Changeset 58985 for trunk/src/wp-includes/html-api/class-wp-html-processor-state.php

Timestamp:

09/04/2024 04:32:37 AM (15 months ago)

Author:

dmsnell

Message:

HTML API: Respect document compat mode when handling CSS class names.

The HTML API has been behaving as if CSS class name selectors matched class names in an ASCII case-insensitive manner. This is only true if the document in question is set to quirks mode. Unfortunately most documents processed will be set to no-quirks mode, meaning that some CSS behaviors have been matching incorrectly when provided with case variants of class names.

In this patch, the CSS methods have been audited and updated to adhere to the rules governing ASCII case sensitivity when matching classes. This includes add_class(), remove_class(), has_class(), and class_list(). Now, it is assumed that a document is in no-quirks mode unless a full HTML parser infers quirks mode, and these methods will treat class names in a byte-for-byte manner. Otherwise, when a document is in quirks mode, the methods will compare the provided class names against existing class names for the tag in an ASCII case insensitive way, while class_list() will return a lower-cased version of the existing class names.

The lower-casing in class_list() is performed for consistency, since it's possible that multiple case variants of the same comparable class name exists on a tag in the input HTML.

Developed in ​https://github.com/WordPress/wordpress-develop/pull/7169
Discussed in https://core.trac.wordpress.org/ticket/61531

Props dmsnell, jonsurrell.
See #61531.

File:

• trunk/src/wp-includes/html-api/class-wp-html-processor-state.php (modified) (2 diffs)

trunk/src/wp-includes/html-api/class-wp-html-processor-state.php

@@ -301 +301 @@
 
     /**
-     * No-quirks mode document compatability mode.
-     *
-     * > In no-quirks mode, the behavior is (hopefully) the desired behavior
-     * > described by the modern HTML and CSS specifications.
-     *
-     * @since 6.7.0
-     *
-     * @var string
-     */
-    const NO_QUIRKS_MODE = 'no-quirks-mode';
-
-    /**
-     * Quirks mode document compatability mode.
-     *
-     * > In quirks mode, layout emulates behavior in Navigator 4 and Internet
-     * > Explorer 5. This is essential in order to support websites that were
-     * > built before the widespread adoption of web standards.
-     *
-     * @since 6.7.0
-     *
-     * @var string
-     */
-    const QUIRKS_MODE = 'quirks-mode';
-
-    /**
      * The stack of template insertion modes.
      *
@@ -381 +356 @@
      */
     public $insertion_mode = self::INSERTION_MODE_INITIAL;
-
-    /**
-     * Indicates if the document is in quirks mode or no-quirks mode.
-     *
-     * Impact on HTML parsing:
-     *
-     *  - In `NO_QUIRKS_MODE` CSS class and ID selectors match in a byte-for-byte
-     *    manner, otherwise for backwards compatability, class selectors are to
-     *    match in an ASCII case-insensitive manner.
-     *
-     *  - When not in `QUIRKS_MODE`, a TABLE start tag implicitly closes an open P tag
-     *    if one is in scope and open, otherwise the TABLE becomes a child of the P.
-     *
-     * `QUIRKS_MODE` impacts many styling-related aspects of an HTML document, but
-     * none of the other changes modifies how the HTML is parsed or selected.
-     *
-     * @see self::QUIRKS_MODE
-     * @see self::NO_QUIRKS_MODE
-     *
-     * @since 6.7.0
-     *
-     * @var string
-     */
-    public $document_mode = self::NO_QUIRKS_MODE;
 
     /**