chore(code coverage): remap multi staged commonjs sourcemap into orig…

…inal typescript code

closes ReactiveX#558

.travis.yml

@@ -20,5 +20,4 @@ script:
   - npm run build_cover
 
 after_script:
-  - ./node_modules/.bin/remap-istanbul -i coverage/coverage.json -o coverage/coverage-remapped.json && ./node_modules/.bin/remap-istanbul -i coverage/coverage.json -o coverage/coverage-remapped.lcov -t lcovonly && ./node_modules/.bin/remap-istanbul -i coverage/coverage.json -o coverage/coverage-remapped -t html
   - cat ./coverage/coverage-remapped.lcov  | ./node_modules/coveralls/bin/coveralls.js

lib/stage_sourcemap.js

@@ -0,0 +1,22 @@
+var fs = require('fs-extra');
+var glob = require('glob');
+var jsonfile = require('jsonfile');
+var transfer = require('multi-stage-sourcemap').transfer;
+
+glob('dist/es6/**/*.js.map', null, function (er, files) {
+  files.forEach(function (file) {
+    var source = jsonfile.readFileSync(file);
+    var destFile = file.replace('es6', 'cjs');
+    var dest = jsonfile.readFileSync(destFile);
+
+    var transferred = transfer({ fromSourceMap: JSON.stringify(dest),
+      toSourceMap: JSON.stringify(source) });
+
+    fs.unlink(destFile);
+    jsonfile.writeFile(destFile, transferred, function (err) {
+      if (err) {
+        console.log(err);
+      }
+    });
+  });
+});

package.json

@@ -18,7 +18,8 @@
     "lint_spec": "eslint spec/**/*.js --fix",
     "lint_src": "tslint -c .tslintrc src/**/*.ts",
     "lint": "npm run lint_src && npm run lint_spec && npm run lint_perf",
-    "cover": "istanbul cover -x \"*-spec.js index.js *-helper.js\" jasmine",
+    "cover": "istanbul cover -x \"*-spec.js index.js *-helper.js\" jasmine && npm run cover_remapping",
+    "cover_remapping": "node lib/stage_sourcemap.js && remap-istanbul -i coverage/coverage.json -o coverage/coverage-remapped.json && remap-istanbul -i coverage/coverage.json -o coverage/coverage-remapped.lcov -t lcovonly && remap-istanbul -i coverage/coverage.json -o coverage/coverage-remapped -t html",
     "test": "jasmine",
     "watch": "watch \"echo triggering build && npm run build_test && echo build completed\" src -d -u -w=15",
     "perf": "protractor protractor.conf.js",
@@ -82,7 +83,9 @@
     "istanbul": "0.3.22",
     "jasmine": "2.3.2",
     "jasmine-core": "2.3.4",
+    "jsonfile": "2.2.2",
     "lodash": "3.5.0",
+    "multi-stage-sourcemap": "0.2.1",
     "platform": "1.3.0",
     "promise": "7.0.3",
     "protractor": "2.2.0",