From 5bd4f88169e2fc5a45224d1518f989974ddf6f5d Mon Sep 17 00:00:00 2001
From: "Mark A. Hershberger" <mah@users.mediawiki.org>
Date: Mon, 21 Nov 2011 01:45:23 +0000
Subject: [PATCH] Fixes Bug 31865 - Tag <dws> for discarding whitespaces. Patch
 with parser tests from Van de Bugger

---
 includes/parser/Preprocessor_DOM.php  | 17 +++++
 includes/parser/Preprocessor_Hash.php | 14 +++++
 tests/parser/parserTests.txt          | 91 +++++++++++++++++++++++++++
 3 files changed, 122 insertions(+)

diff --git a/includes/parser/Preprocessor_DOM.php b/includes/parser/Preprocessor_DOM.php
index 066589f685..7803a70ec0 100644
--- a/includes/parser/Preprocessor_DOM.php
+++ b/includes/parser/Preprocessor_DOM.php
@@ -211,6 +211,9 @@ class Preprocessor_DOM implements Preprocessor {
 			$ignoredElements = array( 'includeonly' );
 			$xmlishElements[] = 'includeonly';
 		}
+		// `dws' stands for "discard white spaces". `<dws>' and all the whitespaces afer it are
+		// discarded.
+		$xmlishElements[] = 'dws';
 		$xmlishRegex = implode( '|', array_merge( $xmlishElements, $ignoredTags ) );
 
 		// Use "A" modifier (anchored) instead of "^", because ^ doesn't work with an offset
@@ -406,6 +409,20 @@ class Preprocessor_DOM implements Preprocessor {
 				}
 
 				$tagStartPos = $i;
+
+				// Handle tag `dws'.
+				if ( $name == 'dws' ) {
+					$i = $tagEndPos + 1;
+					if ( preg_match( '/\s*/', $text, $matches, 0, $i ) ) {
+						$i += strlen( $matches[0] );
+					}
+					$accum .=
+						'<ignore>' .
+							htmlspecialchars( substr( $text, $tagStartPos, $i - $tagStartPos ) ) .
+						'</ignore>';
+					continue;
+				}
+
 				if ( $text[$tagEndPos-1] == '/' ) {
 					$attrEnd = $tagEndPos - 1;
 					$inner = null;
diff --git a/includes/parser/Preprocessor_Hash.php b/includes/parser/Preprocessor_Hash.php
index 2934181a50..ad5155b8e2 100644
--- a/includes/parser/Preprocessor_Hash.php
+++ b/includes/parser/Preprocessor_Hash.php
@@ -153,6 +153,9 @@ class Preprocessor_Hash implements Preprocessor {
 			$ignoredElements = array( 'includeonly' );
 			$xmlishElements[] = 'includeonly';
 		}
+		// `dws' stands for "discard white spaces". `<dws>' and all the whitespaces afer it are
+		// discarded.
+		$xmlishElements[] = 'dws';
 		$xmlishRegex = implode( '|', array_merge( $xmlishElements, $ignoredTags ) );
 
 		// Use "A" modifier (anchored) instead of "^", because ^ doesn't work with an offset
@@ -350,6 +353,17 @@ class Preprocessor_Hash implements Preprocessor {
 				}
 
 				$tagStartPos = $i;
+
+				// Handle tag dws.
+				if ( $name == 'dws' ) {
+					$i = $tagEndPos + 1;
+					if ( preg_match( '/\s*/', $text, $matches, 0, $i ) ) {
+						$i += strlen( $matches[0] );
+					}
+					$accum->addNodeWithText( 'ignore', substr( $text, $tagStartPos, $i - $tagStartPos ) );
+					continue;
+				}
+
 				if ( $text[$tagEndPos-1] == '/' ) {
 					// Short end tag
 					$attrEnd = $tagEndPos - 1;
diff --git a/tests/parser/parserTests.txt b/tests/parser/parserTests.txt
index 9a7fd40dfb..c331dd31a2 100644
--- a/tests/parser/parserTests.txt
+++ b/tests/parser/parserTests.txt
@@ -8930,6 +8930,97 @@ title=[[MediaWiki:bug32450.css]]
 </p>
 !! end
 
+!! test
+Bug 31865: HTML-style tag <dws> is recognized and discarded.
+!! input
+one<dws>two
+!! result
+<p>onetwo
+</p>
+!! end
+
+!! test
+Bug 31865: XML-style tag <dws/> is recognized and discarded.
+!! input
+one<dws/>two
+!! result
+<p>onetwo
+</p>
+!! end
+
+!! test
+Bug 31865: Spaces after <dws> tag are discarded.
+!! input
+one<dws>   two
+!! result
+<p>onetwo
+</p>
+!! end
+
+!! test
+Bug 31865: Tabs after <dws> tag are discarded too.
+!! input
+one<dws>			two
+!! result
+<p>onetwo
+</p>
+!! end
+
+!! test
+Bug 31865: Newlines after <dws> tag are discarded too.
+!! input
+one<dws>
+
+
+two
+!! result
+<p>onetwo
+</p>
+!! end
+
+!! test
+Bug 31865: Spaces before <dws> tag are not discarded.
+!! input
+one   <dws>two
+!! result
+<p>one   two
+</p>
+!! end
+
+!! test
+Bug 31865: <dws> Continuation is indented.
+!! input
+one<dws>
+	two
+!! result
+<p>onetwo
+</p>
+!! end
+
+!! test
+Bug 31865: <dws> List item continuation.
+!! input
+* one<dws>
+	two
+* three
+!! result
+<ul><li> onetwo
+</li><li> three
+</li></ul>
+
+!! end
+
+!! test
+Bug 31865: <dws/> XML-style; asterisk after the tag does not start list item. 
+!! input
+* one <dws/>
+* two
+!! result
+<ul><li> one * two
+</li></ul>
+
+!! end
+
 TODO:
 more images
 more tables
-- 
2.20.1