Merge "Warn when target comments in a link can't be found"

extension.json

@@ -121,6 +121,8 @@
 				"discussiontools-replylink",
 				"discussiontools-replywidget-loading",
 				"discussiontools-replywidget-watchthis",
+				"discussiontools-target-comment-missing",
+				"discussiontools-target-comments-missing",
 				"discussiontools-topicsubscription-button-subscribe",
 				"discussiontools-topicsubscription-button-subscribe-tooltip",
 				"discussiontools-topicsubscription-button-unsubscribe",

i18n/en.json

@@ -99,6 +99,8 @@
 	"discussiontools-replywidget-transcluded": "Your comment will be saved at [[$1]].",
 	"discussiontools-replywidget-watchthis": "Add this page to your [[Special:Watchlist|watchlist]]",
 	"discussiontools-signature-prefix": " ",
+	"discussiontools-target-comment-missing": "This comment could not be found. It might have been deleted or moved.",
+	"discussiontools-target-comments-missing": "New comments could not be found. They might have been deleted or moved.",
 	"discussiontools-topicsubscription-action-unsubscribe-button": "Unsubscribe",
 	"discussiontools-topicsubscription-action-unsubscribe-prompt": "Unsubscribe from this topic?",
 	"discussiontools-topicsubscription-button-subscribe": "subscribe",

i18n/qqq.json

@@ -110,6 +110,8 @@
 	"discussiontools-replywidget-transcluded": "Message explaining that the comment will be saved on a different page than the one you're viewing right now (because it was transcluded from it). Parameter: $1 – page name",
 	"discussiontools-replywidget-watchthis": "Label for a checkbox in the reply widget. It is used instead of the usual {{msg-mw|watchthis}} to distinguish the watchlist functionality from [[mw:Talk_pages_project/Feature_summary#Topic_subscriptions|topic subscriptions]].\n{{Identical|Add this page to your watchlist}}",
 	"discussiontools-signature-prefix": "{{optional}}\nWikitext that prefixes the signature. The prefix and signature will be appended directly to the message, so this must include a leading space if a gap is desired.\n\nThis message intentionally doesn't use the prefix from {{msg-mw|sig-text}}, because it is not actually commonly used on many wikis, but you can include it in the translation if that is the convention in your language.\n{{Format|plain}}",
+	"discussiontools-target-comment-missing": "Message shown in a popup when the user follows a link that would highlight a '''single''' comment on a talk page, e.g. [https://en.wikipedia.org/wiki/User_talk:Example#c-Example1-2019-06-26T08:00:00.000Z-Example_discussion_title], but the comment doesn't exist on the page any more. Such links are used in notifications, or can be used in comments by other users.\n\nSee also for multiple comments: {{msg-mw|discussiontools-target-comments-missing}}",
+	"discussiontools-target-comments-missing": "Message shown in a popup when the user follows a link that would highlight potentially '''multiple new''' comments on a talk page, but the exact number is unknown, e.g. [https://en.wikipedia.org/w/index.php?title=User_talk:Example&dtnewcommentssince=c-Example1-2019-06-26T10:20:00.000Z-Example2-2019-06-26T10:10:00.000Z], but none of these comments exist on the page any more. Such links are generated by notifications.\n\nSee also for a single comments: {{msg-mw|discussiontools-target-comment-missing}}",
 	"discussiontools-topicsubscription-action-unsubscribe-button": "Button to unsubscribe from a topic.\n{{identical|Unsubscribe}}",
 	"discussiontools-topicsubscription-action-unsubscribe-prompt": "Prompt shown when about to unsubscribe from a topic on an action page.",
 	"discussiontools-topicsubscription-button-subscribe": "Label for the subscribe link added to each section. Use the same casing as section edit links.\n\nAppears in the same area as:\n* {{msg-mw|editsection}}\n* {{msg-mw|visualeditor-ca-editsource-section}}\n* {{msg-mw|discussiontools-topicsubscription-button-unsubscribe}}\n* {{msg-mw|discussiontools-replylink}}",

modules/controller.js

@@ -513,6 +513,7 @@ function updateSubscriptionStates( $container, headingsToUpdate ) {
 }
 
 var $highlightedTarget = null;
+var missingTargetNotifPromise = null;
 /**
  * Highlight the comment(s) on the page associated with the URL hash or query string
  *
@@ -527,6 +528,12 @@ function highlightTargetComment( threadItemSet, noScroll ) {
 			$highlightedTarget.remove();
 			$highlightedTarget = null;
 		}
+		if ( missingTargetNotifPromise ) {
+			missingTargetNotifPromise.then( function ( notif ) {
+				notif.close();
+			} );
+			missingTargetNotifPromise = null;
+		}
 		// eslint-disable-next-line no-jquery/no-global-selector
 		var targetElement = $( ':target' )[ 0 ];
 
@@ -538,6 +545,15 @@ function highlightTargetComment( threadItemSet, noScroll ) {
 			return;
 		}
 
+		if ( location.hash.match( /^#c-/ ) && !targetElement ) {
+			missingTargetNotifPromise = mw.loader.using( 'mediawiki.notification' ).then( function () {
+				return mw.notification.notify(
+					mw.message( 'discussiontools-target-comment-missing' ).parse(),
+					{ type: 'warn', autoHide: false }
+				);
+			} );
+		}
+
 		var uri;
 		try {
 			uri = new mw.Uri( location.href );
@@ -567,6 +583,9 @@ function highlightTargetComment( threadItemSet, noScroll ) {
 function highlightNewComments( threadItemSet, noScroll, newCommentIds, newCommentsSinceId, inThread ) {
 	newCommentIds = newCommentIds || [];
 
+	var highlightsRequested = newCommentIds.length || newCommentsSinceId;
+	var highlightsRequestedSingle = !newCommentsSinceId && newCommentIds.length === 1;
+
 	if ( newCommentsSinceId ) {
 		var newCommentsSince = threadItemSet.findCommentById( newCommentsSinceId );
 		if ( newCommentsSince && newCommentsSince instanceof CommentItem ) {
@@ -615,6 +634,17 @@ function highlightNewComments( threadItemSet, noScroll, newCommentIds, newCommen
 			}
 			document.getElementById( comments[ topmostComment ].id ).scrollIntoView();
 		}
+	} else if ( highlightsRequested ) {
+		missingTargetNotifPromise = mw.loader.using( 'mediawiki.notification' ).then( function () {
+			return mw.notification.notify(
+				mw.message(
+					highlightsRequestedSingle ?
+						'discussiontools-target-comment-missing' :
+						'discussiontools-target-comments-missing'
+				).parse(),
+				{ type: 'warn', autoHide: false }
+			);
+		} );
 	}
 }
 
@@ -624,6 +654,13 @@ function highlightNewComments( threadItemSet, noScroll, newCommentIds, newCommen
  * @param {ThreadItemSet} threadItemSet
  */
 function clearHighlightTargetComment( threadItemSet ) {
+	if ( missingTargetNotifPromise ) {
+		missingTargetNotifPromise.then( function ( notif ) {
+			notif.close();
+		} );
+		missingTargetNotifPromise = null;
+	}
+
 	var uri;
 	try {
 		uri = new mw.Uri( location.href );