remove sourceMappingURL if it doesn't have the same name with the js …

[maxvoltage]

• vendor.js file can have multiple sourceMappingURL locations when modules have their own sourceMappingURL. source-map-url module finds only one sourceMappingURL at a time. This PR removes sourceMappingURL if it doesn't have the same name with the js file until it finds the correct one.

• Use the last map file if there is no map file with the same name with the js file. This is possibly wrong and it might rather be correct to raise an error in such case.

Related issue: ember-cli/ember-cli-terser#29

[ashleysommer]

This commit has a logic error.
The lastUrl variable actually stores the first found sourceMappingURL.
The variable is never updated during the loop.
If no matching filename is found in the file, it uses lastUrl, which still contains the first found sourceMappingURL.
I believe the intention was for lastUrl to be updating during the loop so it always contains the last found sourceMappingURL, so it can fallback to correctly to the last one when if a correct one is not found.

[ashleysommer]

This is the correct logic:

  let url = srcURL.getFrom(src);
  let lastUrl = srcURL.getFrom(src);
  // Make sure vendor.map is being used because vendor.js can have multiple sourceMappingURL if modules also have it.
  while (url && url.match(/.+?(?=\.map$)/)[0] !== relativePath.match(/(.*\/)?(.+)\.js/)[2]) {
    src = srcURL.removeFrom(src);
    lastUrl = url;    
    url = srcURL.getFrom(src);
  }
  // If there is no map url which has an identical name with the js file, use the last one.
  // It's possible we should rather raise an error instead.
  if (!url) {
    url = lastUrl;
  }

[maxvoltage]

thanks @ashleysommer , you understood my intention correctly. I will update the PR.

[stefanpenner]

just a heads-up, tests will be required

[Turbo87]

@maxvoltage sorry, I don't understand what problem exactly this PR is trying to fix. #55 should have fixed most of the issues. please make sure you're using the current version of this dependency.

[ashleysommer]

@Turbo87

#55 fix only applies when there is a single sourceMappingURL in the src file. It simply reads the directive, checks if the file exists, and ignores the sourceMap if it doesn't exist. It doesn't check for other sourceMappingURL directives in the src.

This fix applies in the case that there are two or more sourceMappingURL directives in the src (usually caused by concatenating multiple third-party libraries into a single vendor.js file).

This fix asserts that the most likely correct sourceMappingURL will be the one that matches/contains the filename of the src file.

Failing that, it falls back to using the last found sourceMappingURL, because the spec indicates that the correct sourceMappingURL should be at the end of the src file, and any before that must be artifacts from concatenation.