Remove browser sniff in attrs.js

[david-mark]

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Do you want to request a feature or report a bug?

Neither.

What is the current behavior?

Depends on browser and configuration. Relies on browser sniffing. May "work" by coincidence in all supported browsers, but could fail in future.

Either use a feature test for this or simply set the property if the attribute is missing, regardless of what browser we think it is. Certainly no harm will come from that. Also not sure why prop is used instead of just setting the property.

if (propName) element[propName] = attr[name];

For all we know some non-IE browser version may come out tomorrow and demonstrate the same bug.

http://jibbering.com/faq/notes/detect-browser/

// Support: IE 9-11 only
// On IE, if "ng:src" directive declaration is used and "src" attribute doesn't exist
// then calling element.setAttribute('src', 'foo') doesn't do anything, so we need
// to set the property as well to achieve the desired effect.
// We use attr[attrName] value since $set can sanitize the url.
if (msie && propName) element.prop(propName, attr[name]);

Test would be something like:

var elDummyImage = document.createElement('img');
document.body.appendChild(elDummyImage);
elDummyImage.setAttribute('src', 'test');

var problemSettingImgAttribute =  elDummyImage.src === '';

document.body.removeChild(elDummyImage);

Then make a direct inference based on the test result:

if (propName && problemSettingImgAttribute) element[propName] = attr[name];

Not sure why we aren't just setting the property in the first place. Will certainly cause the IMG to sprout a SRC attribute.

[gkalpak]

I couldn't reproduce the issue tbh (using IE11 in IE<11 mode), but I am not sure if we can reliably test for the problem. So, I am not sure if we can reliably detect the problem.

Also, I am not sure what the exact problem is:

• Is it that the src property is not updated?
• Is it that the src property is updated, but the image is not fetched?

(If it is the latter, I don't think we can reliably detect the failure.)

Bottomline:
I am not opposed to changing this if we can "feature-detect" reliably and I would be happy to review any pull requests, but I don't think this is worth putting anyone's time into tbh.