From d4cd816b6ff2dc9b7c5e82b3e40e367fedc3949f Mon Sep 17 00:00:00 2001
From: Ed Sanders <esanders@wikimedia.org>
Date: Mon, 21 Jul 2014 14:32:17 +0100
Subject: [PATCH] MWReferenceSearchWidget buildIndex optimisations

* Each item builds an MWReferenceModel which creates a document
  slice clone. This is very expensive and we only use the model
  for getting basic attributes, so defer the evaluation of the
  document.
* $.show is expensive and, in this case, unnecessary.

Change-Id: I99abc4c1b17f05559a9cae68b15121a8be6d23fb
---
 .../ve-mw/dm/models/ve.dm.MWReferenceModel.js | 24 ++++++++++++-------
 .../widgets/ve.ui.MWReferenceSearchWidget.js  |  2 +-
 2 files changed, 17 insertions(+), 9 deletions(-)

diff --git a/modules/ve-mw/dm/models/ve.dm.MWReferenceModel.js b/modules/ve-mw/dm/models/ve.dm.MWReferenceModel.js
index 8171b28da4..7e02fb9ef1 100644
--- a/modules/ve-mw/dm/models/ve.dm.MWReferenceModel.js
+++ b/modules/ve-mw/dm/models/ve.dm.MWReferenceModel.js
@@ -23,6 +23,7 @@ ve.dm.MWReferenceModel = function VeDmMWReferenceModel() {
 	this.listIndex = null;
 	this.group = '';
 	this.doc = null;
+	this.deferDoc = null;
 };
 
 /* Inheritance */
@@ -47,7 +48,10 @@ ve.dm.MWReferenceModel.static.newFromReferenceNode = function ( node ) {
 	ref.setListGroup( attr.listGroup );
 	ref.setListIndex( attr.listIndex );
 	ref.setGroup( attr.refGroup );
-	ref.setDocument( doc.cloneFromRange( internalList.getItemNode( attr.listIndex ).getRange() ) );
+	ref.deferDoc = function () {
+		// cloneFromRange is very expensive, so lazy evaluate it
+		return doc.cloneFromRange( internalList.getItemNode( attr.listIndex ).getRange() );
+	};
 
 	return ref;
 };
@@ -149,7 +153,7 @@ ve.dm.MWReferenceModel.prototype.updateInternalItem = function ( surfaceModel )
 	itemNodeRange = internalList.getItemNode( this.listIndex ).getRange();
 	surfaceModel.change( ve.dm.Transaction.newFromRemoval( doc, itemNodeRange, true ) );
 	surfaceModel.change(
-		ve.dm.Transaction.newFromDocumentInsertion( doc, itemNodeRange.start, this.doc )
+		ve.dm.Transaction.newFromDocumentInsertion( doc, itemNodeRange.start, this.getDocument() )
 	);
 };
 
@@ -219,12 +223,16 @@ ve.dm.MWReferenceModel.prototype.getGroup = function () {
  */
 ve.dm.MWReferenceModel.prototype.getDocument = function () {
 	if ( !this.doc ) {
-		this.doc = new ve.dm.Document( [
-			{ 'type': 'paragraph', 'internal': { 'generated': 'wrapper' } },
-			{ 'type': '/paragraph' },
-			{ 'type': 'internalList' },
-			{ 'type': '/internalList' }
-		] );
+		if ( this.deferDoc ) {
+			this.doc = this.deferDoc();
+		} else {
+			this.doc = new ve.dm.Document( [
+				{ 'type': 'paragraph', 'internal': { 'generated': 'wrapper' } },
+				{ 'type': '/paragraph' },
+				{ 'type': 'internalList' },
+				{ 'type': '/internalList' }
+			] );
+		}
 	}
 	return this.doc;
 };
diff --git a/modules/ve-mw/ui/widgets/ve.ui.MWReferenceSearchWidget.js b/modules/ve-mw/ui/widgets/ve.ui.MWReferenceSearchWidget.js
index 815e7696b8..83a47819a9 100644
--- a/modules/ve-mw/ui/widgets/ve.ui.MWReferenceSearchWidget.js
+++ b/modules/ve-mw/ui/widgets/ve.ui.MWReferenceSearchWidget.js
@@ -131,7 +131,7 @@ ve.ui.MWReferenceSearchWidget.prototype.buildIndex = function ( internalList ) {
 			view.$element.find( 'a[href]' ).each( extractAttrs );
 
 			this.index.push( {
-				'$element': view.$element.clone().show(),
+				'$element': view.$element.clone(),
 				'text': text,
 				'reference': ref,
 				'citation': citation,