Get tests reporting failures again

src/Terminal.ts

@@ -43,6 +43,7 @@ import { BellSound } from './utils/Sounds';
 import { DEFAULT_ANSI_COLORS } from './renderer/ColorManager';
 import { IMouseZoneManager } from './input/Interfaces';
 import { MouseZoneManager } from './input/MouseZoneManager';
+import { initialize as initializeCharAtlas } from './renderer/CharAtlas';
 
 // Declare for RequireJS in loadAddon
 declare var define: any;
@@ -562,6 +563,8 @@ export class Terminal extends EventEmitter implements ITerminal, IInputHandlingT
     this.document = this.parent.ownerDocument;
     this.body = <HTMLBodyElement>this.document.body;
 
+    initializeCharAtlas(this.document);
+
     // Create main element container
     this.element = this.document.createElement('div');
     this.element.classList.add('terminal');

src/renderer/CharAtlas.ts

@@ -91,12 +91,20 @@ function configEquals(a: ICharAtlasConfig, b: ICharAtlasConfig): boolean {
       a.colors.foreground === b.colors.foreground;
 }
 
+let generator: CharAtlasGenerator;
+
+export function initialize(document: Document): void {
+  if (!generator) {
+    generator = new CharAtlasGenerator(document);
+  }
+}
+
 class CharAtlasGenerator {
   private _canvas: HTMLCanvasElement;
   private _ctx: CanvasRenderingContext2D;
 
-  constructor() {
-    this._canvas = document.createElement('canvas');
+  constructor(private _document: Document) {
+    this._canvas = this._document.createElement('canvas');
     this._ctx = this._canvas.getContext('2d');
     this._ctx.scale(window.devicePixelRatio, window.devicePixelRatio);
   }
@@ -147,7 +155,7 @@ class CharAtlasGenerator {
     if (!('createImageBitmap' in window)) {
       // Regenerate canvas and context as they are now owned by the char atlas
       const result = this._canvas;
-      this._canvas = document.createElement('canvas');
+      this._canvas = this._document.createElement('canvas');
       this._ctx = this._canvas.getContext('2d');
       this._ctx.scale(window.devicePixelRatio, window.devicePixelRatio);
       return result;
@@ -159,5 +167,3 @@ class CharAtlasGenerator {
     return promise;
   }
 }
-
-const generator = new CharAtlasGenerator();