 */
-	public function newChild( $args = false, $title = false, $indexOffset = 0 ) {
-		$namedArgs = [];
-		$numberedArgs = [];
-		if ( $title === false ) {
-			$title = $this->title;
-		}
-		if ( $args !== false ) {
-			if ( $args instanceof PPNode_Hash_Array ) {
-				$args = $args->value;
-			} elseif ( !is_array( $args ) ) {
-				throw new MWException( __METHOD__ . ': $args must be array or PPNode_Hash_Array' );
-			}
-			foreach ( $args as $arg ) {
-				$bits = $arg->splitArg();
-				if ( $bits['index'] !== '' ) {
-					// Numbered parameter
-					$index = $bits['index'] - $indexOffset;
-					if ( isset( $namedArgs[$index] ) || isset( $numberedArgs[$index] ) ) {
-						$this->parser->getOutput()->addWarning( wfMessage( 'duplicate-args-warning',
-							wfEscapeWikiText( $this->title ),
-							wfEscapeWikiText( $title ),
-							wfEscapeWikiText( $index ) )->text() );
-						$this->parser->addTrackingCategory( 'duplicate-args-category' );
-					}
-					$numberedArgs[$index] = $bits['value'];
-					unset( $namedArgs[$index] );
-				} else {
-					// Named parameter
-					$name = trim( $this->expand( $bits['name'], PPFrame::STRIP_COMMENTS ) );
-					if ( isset( $namedArgs[$name] ) || isset( $numberedArgs[$name] ) ) {
-						$this->parser->getOutput()->addWarning( wfMessage( 'duplicate-args-warning',
-							wfEscapeWikiText( $this->title ),
-							wfEscapeWikiText( $title ),
-							wfEscapeWikiText( $name ) )->text() );
-						$this->parser->addTrackingCategory( 'duplicate-args-category' );
-					}
-					$namedArgs[$name] = $bits['value'];
-					unset( $numberedArgs[$name] );
-				}
-			}
-		}
-		return new PPTemplateFrame_Hash( $this->preprocessor, $this, $numberedArgs, $namedArgs, $title );
-	}
-
-	/**
-	 * @throws MWException
-	 * @param string|int $key
-	 * @param string|PPNode $root
-	 * @param int $flags
-	 * @return string
-	 */
-	public function cachedExpand( $key, $root, $flags = 0 ) {
-		// we don't have a parent, so we don't have a cache
-		return $this->expand( $root, $flags );
-	}
-
-	/**
-	 * @throws MWException
-	 * @param string|PPNode $root
-	 * @param int $flags
-	 * @return string
-	 */
-	public function expand( $root, $flags = 0 ) {
-		static $expansionDepth = 0;
-		if ( is_string( $root ) ) {
-			return $root;
-		}
-
-		if ( ++$this->parser->mPPNodeCount > $this->parser->mOptions->getMaxPPNodeCount() ) {
-			$this->parser->limitationWarn( 'node-count-exceeded',
-					$this->parser->mPPNodeCount,
-					$this->parser->mOptions->getMaxPPNodeCount()
-			);
-			return '<span class="error">Node-count limit exceeded</span>';
-		}
-		if ( $expansionDepth > $this->parser->mOptions->getMaxPPExpandDepth() ) {
-			$this->parser->limitationWarn( 'expansion-depth-exceeded',
-					$expansionDepth,
-					$this->parser->mOptions->getMaxPPExpandDepth()
-			);
-			return '<span class="error">Expansion depth limit exceeded</span>';
-		}
-		++$expansionDepth;
-		if ( $expansionDepth > $this->parser->mHighestExpansionDepth ) {
-			$this->parser->mHighestExpansionDepth = $expansionDepth;
-		}
-
-		$outStack = [ '', '' ];
-		$iteratorStack = [ false, $root ];
-		$indexStack = [ 0, 0 ];
-
-		while ( count( $iteratorStack ) > 1 ) {
-			$level = count( $outStack ) - 1;
-			$iteratorNode =& $iteratorStack[$level];
-			$out =& $outStack[$level];
-			$index =& $indexStack[$level];
-
-			if ( is_array( $iteratorNode ) ) {
-				if ( $index >= count( $iteratorNode ) ) {
-					// All done with this iterator
-					$iteratorStack[$level] = false;
-					$contextNode = false;
-				} else {
-					$contextNode = $iteratorNode[$index];
-					$index++;
-				}
-			} elseif ( $iteratorNode instanceof PPNode_Hash_Array ) {
-				if ( $index >= $iteratorNode->getLength() ) {
-					// All done with this iterator
-					$iteratorStack[$level] = false;
-					$contextNode = false;
-				} else {
-					$contextNode = $iteratorNode->item( $index );
-					$index++;
-				}
-			} else {
-				// Copy to $contextNode and then delete from iterator stack,
-				// because this is not an iterator but we do have to execute it once
-				$contextNode = $iteratorStack[$level];
-				$iteratorStack[$level] = false;
-			}
-
-			$newIterator = false;
-			$contextName = false;
-			$contextChildren = false;
-
-			if ( $contextNode === false ) {
-				// nothing to do
-			} elseif ( is_string( $contextNode ) ) {
-				$out .= $contextNode;
-			} elseif ( $contextNode instanceof PPNode_Hash_Array ) {
-				$newIterator = $contextNode;
-			} elseif ( $contextNode instanceof PPNode_Hash_Attr ) {
-				// No output
-			} elseif ( $contextNode instanceof PPNode_Hash_Text ) {
-				$out .= $contextNode->value;
-			} elseif ( $contextNode instanceof PPNode_Hash_Tree ) {
-				$contextName = $contextNode->name;
-				$contextChildren = $contextNode->getRawChildren();
-			} elseif ( is_array( $contextNode ) ) {
-				// Node descriptor array
-				if ( count( $contextNode ) !== 2 ) {
-					throw new MWException( __METHOD__ .
-						': found an array where a node descriptor should be' );
-				}
-				list( $contextName, $contextChildren ) = $contextNode;
-			} else {
-				throw new MWException( __METHOD__ . ': Invalid parameter type' );
-			}
-
-			// Handle node descriptor array or tree object
-			if ( $contextName === false ) {
-				// Not a node, already handled above
-			} elseif ( $contextName[0] === '@' ) {
-				// Attribute: no output
-			} elseif ( $contextName === 'template' ) {
-				# Double-brace expansion
-				$bits = PPNode_Hash_Tree::splitRawTemplate( $contextChildren );
-				if ( $flags & PPFrame::NO_TEMPLATES ) {
-					$newIterator = $this->virtualBracketedImplode(
-						'{{', '|', '}}',
-						$bits['title'],
-						$bits['parts']
-					);
-				} else {
-					$ret = $this->parser->braceSubstitution( $bits, $this );
-					if ( isset( $ret['object'] ) ) {
-						$newIterator = $ret['object'];
-					} else {
-						$out .= $ret['text'];
-					}
-				}
-			} elseif ( $contextName === 'tplarg' ) {
-				# Triple-brace expansion
-				$bits = PPNode_Hash_Tree::splitRawTemplate( $contextChildren );
-				if ( $flags & PPFrame::NO_ARGS ) {
-					$newIterator = $this->virtualBracketedImplode(
-						'{{{', '|', '}}}',
-						$bits['title'],
-						$bits['parts']
-					);
-				} else {
-					$ret = $this->parser->argSubstitution( $bits, $this );
-					if ( isset( $ret['object'] ) ) {
-						$newIterator = $ret['object'];
-					} else {
-						$out .= $ret['text'];
-					}
-				}
-			} elseif ( $contextName === 'comment' ) {
-				# HTML-style comment
-				# Remove it in HTML, pre+remove and STRIP_COMMENTS modes
-				# Not in RECOVER_COMMENTS mode (msgnw) though.
-				if ( ( $this->parser->ot['html']
-					|| ( $this->parser->ot['pre'] && $this->parser->mOptions->getRemoveComments() )
-					|| ( $flags & PPFrame::STRIP_COMMENTS )
-					) && !( $flags & PPFrame::RECOVER_COMMENTS )
-				) {
-					$out .= '';
-				} elseif ( $this->parser->ot['wiki'] && !( $flags & PPFrame::RECOVER_COMMENTS ) ) {
-					# Add a strip marker in PST mode so that pstPass2() can
-					# run some old-fashioned regexes on the result.
-					# Not in RECOVER_COMMENTS mode (extractSections) though.
-					$out .= $this->parser->insertStripItem( $contextChildren[0] );
-				} else {
-					# Recover the literal comment in RECOVER_COMMENTS and pre+no-remove
-					$out .= $contextChildren[0];
-				}
-			} elseif ( $contextName === 'ignore' ) {
-				# Output suppression used by <includeonly> etc.
-				# OT_WIKI will only respect <ignore> in substed templates.
-				# The other output types respect it unless NO_IGNORE is set.
-				# extractSections() sets NO_IGNORE and so never respects it.
-				if ( ( !isset( $this->parent ) && $this->parser->ot['wiki'] )
-					|| ( $flags & PPFrame::NO_IGNORE )
-				) {
-					$out .= $contextChildren[0];
-				} else {
-					// $out .= '';
-				}
-			} elseif ( $contextName === 'ext' ) {
-				# Extension tag
-				$bits = PPNode_Hash_Tree::splitRawExt( $contextChildren ) +
-					[ 'attr' => null, 'inner' => null, 'close' => null ];
-				if ( $flags & PPFrame::NO_TAGS ) {
-					$s = '<' . $bits['name']->getFirstChild()->value;
-					if ( $bits['attr'] ) {
-						$s .= $bits['attr']->getFirstChild()->value;
-					}
-					if ( $bits['inner'] ) {
-						$s .= '>' . $bits['inner']->getFirstChild()->value;
-						if ( $bits['close'] ) {
-							$s .= $bits['close']->getFirstChild()->value;
-						}
-					} else {
-						$s .= '/>';
-					}
-					$out .= $s;
-				} else {
-					$out .= $this->parser->extensionSubstitution( $bits, $this );
-				}
-			} elseif ( $contextName === 'h' ) {
-				# Heading
-				if ( $this->parser->ot['html'] ) {
-					# Expand immediately and insert heading index marker
-					$s = $this->expand( $contextChildren, $flags );
-					$bits = PPNode_Hash_Tree::splitRawHeading( $contextChildren );
-					$titleText = $this->title->getPrefixedDBkey();
-					$this->parser->mHeadings[] = [ $titleText, $bits['i'] ];
-					$serial = count( $this->parser->mHeadings ) - 1;
-					$marker = Parser::MARKER_PREFIX . "-h-$serial-" . Parser::MARKER_SUFFIX;
-					$s = substr( $s, 0, $bits['level'] ) . $marker . substr( $s, $bits['level'] );
-					$this->parser->mStripState->addGeneral( $marker, '' );
-					$out .= $s;
-				} else {
-					# Expand in virtual stack
-					$newIterator = $contextChildren;
-				}
-			} else {
-				# Generic recursive expansion
-				$newIterator = $contextChildren;
-			}
-
-			if ( $newIterator !== false ) {
-				$outStack[] = '';
-				$iteratorStack[] = $newIterator;
-				$indexStack[] = 0;
-			} elseif ( $iteratorStack[$level] === false ) {
-				// Return accumulated value to parent
-				// With tail recursion
-				while ( $iteratorStack[$level] === false && $level > 0 ) {
-					$outStack[$level - 1] .= $out;
-					array_pop( $outStack );
-					array_pop( $iteratorStack );
-					array_pop( $indexStack );
-					$level--;
-				}
-			}
-		}
-		--$expansionDepth;
-		return $outStack[0];
-	}
-
-	/**
-	 * @param string $sep
-	 * @param int $flags
-	 * @param string|PPNode ...$args
-	 * @return string
-	 */
-	public function implodeWithFlags( $sep, $flags, ...$args ) {
-		$first = true;
-		$s = '';
-		foreach ( $args as $root ) {
-			if ( $root instanceof PPNode_Hash_Array ) {
-				$root = $root->value;
-			}
-			if ( !is_array( $root ) ) {
-				$root = [ $root ];
-			}
-			foreach ( $root as $node ) {
-				if ( $first ) {
-					$first = false;
-				} else {
-					$s .= $sep;
-				}
-				$s .= $this->expand( $node, $flags );
-			}
-		}
-		return $s;
-	}
-
-	/**
-	 * Implode with no flags specified
-	 * This previously called implodeWithFlags but has now been inlined to reduce stack depth
-	 * @param string $sep
-	 * @param string|PPNode ...$args
-	 * @return string
-	 */
-	public function implode( $sep, ...$args ) {
-		$first = true;
-		$s = '';
-		foreach ( $args as $root ) {
-			if ( $root instanceof PPNode_Hash_Array ) {
-				$root = $root->value;
-			}
-			if ( !is_array( $root ) ) {
-				$root = [ $root ];
-			}
-			foreach ( $root as $node ) {
-				if ( $first ) {
-					$first = false;
-				} else {
-					$s .= $sep;
-				}
-				$s .= $this->expand( $node );
-			}
-		}
-		return $s;
-	}
-
-	/**
-	 * Makes an object that, when expand()ed, will be the same as one obtained
-	 * with implode()
-	 *
-	 * @param string $sep
-	 * @param string|PPNode ...$args
-	 * @return PPNode_Hash_Array
-	 */
-	public function virtualImplode( $sep, ...$args ) {
-		$out = [];
-		$first = true;
-
-		foreach ( $args as $root ) {
-			if ( $root instanceof PPNode_Hash_Array ) {
-				$root = $root->value;
-			}
-			if ( !is_array( $root ) ) {
-				$root = [ $root ];
-			}
-			foreach ( $root as $node ) {
-				if ( $first ) {
-					$first = false;
-				} else {
-					$out[] = $sep;
-				}
-				$out[] = $node;
-			}
-		}
-		return new PPNode_Hash_Array( $out );
-	}
-
-	/**
-	 * Virtual implode with brackets
-	 *
-	 * @param string $start
-	 * @param string $sep
-	 * @param string $end
-	 * @param string|PPNode ...$args
-	 * @return PPNode_Hash_Array
-	 */
-	public function virtualBracketedImplode( $start, $sep, $end, ...$args ) {
-		$out = [ $start ];
-		$first = true;
-
-		foreach ( $args as $root ) {
-			if ( $root instanceof PPNode_Hash_Array ) {
-				$root = $root->value;
-			}
-			if ( !is_array( $root ) ) {
-				$root = [ $root ];
-			}
-			foreach ( $root as $node ) {
-				if ( $first ) {
-					$first = false;
-				} else {
-					$out[] = $sep;
-				}
-				$out[] = $node;
-			}
-		}
-		$out[] = $end;
-		return new PPNode_Hash_Array( $out );
-	}
-
-	public function __toString() {
-		return 'frame{}';
-	}
-
-	/**
-	 * @param bool $level
-	 * @return array|bool|string
-	 */
-	public function getPDBK( $level = false ) {
-		if ( $level === false ) {
-			return $this->title->getPrefixedDBkey();
-		} else {
-			return $this->titleCache[$level] ?? false;
-		}
-	}
-
-	/**
-	 * @return array
-	 */
-	public function getArguments() {
-		return [];
-	}
-
-	/**
-	 * @return array
-	 */
-	public function getNumberedArguments() {
-		return [];
-	}
-
-	/**
-	 * @return array
-	 */
-	public function getNamedArguments() {
-		return [];
-	}
-
-	/**
-	 * Returns true if there are no arguments in this frame
-	 *
-	 * @return bool
-	 */
-	public function isEmpty() {
-		return true;
-	}
-
-	/**
-	 * @param int|string $name
-	 * @return bool Always false in this implementation.
-	 */
-	public function getArgument( $name ) {
-		return false;
-	}
-
-	/**
-	 * Returns true if the infinite loop check is OK, false if a loop is detected
-	 *
-	 * @param Title $title
-	 *
-	 * @return bool
-	 */
-	public function loopCheck( $title ) {
-		return !isset( $this->loopCheckHash[$title->getPrefixedDBkey()] );
-	}
-
-	/**
-	 * Return true if the frame is a template frame
-	 *
-	 * @return bool
-	 */
-	public function isTemplate() {
-		return false;
-	}
-
-	/**
-	 * Get a title of frame
-	 *
-	 * @return Title
-	 */
-	public function getTitle() {
-		return $this->title;
-	}
-
-	/**
-	 * Set the volatile flag
-	 *
-	 * @param bool $flag
-	 */
-	public function setVolatile( $flag = true ) {
-		$this->volatile = $flag;
-	}
-
-	/**
-	 * Get the volatile flag
-	 *
-	 * @return bool
-	 */
-	public function isVolatile() {
-		return $this->volatile;
-	}
-
-	/**
-	 * Set the TTL
-	 *
-	 * @param int $ttl
-	 */
-	public function setTTL( $ttl ) {
-		if ( $ttl !== null && ( $this->ttl === null || $ttl < $this->ttl ) ) {
-			$this->ttl = $ttl;
-		}
-	}
-
-	/**
-	 * Get the TTL
-	 *
-	 * @return int|null
-	 */
-	public function getTTL() {
-		return $this->ttl;
-	}
-}
-
-/**
- * Expansion frame with template arguments
- * @ingroup Parser
- */
-// phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
-class PPTemplateFrame_Hash extends PPFrame_Hash {
-
-	public $numberedArgs, $namedArgs, $parent;
-	public $numberedExpansionCache, $namedExpansionCache;
-
-	/**
-	 * @param Preprocessor $preprocessor
-	 * @param bool|PPFrame $parent
-	 * @param array $numberedArgs
-	 * @param array $namedArgs
-	 * @param bool|Title $title
-	 */
-	public function __construct( $preprocessor, $parent = false, $numberedArgs = [],
-		$namedArgs = [], $title = false
-	) {
-		parent::__construct( $preprocessor );
-
-		$this->parent = $parent;
-		$this->numberedArgs = $numberedArgs;
-		$this->namedArgs = $namedArgs;
-		$this->title = $title;
-		$pdbk = $title ? $title->getPrefixedDBkey() : false;
-		$this->titleCache = $parent->titleCache;
-		$this->titleCache[] = $pdbk;
-		$this->loopCheckHash = /*clone*/ $parent->loopCheckHash;
-		if ( $pdbk !== false ) {
-			$this->loopCheckHash[$pdbk] = true;
-		}
-		$this->depth = $parent->depth + 1;
-		$this->numberedExpansionCache = $this->namedExpansionCache = [];
-	}
-
-	public function __toString() {
-		$s = 'tplframe{';
-		$first = true;
-		$args = $this->numberedArgs + $this->namedArgs;
-		foreach ( $args as $name => $value ) {
-			if ( $first ) {
-				$first = false;
-			} else {
-				$s .= ', ';
-			}
-			$s .= "\"$name\":\"" .
-				str_replace( '"', '\\"', $value->__toString() ) . '"';
-		}
-		$s .= '}';
-		return $s;
-	}
-
-	/**
-	 * @throws MWException
-	 * @param string|int $key
-	 * @param string|PPNode $root
-	 * @param int $flags
-	 * @return string
-	 */
-	public function cachedExpand( $key, $root, $flags = 0 ) {
-		if ( isset( $this->parent->childExpansionCache[$key] ) ) {
-			return $this->parent->childExpansionCache[$key];
-		}
-		$retval = $this->expand( $root, $flags );
-		if ( !$this->isVolatile() ) {
-			$this->parent->childExpansionCache[$key] = $retval;
-		}
-		return $retval;
-	}
-
-	/**
-	 * Returns true if there are no arguments in this frame
-	 *
-	 * @return bool
-	 */
-	public function isEmpty() {
-		return !count( $this->numberedArgs ) && !count( $this->namedArgs );
-	}
-
-	/**
-	 * @return array
-	 */
-	public function getArguments() {
-		$arguments = [];
-		foreach ( array_merge(
-				array_keys( $this->numberedArgs ),
-				array_keys( $this->namedArgs ) ) as $key ) {
-			$arguments[$key] = $this->getArgument( $key );
-		}
-		return $arguments;
-	}
-
-	/**
-	 * @return array
-	 */
-	public function getNumberedArguments() {
-		$arguments = [];
-		foreach ( array_keys( $this->numberedArgs ) as $key ) {
-			$arguments[$key] = $this->getArgument( $key );
-		}
-		return $arguments;
-	}
-
-	/**
-	 * @return array
-	 */
-	public function getNamedArguments() {
-		$arguments = [];
-		foreach ( array_keys( $this->namedArgs ) as $key ) {
-			$arguments[$key] = $this->getArgument( $key );
-		}
-		return $arguments;
-	}
-
-	/**
-	 * @param int $index
-	 * @return string|bool
-	 */
-	public function getNumberedArgument( $index ) {
-		if ( !isset( $this->numberedArgs[$index] ) ) {
-			return false;
-		}
-		if ( !isset( $this->numberedExpansionCache[$index] ) ) {
-			# No trimming for unnamed arguments
-			$this->numberedExpansionCache[$index] = $this->parent->expand(
-				$this->numberedArgs[$index],
-				PPFrame::STRIP_COMMENTS
-			);
-		}
-		return $this->numberedExpansionCache[$index];
-	}
-
-	/**
-	 * @param string $name
-	 * @return string|bool
-	 */
-	public function getNamedArgument( $name ) {
-		if ( !isset( $this->namedArgs[$name] ) ) {
-			return false;
-		}
-		if ( !isset( $this->namedExpansionCache[$name] ) ) {
-			# Trim named arguments post-expand, for backwards compatibility
-			$this->namedExpansionCache[$name] = trim(
-				$this->parent->expand( $this->namedArgs[$name], PPFrame::STRIP_COMMENTS ) );
-		}
-		return $this->namedExpansionCache[$name];
-	}
-
-	/**
-	 * @param int|string $name
-	 * @return string|bool
-	 */
-	public function getArgument( $name ) {
-		$text = $this->getNumberedArgument( $name );
-		if ( $text === false ) {
-			$text = $this->getNamedArgument( $name );
-		}
-		return $text;
-	}
-
-	/**
-	 * Return true if the frame is a template frame
-	 *
-	 * @return bool
-	 */
-	public function isTemplate() {
-		return true;
-	}
-
-	public function setVolatile( $flag = true ) {
-		parent::setVolatile( $flag );
-		$this->parent->setVolatile( $flag );
-	}
-
-	public function setTTL( $ttl ) {
-		parent::setTTL( $ttl );
-		$this->parent->setTTL( $ttl );
-	}
-}
-
-/**
- * Expansion frame with custom arguments
- * @ingroup Parser
- */
-// phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
-class PPCustomFrame_Hash extends PPFrame_Hash {
-
-	public $args;
-
-	public function __construct( $preprocessor, $args ) {
-		parent::__construct( $preprocessor );
-		$this->args = $args;
-	}
-
-	public function __toString() {
-		$s = 'cstmframe{';
-		$first = true;
-		foreach ( $this->args as $name => $value ) {
-			if ( $first ) {
-				$first = false;
-			} else {
-				$s .= ', ';
-			}
-			$s .= "\"$name\":\"" .
-				str_replace( '"', '\\"', $value->__toString() ) . '"';
-		}
-		$s .= '}';
-		return $s;
-	}
-
-	/**
-	 * @return bool
-	 */
-	public function isEmpty() {
-		return !count( $this->args );
-	}
-
-	/**
-	 * @param int|string $index
-	 * @return string|bool
-	 */
-	public function getArgument( $index ) {
-		return $this->args[$index] ?? false;
-	}
-
-	public function getArguments() {
-		return $this->args;
-	}
-}
-
-/**
- * @ingroup Parser
- */
-// phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
-class PPNode_Hash_Tree implements PPNode {
-
-	public $name;
-
-	/**
-	 * The store array for children of this node. It is "raw" in the sense that
-	 * nodes are two-element arrays ("descriptors") rather than PPNode_Hash_*
-	 * objects.
-	 */
-	private $rawChildren;
-
-	/**
-	 * The store array for the siblings of this node, including this node itself.
-	 */
-	private $store;
-
-	/**
-	 * The index into $this->store which contains the descriptor of this node.
-	 */
-	private $index;
-
-	/**
-	 * The offset of the name within descriptors, used in some places for
-	 * readability.
-	 */
-	const NAME = 0;
-
-	/**
-	 * The offset of the child list within descriptors, used in some places for
-	 * readability.
-	 */
-	const CHILDREN = 1;
-
-	/**
-	 * Construct an object using the data from $store[$index]. The rest of the
-	 * store array can be accessed via getNextSibling().
-	 *
-	 * @param array $store
-	 * @param int $index
-	 */
-	public function __construct( array $store, $index ) {
-		$this->store = $store;
-		$this->index = $index;
-		list( $this->name, $this->rawChildren ) = $this->store[$index];
-	}
-
-	/**
-	 * Construct an appropriate PPNode_Hash_* object with a class that depends
-	 * on what is at the relevant store index.
-	 *
-	 * @param array $store
-	 * @param int $index
-	 * @return PPNode_Hash_Tree|PPNode_Hash_Attr|PPNode_Hash_Text|false
-	 * @throws MWException
-	 */
-	public static function factory( array $store, $index ) {
-		if ( !isset( $store[$index] ) ) {
-			return false;
-		}
-
-		$descriptor = $store[$index];
-		if ( is_string( $descriptor ) ) {
-			$class = PPNode_Hash_Text::class;
-		} elseif ( is_array( $descriptor ) ) {
-			if ( $descriptor[self::NAME][0] === '@' ) {
-				$class = PPNode_Hash_Attr::class;
-			} else {
-				$class = self::class;
-			}
-		} else {
-			throw new MWException( __METHOD__ . ': invalid node descriptor' );
-		}
-		return new $class( $store, $index );
-	}
-
-	/**
-	 * Convert a node to XML, for debugging
-	 * @return string
-	 */
-	public function __toString() {
-		$inner = '';
-		$attribs = '';
-		for ( $node = $this->getFirstChild(); $node; $node = $node->getNextSibling() ) {
-			if ( $node instanceof PPNode_Hash_Attr ) {
-				$attribs .= ' ' . $node->name . '="' . htmlspecialchars( $node->value ) . '"';
-			} else {
-				$inner .= $node->__toString();
-			}
-		}
-		if ( $inner === '' ) {
-			return "<{$this->name}$attribs/>";
-		} else {
-			return "<{$this->name}$attribs>$inner</{$this->name}>";
-		}
-	}
-
-	/**
-	 * @return PPNode_Hash_Array
-	 */
-	public function getChildren() {
-		$children = [];
-		foreach ( $this->rawChildren as $i => $child ) {
-			$children[] = self::factory( $this->rawChildren, $i );
-		}
-		return new PPNode_Hash_Array( $children );
-	}
-
-	/**
-	 * Get the first child, or false if there is none. Note that this will
-	 * return a temporary proxy object: different instances will be returned
-	 * if this is called more than once on the same node.
-	 *
-	 * @return PPNode_Hash_Tree|PPNode_Hash_Attr|PPNode_Hash_Text|bool
-	 */
-	public function getFirstChild() {
-		if ( !isset( $this->rawChildren[0] ) ) {
-			return false;
-		} else {
-			return self::factory( $this->rawChildren, 0 );
-		}
-	}
-
-	/**
-	 * Get the next sibling, or false if there is none. Note that this will
-	 * return a temporary proxy object: different instances will be returned
-	 * if this is called more than once on the same node.
-	 *
-	 * @return PPNode_Hash_Tree|PPNode_Hash_Attr|PPNode_Hash_Text|bool
-	 */
-	public function getNextSibling() {
-		return self::factory( $this->store, $this->index + 1 );
-	}
-
-	/**
-	 * Get an array of the children with a given node name
-	 *
-	 * @param string $name
-	 * @return PPNode_Hash_Array
-	 */
-	public function getChildrenOfType( $name ) {
-		$children = [];
-		foreach ( $this->rawChildren as $i => $child ) {
-			if ( is_array( $child ) && $child[self::NAME] === $name ) {
-				$children[] = self::factory( $this->rawChildren, $i );
-			}
-		}
-		return new PPNode_Hash_Array( $children );
-	}
-
-	/**
-	 * Get the raw child array. For internal use.
-	 * @return array
-	 */
-	public function getRawChildren() {
-		return $this->rawChildren;
-	}
-
-	/**
-	 * @return bool
-	 */
-	public function getLength() {
-		return false;
-	}
-
-	/**
-	 * @param int $i
-	 * @return bool
-	 */
-	public function item( $i ) {
-		return false;
-	}
-
-	/**
-	 * @return string
-	 */
-	public function getName() {
-		return $this->name;
-	}
-
-	/**
-	 * Split a "<part>" node into an associative array containing:
-	 *  - name          PPNode name
-	 *  - index         String index
-	 *  - value         PPNode value
-	 *
-	 * @throws MWException
-	 * @return array
-	 */
-	public function splitArg() {
-		return self::splitRawArg( $this->rawChildren );
-	}
-
-	/**
-	 * Like splitArg() but for a raw child array. For internal use only.
-	 * @param array $children
-	 * @return array
-	 */
-	public static function splitRawArg( array $children ) {
-		$bits = [];
-		foreach ( $children as $i => $child ) {
-			if ( !is_array( $child ) ) {
-				continue;
-			}
-			if ( $child[self::NAME] === 'name' ) {
-				$bits['name'] = new self( $children, $i );
-				if ( isset( $child[self::CHILDREN][0][self::NAME] )
-					&& $child[self::CHILDREN][0][self::NAME] === '@index'
-				) {
-					$bits['index'] = $child[self::CHILDREN][0][self::CHILDREN][0];
-				}
-			} elseif ( $child[self::NAME] === 'value' ) {
-				$bits['value'] = new self( $children, $i );
-			}
-		}
-
-		if ( !isset( $bits['name'] ) ) {
-			throw new MWException( 'Invalid brace node passed to ' . __METHOD__ );
-		}
-		if ( !isset( $bits['index'] ) ) {
-			$bits['index'] = '';
-		}
-		return $bits;
-	}
-
-	/**
-	 * Split an "<ext>" node into an associative array containing name, attr, inner and close
-	 * All values in the resulting array are PPNodes. Inner and close are optional.
-	 *
-	 * @throws MWException
-	 * @return array
-	 */
-	public function splitExt() {
-		return self::splitRawExt( $this->rawChildren );
-	}
-
-	/**
-	 * Like splitExt() but for a raw child array. For internal use only.
-	 * @param array $children
-	 * @return array
-	 */
-	public static function splitRawExt( array $children ) {
-		$bits = [];
-		foreach ( $children as $i => $child ) {
-			if ( !is_array( $child ) ) {
-				continue;
-			}
-			switch ( $child[self::NAME] ) {
-				case 'name':
-					$bits['name'] = new self( $children, $i );
-					break;
-				case 'attr':
-					$bits['attr'] = new self( $children, $i );
-					break;
-				case 'inner':
-					$bits['inner'] = new self( $children, $i );
-					break;
-				case 'close':
-					$bits['close'] = new self( $children, $i );
-					break;
-			}
-		}
-		if ( !isset( $bits['name'] ) ) {
-			throw new MWException( 'Invalid ext node passed to ' . __METHOD__ );
-		}
-		return $bits;
-	}
-
-	/**
-	 * Split an "<h>" node
-	 *
-	 * @throws MWException
-	 * @return array
-	 */
-	public function splitHeading() {
-		if ( $this->name !== 'h' ) {
-			throw new MWException( 'Invalid h node passed to ' . __METHOD__ );
-		}
-		return self::splitRawHeading( $this->rawChildren );
-	}
-
-	/**
-	 * Like splitHeading() but for a raw child array. For internal use only.
-	 * @param array $children
-	 * @return array
-	 */
-	public static function splitRawHeading( array $children ) {
-		$bits = [];
-		foreach ( $children as $i => $child ) {
-			if ( !is_array( $child ) ) {
-				continue;
-			}
-			if ( $child[self::NAME] === '@i' ) {
-				$bits['i'] = $child[self::CHILDREN][0];
-			} elseif ( $child[self::NAME] === '@level' ) {
-				$bits['level'] = $child[self::CHILDREN][0];
-			}
-		}
-		if ( !isset( $bits['i'] ) ) {
-			throw new MWException( 'Invalid h node passed to ' . __METHOD__ );
-		}
-		return $bits;
-	}
-
-	/**
-	 * Split a "<template>" or "<tplarg>" node
-	 *
-	 * @throws MWException
-	 * @return array
-	 */
-	public function splitTemplate() {
-		return self::splitRawTemplate( $this->rawChildren );
-	}
-
-	/**
-	 * Like splitTemplate() but for a raw child array. For internal use only.
-	 * @param array $children
-	 * @return array
-	 */
-	public static function splitRawTemplate( array $children ) {
-		$parts = [];
-		$bits = [ 'lineStart' => '' ];
-		foreach ( $children as $i => $child ) {
-			if ( !is_array( $child ) ) {
-				continue;
-			}
-			switch ( $child[self::NAME] ) {
-				case 'title':
-					$bits['title'] = new self( $children, $i );
-					break;
-				case 'part':
-					$parts[] = new self( $children, $i );
-					break;
-				case '@lineStart':
-					$bits['lineStart'] = '1';
-					break;
-			}
-		}
-		if ( !isset( $bits['title'] ) ) {
-			throw new MWException( 'Invalid node passed to ' . __METHOD__ );
-		}
-		$bits['parts'] = new PPNode_Hash_Array( $parts );
-		return $bits;
-	}
-}
-
-/**
- * @ingroup Parser
- */
-// phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
-class PPNode_Hash_Text implements PPNode {
-
-	public $value;
-	private $store, $index;
-
-	/**
-	 * Construct an object using the data from $store[$index]. The rest of the
-	 * store array can be accessed via getNextSibling().
-	 *
-	 * @param array $store
-	 * @param int $index
-	 */
-	public function __construct( array $store, $index ) {
-		$this->value = $store[$index];
-		if ( !is_scalar( $this->value ) ) {
-			throw new MWException( __CLASS__ . ' given object instead of string' );
-		}
-		$this->store = $store;
-		$this->index = $index;
-	}
-
-	public function __toString() {
-		return htmlspecialchars( $this->value );
-	}
-
-	public function getNextSibling() {
-		return PPNode_Hash_Tree::factory( $this->store, $this->index + 1 );
-	}
-
-	public function getChildren() {
-		return false;
-	}
-
-	public function getFirstChild() {
-		return false;
-	}
-
-	public function getChildrenOfType( $name ) {
-		return false;
-	}
-
-	public function getLength() {
-		return false;
-	}
-
-	public function item( $i ) {
-		return false;
-	}
-
-	public function getName() {
-		return '#text';
-	}
-
-	public function splitArg() {
-		throw new MWException( __METHOD__ . ': not supported' );
-	}
-
-	public function splitExt() {
-		throw new MWException( __METHOD__ . ': not supported' );
-	}
-
-	public function splitHeading() {
-		throw new MWException( __METHOD__ . ': not supported' );
-	}
-}
-
-/**
- * @ingroup Parser
- */
-// phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
-class PPNode_Hash_Array implements PPNode {
-
-	public $value;
-
-	public function __construct( $value ) {
-		$this->value = $value;
-	}
-
-	public function __toString() {
-		return var_export( $this, true );
-	}
-
-	public function getLength() {
-		return count( $this->value );
-	}
-
-	public function item( $i ) {
-		return $this->value[$i];
-	}
-
-	public function getName() {
-		return '#nodelist';
-	}
-
-	public function getNextSibling() {
-		return false;
-	}
-
-	public function getChildren() {
-		return false;
-	}
-
-	public function getFirstChild() {
-		return false;
-	}
-
-	public function getChildrenOfType( $name ) {
-		return false;
-	}
-
-	public function splitArg() {
-		throw new MWException( __METHOD__ . ': not supported' );
-	}
-
-	public function splitExt() {
-		throw new MWException( __METHOD__ . ': not supported' );
-	}
-
-	public function splitHeading() {
-		throw new MWException( __METHOD__ . ': not supported' );
-	}
-}
-
-/**
- * @ingroup Parser
- */
-// phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
-class PPNode_Hash_Attr implements PPNode {
-
-	public $name, $value;
-	private $store, $index;
-
-	/**
-	 * Construct an object using the data from $store[$index]. The rest of the
-	 * store array can be accessed via getNextSibling().
-	 *
-	 * @param array $store
-	 * @param int $index
-	 */
-	public function __construct( array $store, $index ) {
-		$descriptor = $store[$index];
-		if ( $descriptor[PPNode_Hash_Tree::NAME][0] !== '@' ) {
-			throw new MWException( __METHOD__ . ': invalid name in attribute descriptor' );
-		}
-		$this->name = substr( $descriptor[PPNode_Hash_Tree::NAME], 1 );
-		$this->value = $descriptor[PPNode_Hash_Tree::CHILDREN][0];
-		$this->store = $store;
-		$this->index = $index;
-	}
-
-	public function __toString() {
-		return "<@{$this->name}>" . htmlspecialchars( $this->value ) . "</@{$this->name}>";
-	}
-
-	public function getName() {
-		return $this->name;
-	}
-
-	public function getNextSibling() {
-		return PPNode_Hash_Tree::factory( $this->store, $this->index + 1 );
-	}
-
-	public function getChildren() {
-		return false;
-	}
-
-	public function getFirstChild() {
-		return false;
-	}
-
-	public function getChildrenOfType( $name ) {
-		return false;
-	}
-
-	public function getLength() {
-		return false;
-	}
-
-	public function item( $i ) {
-		return false;
-	}
-
-	public function splitArg() {
-		throw new MWException( __METHOD__ . ': not supported' );
-	}
-
-	public function splitExt() {
-		throw new MWException( __METHOD__ . ': not supported' );
-	}
-
-	public function splitHeading() {
-		throw new MWException( __METHOD__ . ': not supported' );
-	}
-}
-- 
2.20.1