Merge branch 'source-paths-remapping'

Author: prantlf

README.md

@@ -144,6 +144,23 @@ module.exports = function(config) {
 };
 ```
 
+The code below shows a sample configuration of the preprocessor with source map loading only for files with the `sourceMappingURL` set. The default behaviour is trying to load source maps for all JavaScript files, also those without the `sourceMappingURL` set.
+
+```js
+// karma.conf.js
+module.exports = function(config) {
+  config.set({
+    plugins: ['karma-sourcemap-loader'],
+    preprocessors: {
+      '**/*.js': ['sourcemap']
+    },
+    sourceMapLoader: {
+      onlyWithURL: true
+    }
+  });
+};
+```
+
 The code below shows a sample configuration of the preprocessor with a strict error checking. A missing or an invalid source map will cause the test run fail.
 
 ```js

index.js

@@ -9,6 +9,7 @@ var createSourceMapLocatorPreprocessor = function(args, logger, config) {
   var remapPrefixes = options.remapPrefixes;
   var remapSource = options.remapSource;
   var useSourceRoot = options.useSourceRoot;
+  var onlyWithURL = options.onlyWithURL;
   var strict = options.strict;
   var needsUpdate = remapPrefixes || remapSource || useSourceRoot;
 
@@ -228,7 +229,11 @@ var createSourceMapLocatorPreprocessor = function(args, logger, config) {
     }
 
     if (!mapUrl) {
-      fileMap(file.path + ".map", true);
+      if (onlyWithURL) {
+        done(content);
+      } else {
+        fileMap(file.path + ".map", true);
+      }
     } else if (/^data:application\/json/.test(mapUrl)) {
       inlineMap(mapUrl.slice('data:application/json'.length));
     } else {

test/karma.source-root-value.js

@@ -3,7 +3,8 @@ const sharedConfig = require('./karma.shared');
 module.exports = function (config) {
   config.set(Object.assign({}, sharedConfig(config, 'test-source-root'), {
     sourceMapLoader: {
-      useSourceRoot: '/sources'
+      useSourceRoot: '/sources',
+      onlyWithURL: true // Just to complete the code coverage
     }
   }));
 };