Add an API-only user preference for diff type

* Add an API-only user preference for diff type
* Retain query parameter stickiness but fix it so that the diff-type
  from user preferences does not leak into the query string. So the
  no-JS control continues to work. If a no-JS user has the inline
  preference set, respect it on the initial load, but add an explicit
  diff-type=table to the query string of the table link so that the
  preference can be overridden.
* Get the diff type from the initial state of the no-JS button. Infuse
  the widget to access the active property using the OOUI public API.
* For a logged-in user, when the JS toggle is clicked, fetch the new
  diff body and update the user preference.
* For an anonymous user, when the JS toggle is clicked, update the
  prev/next links to include the correct diff-type query parameter.

Bug: T336713
Change-Id: Ie409d79ac8222dfa6ec8fd170b76be088be80b3a

1 files changed, 17 insertions, 1 deletions

diff --git a/includes/diff/DifferenceEngine.php b/includes/diff/DifferenceEngine.php
index 0d895063f861..102efcd9bc5f 100644
--- a/includes/diff/DifferenceEngine.php
+++ b/includes/diff/DifferenceEngine.php
@@ -220,6 +220,11 @@ class DifferenceEngine extends ContextSource {
 	 */
 	private $slotDiffOptions = [];
 
+	/**
+	 * Extra query parameters to be appended to diff page links
+	 */
+	private $extraQueryParams = [];
+
 	/** @var ManifoldTextDiffer|null */
 	private $textDiffer;
 
@@ -708,7 +713,7 @@ class DifferenceEngine extends ContextSource {
 
 		$rollback = '';
 
-		$query = $this->slotDiffOptions;
+		$query = $this->extraQueryParams;
 		# Carry over 'diffonly' param via navigation links
 		if ( $diffOnly != MediaWikiServices::getInstance()
 			->getUserOptionsLookup()->getBoolOption( $user, 'diffonly' )
@@ -1509,6 +1514,17 @@ class DifferenceEngine extends ContextSource {
 	}
 
 	/**
+	 * Set query parameters to append to diff page links
+	 *
+	 * @since 1.41
+	 *
+	 * @param array $params
+	 */
+	public function setExtraQueryParams( $params ) {
+		$this->extraQueryParams = $params;
+	}
+
+	/**
 	 * Generate a diff, no caching.
 	 *
 	 * @since 1.21