Function assertCanvasDisposing

test/unit/canvas_dispose.js:7–203

(klass)

}

function assertCanvasDisposing(klass) {

    QUnit.test('dispose', async function (assert) {
        const done = assert.async();
        const canvas = new klass(null, { renderOnAddRemove: false });
        assert.notOk(canvas.destroyed, 'should not have been destroyed yet');
        await canvas.dispose();
        assert.ok(canvas.destroyed, 'should have flagged `destroyed`');
        done();
    });

    QUnit.test('dispose: clear references sync', function (assert) {
        var el = fabric.getFabricDocument().createElement('canvas'),
            parentEl = fabric.getFabricDocument().createElement('div');

        el.width = 200; el.height = 200;
        parentEl.className = 'rootNode';
        parentEl.appendChild(el);

        fabric.config.configure({ devicePixelRatio: 1.25 });

        el.style.position = 'relative';
        var elStyle = el.style.cssText;
        assert.equal(elStyle, 'position: relative;', 'el style should not be empty');

        var canvas = new fabric.Canvas(el, { enableRetinaScaling: true, renderOnAddRemove: false });
        assert.equal(canvas.elements._originalCanvasStyle, elStyle, 'saved original canvas style for disposal');
        assert.notEqual(el.style.cssText, canvas.elements._originalCanvasStyle, 'canvas el style has been changed');
        assert.equal(el.getAttribute('data-fabric'), 'main', 'lowerCanvasEl should be marked by fabric');
        assert.ok(typeof canvas.dispose === 'function');
        assert.ok(typeof canvas.destroy === 'function');
        canvas.add(makeRect(), makeRect(), makeRect());
        canvas.item(0).animate({ scaleX: 10 });
        assert.equal(fabric.runningAnimations.length, 1, 'should have a running animation');
        canvas.dispose();
        assert.equal(canvas.disposed, true, 'dispose should flag disposed');
        assert.equal(el.hasAttribute('data-fabric'), false, 'dispose should clear lowerCanvasEl data-fabric attr');
        assert.equal(canvas.elements._originalCanvasStyle, undefined, 'removed original canvas style');
        assert.equal(el.style.cssText, elStyle, 'restored original canvas style');
        assert.equal(el.width, 200, 'restored width');
        assert.equal(el.height, 200, 'restored height');
    });


    QUnit.test('dispose: clear references async', async function (assert) {
        const canvas = new klass(null, { renderOnAddRemove: false });
        assert.ok(typeof canvas.dispose === 'function');
        assert.ok(typeof canvas.destroy === 'function');
        canvas.add(makeRect(), makeRect(), makeRect());
        const lowerCanvas = canvas.lowerCanvasEl;
        assert.equal(lowerCanvas.getAttribute('data-fabric'), 'main', 'lowerCanvasEl should be marked by fabric');
        await canvas.dispose();
        assert.equal(canvas.destroyed, true, 'dispose should flag destroyed');
        assert.equal(canvas.getObjects().length, 0, 'dispose should clear canvas');
        assert.equal(canvas.lowerCanvasEl, null, 'dispose should clear lowerCanvasEl');
        assert.equal(lowerCanvas.hasAttribute('data-fabric'), false, 'dispose should clear lowerCanvasEl data-fabric attr');
        assert.equal(canvas.contextContainer, null, 'dispose should clear contextContainer');
    });