Tests that the OffscreenCanvas can handle invalid arguments On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE". PASS canvas1.width is setWidth-1 PASS canvas1.height is setHeight-1 PASS canvas1.width is 0 PASS canvas1.height is 0 PASS new OffscreenCanvas(-1, -1) threw exception TypeError: Failed to construct 'OffscreenCanvas': Value is outside the 'unsigned long' value range.. PASS canvas2.width is 0 PASS canvas2.height is 0 PASS canvas2.width is setWidth-1 PASS canvas2.height is setHeight-1 PASS canvas2.width = -1 threw exception TypeError: Failed to set the 'width' property on 'OffscreenCanvas': Value is outside the 'unsigned long' value range.. PASS canvas2.height = -1 threw exception TypeError: Failed to set the 'height' property on 'OffscreenCanvas': Value is outside the 'unsigned long' value range.. PASS canvas2.width = obj threw exception TypeError: Failed to set the 'width' property on 'OffscreenCanvas': Value is not of type 'unsigned long'.. PASS canvas2.height = obj threw exception TypeError: Failed to set the 'height' property on 'OffscreenCanvas': Value is not of type 'unsigned long'.. PASS new OffscreenCanvas(obj, obj) threw exception TypeError: Failed to construct 'OffscreenCanvas': Value is not of type 'unsigned long'.. PASS successfullyParsed is true TEST COMPLETE