srcset with no space after the comma

I'm trying to understand if this is the correct behavior - when there is no space after the comma the parsing fails.
The following will fail with 'Invalid srcset descriptor':

srcset.parse("banner-HD.jpg 2x,banner-phone.jpg 100w");

Due to the regular expression in the code: string.split(/,\s+/)

Changing to string.split(/,\s*/)

Will fix the problem.

Is that on purpose?