As a starting point of information the test is against the FULL path to the file from WITHIN each asset directory.
Initially I thought perhaps his RegEx was in error, but it actually seems to be fine. The question may really be does the RegEx given match your needs. To break it down, here's the regex you gave:
/ckeditor\/.*/
Given the following provided file paths:
- ckeditor/blah.js
- ckeditor_blah.js
- ckEditor.main.js
- ckEditor/main.js
- in/ckeditor.css
- in/ckeditor/extra.css
- in/blockeditor/base.css
- ckeditor5/temp.js
This will match only lines 1, 6 and 7, this is because it is looking for paths that contain the text "ckeditor/" in them. The ".*" in the Regex is actually superfluous (I believe) since it is only adding that the string can contain 0 to infinite characters after "ckeditor/".
The other thing to note is that this is CASE SENSITIVE, so if your file path is actually ckEditor/main.js as in the 4th line of the example above it will not match. If you need the RegEx to be case-insensitive, use:
/ckeditor\/.*/i
Hopefully this helps you dig through the problem... Here's some supplemental examples to provide more starting points:
/^ckeditor/i
This will match lines 1, 2, 3, 4 and 8 in the example above, as it will search for any path starting with "ckeditor" and is case-INsensitive.
/[\/]*ckeditor[\/]/i
This will match lines 1, 4, 6 and 7 in the example above. It is search for any file path that may (but is not required) start with "/", and contains "ckeditor/"
/ckeditor.*[\/]/i
This will match lines 1, 4, 6, 7 and 8. It is essentially saying that any file path that contains "ckeditor{any number of any characters other than newline}/" will work.