Use exchars instead of exsentences for the extract

To avoid sentence parsing bugs in other languages.

We have to artificially remove the always-added ellipsis from textextracts to
mimic previous behavior, and we'll add ellipsis via CSS afterwards.

Bug: T135824
Change-Id: Idf27f2fd18f7197e588c609eeb62ac8fc80626d7

resources/ext.popups.renderer.article.js

@@ -8,6 +8,12 @@
 	var article = {},
 		$window = $( window );
 
+	/**
+	 * Number of chars to request for the article extract
+	 * @property CHARS
+	 */
+	article.CHARS = 525;
+
 	/**
 	 * Size constants for popup images
 	 * @property SIZES
@@ -55,7 +61,7 @@
 			formatversion: 2,
 			redirects: true,
 			exintro: true,
-			exsentences: 5,
+			exchars: article.CHARS,
 			// there is an added geometric limit on .mwe-popups-extract
 			// so that text does not overflow from the card
 			explaintext: true,
@@ -100,6 +106,8 @@
 				return;
 			}
 
+			re.query.pages[ 0 ].extract = removeEllipsis( re.query.pages[ 0 ].extract );
+
 			mw.popups.render.cache[ href ] = {};
 			mw.popups.render.cache[ href ].popup = article.createPopup( re.query.pages[ 0 ], href );
 			mw.popups.render.cache[ href ].getOffset = article.getOffset;
@@ -667,4 +675,11 @@
 	 */
 	mw.popups.render.getClosestYPosition = getClosestYPosition;
 
+	/**
+	 * Remove ellipsis if exists at the end
+	 */
+	function removeEllipsis( text ) {
+		return text.replace( /\.\.\.$/, '' );
+	}
+
 } )( jQuery, mediaWiki );