Support absolute file:// paths in sourceMappingURL

Hi! I’m working on https://github.com/mozilla/tofino and we have some interesting requirements. It appears that we need absolute file:// paths in our sourceMappingURL to support source maps in the (Chrome) devtools that Electron provides natively. That is, we want:

//# sourceMappingURL=file:///Users/nalexander/Mozilla/tofino/lib/main/browser.map

Unfortunately, that conflicts with source-map-support, which doesn’t appreciate absolute paths of this kind. Would you merge a patch to handle (in Node.js only) file:// protocols?

[nadako]

Same issue here with source maps generated by Haxe. Please fix 😃

[psulek]

I got same problems with electron and found maybe easy fix?

My webpacked bundled output js has this line on end: //# sourceMappingURL=appr.js.map which is relative path (just file name).

Problem seems to be in function:

function supportRelativeURL(file, url) {
  if (!file) return url;
  var dir = path.dirname(file);
  var match = /^\w+:\/\/[^\/]*/.exec(dir);
  var protocol = match ? match[0] : '';
  return protocol + path.resolve(dir.slice(protocol.length), url);
}

which incorrectly extract “protocol” information from file param when value is like file:///c:/dev/script1.js (local file protocol).

regex extract protocol value to file:// instead of file:/// (missing 3rd slash). It seems that problem is in this regex: var match = /^\w+:\/\/[^\/]*/.exec(dir);

And reason why param file has file:/// protocol: Electron loads html page in renderer process from file on disk, so function function wrapCallSite(frame) gets file:///c:/dev/script1.js on line: var source = frame.getFileName() || frame.getScriptNameOrSourceURL();

Possible fix will be to update regex on line var match = /^\w+:\/\/[^\/]*/.exec(dir); to correcly match http|s|file:/// protocols. Sorry i havent time now to do patch so if someone had time to do that it will be super.