Bug 40271 – The HTML5 canvas 2d.drawImage.zerocanvas test does not pass

• Component: Layout and Rendering
• Status: RESOLVED FIXED

[Jan Erik Hanssen]

The HTML5 canvas 2d.drawImage.zerocanvas test does not pass, the INVALID_STATE_ERR DOM exception should be set when no image data is present.

http://philip.html5.org/tests/canvas/suite/tests/2d.drawImage.zerocanvas.html

[Andreas Kling]

Created attachment 59721 [details]
Proposed patch

[Andreas Kling]

Comment on attachment 59721 [details]
Proposed patch

Not quite there.

[Andreas Kling]

Created attachment 59726 [details]
Proposed patch v2

Proper patch.

See HTML5 spec at http://www.whatwg.org/specs/web-apps/current-work/#dom-context-2d-drawimage

"If the image argument is an HTMLCanvasElement object with either a horizontal dimension or a vertical dimension equal to zero, then the implementation must raise an INVALID_STATE_ERR exception."

[Andreas Kling]

Created attachment 60249 [details]
Proposed patch v3

Ok, a patch for *this* bug now :-)

[Darin Adler]

Comment on attachment 60249 [details]
Proposed patch v3

> +    if (!srcCanvasRect.width() || !srcCanvasRect.height()) {

Could you use srcCanvasRect.isEmpty() instead? If so, I think it would read nicer.

[WebKit Commit Bot]

Comment on attachment 60249 [details]
Proposed patch v3

Clearing flags on attachment: 60249

Committed r62277: <http://trac.webkit.org/changeset/62277>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.

[Andreas Kling]

(In reply to comment #5)
> (From update of attachment 60249 [details])
> > +    if (!srcCanvasRect.width() || !srcCanvasRect.height()) {
> 
> Could you use srcCanvasRect.isEmpty() instead? If so, I think it would read nicer.

I could, but FloatRect::isEmpty() checks (width <= 0 && height <= 0) which would open some incorrect code paths until bug 39149 is fixed.