From 0dca42efb4a1ae7bcd029bf02dbc49a6d7fb57df Mon Sep 17 00:00:00 2001
From: =?utf8?q?Bartosz=20Dziewo=C5=84ski?= <matma.rex@gmail.com>
Date: Sat, 17 Dec 2016 04:44:05 +0100
Subject: [PATCH] jquery.suggestions: Only highlight prefix matches

* jquery.highlightText: Add an option to highlight a prefix only.
* jquery.suggestions: Use the new option.

Bug: T27187
Change-Id: I097f012d2022334bbdb8cb32b256ae978aec57c7
---
 RELEASE-NOTES-1.29                           |  2 +
 resources/src/jquery/jquery.highlightText.js | 40 +++++++++++++++-----
 resources/src/jquery/jquery.suggestions.js   |  2 +-
 3 files changed, 34 insertions(+), 10 deletions(-)

diff --git a/RELEASE-NOTES-1.29 b/RELEASE-NOTES-1.29
index c04c8f780d..c92b522184 100644
--- a/RELEASE-NOTES-1.29
+++ b/RELEASE-NOTES-1.29
@@ -65,6 +65,8 @@ production.
 === Bug fixes in 1.29 ===
 * (T62604) Core parser functions returning a number now format the number according
   to the page content language, not wiki content language.
+* (T27187) Search suggestions based on jquery.suggestions will now correctly only
+  highlight prefix matches in the results.
 
 === Action API changes in 1.29 ===
 * Submitting sensitive authentication request parameters to action=clientlogin,
diff --git a/resources/src/jquery/jquery.highlightText.js b/resources/src/jquery/jquery.highlightText.js
index 3feca81cc1..a6b93733a6 100644
--- a/resources/src/jquery/jquery.highlightText.js
+++ b/resources/src/jquery/jquery.highlightText.js
@@ -8,18 +8,28 @@
 	$.highlightText = {
 
 		// Split our pattern string at spaces and run our highlight function on the results
-		splitAndHighlight: function ( node, pat ) {
+		splitAndHighlight: function ( node, text ) {
 			var i,
-				patArray = pat.split( ' ' );
-			for ( i = 0; i < patArray.length; i++ ) {
-				if ( patArray[ i ].length === 0 ) {
+				words = text.split( ' ' );
+			for ( i = 0; i < words.length; i++ ) {
+				if ( words[ i ].length === 0 ) {
 					continue;
 				}
-				$.highlightText.innerHighlight( node, patArray[ i ] );
+				$.highlightText.innerHighlight(
+					node,
+					new RegExp( '(^|\\s)' + mw.RegExp.escape( words[ i ] ), 'i' )
+				);
 			}
 			return node;
 		},
 
+		prefixHighlight: function ( node, prefix ) {
+			$.highlightText.innerHighlight(
+				node,
+				new RegExp( '(^)' + mw.RegExp.escape( prefix ), 'i' )
+			);
+		},
+
 		// scans a node looking for the pattern and wraps a span around each match
 		innerHighlight: function ( node, pat ) {
 			var i, match, pos, spannode, middlebit, middleclone;
@@ -28,7 +38,7 @@
 				// non latin characters can make regex think a new word has begun: do not use \b
 				// http://stackoverflow.com/questions/3787072/regex-wordwrap-with-utf8-characters-in-js
 				// look for an occurrence of our pattern and store the starting position
-				match = node.data.match( new RegExp( '(^|\\s)' + mw.RegExp.escape( pat ), 'i' ) );
+				match = node.data.match( pat );
 				if ( match ) {
 					pos = match.index + match[ 1 ].length; // include length of any matched spaces
 					// create the span wrapper for the matched text
@@ -37,7 +47,7 @@
 					// shave off the characters preceding the matched text
 					middlebit = node.splitText( pos );
 					// shave off any unmatched text off the end
-					middlebit.splitText( pat.length );
+					middlebit.splitText( match[ 0 ].length - match[ 1 ].length );
 					// clone for appending to our span
 					middleclone = middlebit.cloneNode( true );
 					// append the matched text node to the span
@@ -63,11 +73,23 @@
 		}
 	};
 
-	$.fn.highlightText = function ( matchString ) {
+	/**
+	 * Highlight certain text in current nodes (by wrapping it in `<span class="highlight">...</span>`).
+	 *
+	 * @param {string} matchString String to match
+	 * @param {Object} [options]
+	 * @param {string} [options.method='splitAndHighlight'] Method of matching to use, one of:
+	 *   - 'splitAndHighlight': Split `matchString` on spaces, then match each word separately.
+	 *   - 'prefixHighlight': Match `matchString` at the beginning of text only.
+	 * @return {[type]} [description]
+	 */
+	$.fn.highlightText = function ( matchString, options ) {
+		options = options || {};
+		options.method = options.method || 'splitAndHighlight';
 		return this.each( function () {
 			var $el = $( this );
 			$el.data( 'highlightText', { originalText: $el.text() } );
-			$.highlightText.splitAndHighlight( this, matchString );
+			$.highlightText[ options.method ]( this, matchString );
 		} );
 	};
 
diff --git a/resources/src/jquery/jquery.suggestions.js b/resources/src/jquery/jquery.suggestions.js
index f3e4e09313..8c1739c547 100644
--- a/resources/src/jquery/jquery.suggestions.js
+++ b/resources/src/jquery/jquery.suggestions.js
@@ -375,7 +375,7 @@
 								}
 
 								if ( context.config.highlightInput ) {
-									$result.highlightText( context.data.prevText );
+									$result.highlightText( context.data.prevText, { method: 'prefixHighlight' } );
 								}
 
 								// Widen results box if needed (new width is only calculated here, applied later).
-- 
2.20.1