Font paths aren't remapped when building with lessc -ru

[ali1234]

To reproduce:

git clone git://github.com/twbs/bootstrap
echo '@import "bootstrap/less/bootstrap.less";' > my.less
lessc -ru my.less | grep fonts

Expected output:

  src: url('bootstrap/fonts/glyphicons-halflings-regular.eot');
  src: url('bootstrap/fonts/glyphicons-halflings-regular.eot?#iefix') format('embedded-opentype'), url('bootstrap/fonts/glyphicons-halflings-regular.woff') format('woff'), url('bootstrap/fonts/glyphicons-halflings-regular.ttf') format('truetype'), url('bootstrap/fonts/glyphicons-halflings-regular.svg#glyphicons_halflingsregular') format('svg');

Actual output:

  src: url('../fonts/glyphicons-halflings-regular.eot');
  src: url('../fonts/glyphicons-halflings-regular.eot?#iefix') format('embedded-opentype'), url('../fonts/glyphicons-halflings-regular.woff') format('woff'), url('../fonts/glyphicons-halflings-regular.ttf') format('truetype'), url('../fonts/glyphicons-halflings-regular.svg#glyphicons_halflingsregular') format('svg');

This happens because the src urls are escaped in glyphicons.less:

src: ~"url('@{icon-font-path}@{icon-font-name}.eot')";

Removing the ~"" escaping causes the correct relative URLs to be generated:

src: url('@{icon-font-path}@{icon-font-name}.eot');

This might be the cause of #13336

[ali1234]

This change was introduced in #10941 which appears to do the exact opposite of what it claims to do.

[ali1234]

For the next person to have this issue, the LESS workaround is to override icon-font-path immediately after importing bootstrap:

@import "bootstrap/less/bootstrap.less";
@icon-font-path: "bootstrap/fonts/";

[cvrebert]

The method for changing the icon font location has been documented per #13340.

[cvrebert]

Also, there's a bug in less.js: less/less.js#1821

[ali1234]

The documentation isn't sufficiently clear.

If you are placing the icon font files elsewhere or changing their filenames

I haven't moved any bootstrap files at all, so it isn't clear that this documentation applies to the issue, unless you already understand the issue (in which case you don't need the documentation!)

Also I cannot reproduce that less.js bug.

[cvrebert]

Fair point, I'll add that case to the docs.

[cvrebert]

Addressed by #13435.