Merge "output: Narrow Title type hint to LinkTarget"

[lhc/web/wiklou.git] / includes / resourceloader / ResourceLoaderClientHtml.php

diff --git a/includes/resourceloader/ResourceLoaderClientHtml.php b/includes/resourceloader/ResourceLoaderClientHtml.php
index d59e1c8..ea35de6 100644 (file)
--- a/includes/resourceloader/ResourceLoaderClientHtml.php
+++ b/includes/resourceloader/ResourceLoaderClientHtml.php
@@ -143,15 +143,15 @@ class ResourceLoaderClientHtml {
 
                        $group = $module->getGroup();
                        $context = $this->getContext( $group, ResourceLoaderModule::TYPE_COMBINED );
-                       if ( $module->isKnownEmpty( $context ) ) {
-                               // Avoid needless request or embed for empty module
-                               $data['states'][$name] = 'ready';
-                               continue;
-                       }
+                       $shouldEmbed = $module->shouldEmbedModule( $this->context );
 
-                       if ( $group === 'user' || $module->shouldEmbedModule( $this->context ) ) {
-                               // Call makeLoad() to decide how to load these, instead of
-                               // loading via mw.loader.load().
+                       if ( ( $group === 'user' || $shouldEmbed ) && $module->isKnownEmpty( $context ) ) {
+                               // This is a user-specific or embedded module, which means its output
+                               // can be specific to the current page or user. As such, we can optimise
+                               // the way we load it based on the current version of the module.
+                               // Avoid needless embed for empty module, preset ready state.
+                               $data['states'][$name] = 'ready';
+                       } elseif ( $group === 'user' || $shouldEmbed ) {
                                // - For group=user: We need to provide a pre-generated load.php
                                //   url to the client that has the 'user' and 'version' parameters
                                //   filled in. Without this, the client would wrongly use the static
@@ -187,15 +187,30 @@ class ResourceLoaderClientHtml {
 
                        $group = $module->getGroup();
                        $context = $this->getContext( $group, ResourceLoaderModule::TYPE_STYLES );
-                       // Avoid needless request for empty module
-                       if ( !$module->isKnownEmpty( $context ) ) {
-                               if ( $module->shouldEmbedModule( $this->context ) ) {
-                                       // Embed via style element
+                       if ( $module->shouldEmbedModule( $this->context ) ) {
+                               // Avoid needless embed for private embeds we know are empty.
+                               // (Set "ready" state directly instead, which we do a few lines above.)
+                               if ( !$module->isKnownEmpty( $context ) ) {
+                                       // Embed via <style> element
                                        $data['embed']['styles'][] = $name;
-                               } else {
-                                       // Load from load.php?only=styles via <link rel=stylesheet>
-                                       $data['styles'][] = $name;
                                }
+                       // For other style modules, always request them, regardless of whether they are
+                       // currently known to be empty. Because:
+                       // 1. Those modules are requested in batch, so there is no extra request overhead
+                       //    or extra HTML element to be avoided.
+                       // 2. Checking isKnownEmpty for those can be expensive and slow down page view
+                       //    generation (T230260).
+                       // 3. We don't want cached HTML to vary on the current state of a module.
+                       //    If the module becomes non-empty a few minutes later, it should start working
+                       //    on cached HTML without requiring a purge.
+                       //
+                       // But, user-specific modules:
+                       // * ... are used on page views not publicly cached.
+                       // * ... are in their own group and thus a require a request we can avoid
+                       // * ... have known-empty status preloaded by ResourceLoader.
+                       } elseif ( $group !== 'user' || !$module->isKnownEmpty( $context ) ) {
+                               // Load from load.php?only=styles via <link rel=stylesheet>
+                               $data['styles'][] = $name;
                        }
                        $deprecation = $module->getDeprecationInformation();
                        if ( $deprecation ) {
@@ -225,19 +240,22 @@ class ResourceLoaderClientHtml {
         * - Inline scripts can't be asynchronous.
         * - For styles, earlier is better.
         *
+        * @param string|null $nojsClass Class name that caller uses on HTML document element
         * @return string|WrappedStringList HTML
         */
-       public function getHeadHtml() {
+       public function getHeadHtml( $nojsClass = null ) {
                $nonce = $this->options['nonce'];
                $data = $this->getData();
                $chunks = [];
 
                // Change "client-nojs" class to client-js. This allows easy toggling of UI components.
                // This must happen synchronously on every page view to avoid flashes of wrong content.
-               // See also #getDocumentAttributes() and /resources/src/startup.js.
-               $script = <<<'JAVASCRIPT'
-document.documentElement.className = document.documentElement.className
-       .replace( /(^|\s)client-nojs(\s|$)/, "$1client-js$2" );
+               // See also startup/startup.js.
+               $nojsClass = $nojsClass ?? $this->getDocumentAttributes()['class'];
+               $jsClass = preg_replace( '/(^|\s)client-nojs(\s|$)/', '$1client-js$2', $nojsClass );
+               $jsClassJson = ResourceLoader::encodeJsonForScript( $jsClass );
+               $script = <<<JAVASCRIPT
+document.documentElement.className = {$jsClassJson};
 JAVASCRIPT;
 
                // Inline script: Declare mw.config variables for this page.
@@ -460,7 +478,7 @@ JAVASCRIPT;
                                                        ] );
                                                } else {
                                                        $chunk = ResourceLoader::makeInlineScript(
-                                                               Xml::encodeJsCall( 'mw.loader.load', [ $url ] ),
+                                                               'mw.loader.load(' . ResourceLoader::encodeJsonForScript( $url ) . ');',
                                                                $nonce
                                                        );
                                                }