Canvas currently throws JS exceptions when JS attempts to draw 0 size elements (eg. when width, height, or radius, etc are 0). These should just be ignored per the spec.
Created attachment 11028 [details] Simple test case Simple test case, if it fails, it presents a red square, if it succeeds it presents a green square.
Created attachment 11029 [details] patch Patch that fixes problem
Comment on attachment 11029 [details] patch r=me. Please turn the testcase into a layout test and include it when you check in.
Comment on attachment 11029 [details] patch This patch breaks handling of NaN. We need to add test cases that pass non-numeric values (which turn into NaN) and then fix the code to say things like: if (!(r >= 0)) rather than if (r < 0) because expressions with NaN always yield false.
Looks like Oliver landed this patch long ago and didn't notice my review-. http://trac.webkit.org/projects/webkit/changeset/16993
Eek, i even discussed that one with you post landing ... will bang out a correction to the logic :(
Fxed this a while back (with correct inf handling)