From f23dba1c10134b7a83998ac537df62042c237e4c Mon Sep 17 00:00:00 2001
From: Jonas Jenwald <jonas.jenwald@gmail.com>
Date: Wed, 31 Oct 2018 18:15:23 +0100
Subject: [PATCH] Change `canvasInRendering` to a `WeakSet` instead of a
`WeakMap`
Note how nowhere in the code `canvasInRendering.get()` is ever called, and that this structure is really only used to store references to `<canvas>` DOM elements.
The reason for this being a `WeakMap` is probably because at the time we weren't using `core-js` polyfills yet, and since there already existed a manually implemented `WeakMap` polyfill it was probably simpler to use that.
---
src/display/api.js | 4 ++--
src/shared/compatibility.js | 8 ++++++++
2 files changed, 10 insertions(+), 2 deletions(-)
diff --git a/src/display/api.js b/src/display/api.js
index ca192afe4..1cf958848 100644
--- a/src/display/api.js
+++ b/src/display/api.js
@@ -2365,7 +2365,7 @@ var RenderTask = (function RenderTaskClosure() {
* @ignore
*/
var InternalRenderTask = (function InternalRenderTaskClosure() {
- let canvasInRendering = new WeakMap();
+ let canvasInRendering = new WeakSet();
function InternalRenderTask(callback, params, objs, commonObjs, operatorList,
pageNumber, canvasFactory, webGLContext,
@@ -2408,7 +2408,7 @@ var InternalRenderTask = (function InternalRenderTaskClosure() {
'Use different canvas or ensure previous operations were ' +
'cancelled or completed.');
}
- canvasInRendering.set(this._canvas, this);
+ canvasInRendering.add(this._canvas);
}
if (this._pdfBug && globalScope.StepperManager &&
diff --git a/src/shared/compatibility.js b/src/shared/compatibility.js
index 66eff0591..ff99f9b15 100644
--- a/src/shared/compatibility.js
+++ b/src/shared/compatibility.js
@@ -187,6 +187,14 @@ const hasDOM = typeof window === 'object' && typeof document === 'object';
globalScope.WeakMap = require('core-js/fn/weak-map');
})();
+// Support: IE11
+(function checkWeakSet() {
+ if (globalScope.WeakSet) {
+ return;
+ }
+ globalScope.WeakSet = require('core-js/fn/weak-set');
+})();
+
// Provides support for String.codePointAt in legacy browsers.
// Support: IE11.
(function checkStringCodePointAt() {