➕ remap coverage to original source if it was transpiled

lib/hooks.js

@@ -0,0 +1,19 @@
+class Hooks {
+    constructor() {
+        this.hooks = [];
+    }
+
+    add(hook) {
+        this.hooks.push(hook);
+    }
+
+    clearAll() {
+        this.hooks = this.hooks.filter((hook) => {
+            hook();
+
+            return false;
+        });
+    }
+}
+
+export default new Hooks();

lib/instrument.js

@@ -1,4 +1,6 @@
-import { coverageVariable, addHook, clearHooks } from './utils';
+import coverageVariable from './variable';
+import hooks from './hooks';
+import remapper from './remapper';
 
 export default (options) => (input) => {
     return function istanbulInstrument(log) {
@@ -11,7 +13,8 @@ export default (options) => (input) => {
                 coverageVariable
             });
 
-            clearHooks();
+            hooks.clearAll();
+            remapper.createStore();
 
             const hook = hookRequire(
                 // hook requires matches input files
@@ -22,13 +25,14 @@ export default (options) => (input) => {
                 (source, file) => {
                     const result = instrumenter.instrumentSync(source, file);
 
+                    remapper.addSource(file, source);
                     log(file);
 
                     return result;
                 }
             );
 
-            addHook(hook);
+            hooks.add(hook);
             log('require() is hooked');
 
             resolve(input);

lib/remapper.js

@@ -0,0 +1,32 @@
+import { createSourceMapStore } from 'istanbul-lib-source-maps';
+import { fromSource as getSourceMapFromSource } from 'convert-source-map';
+
+const isLargeSource = true;
+
+class Remapper {
+    constructor() {
+        this.sourceMapStore = null;
+    }
+
+    createStore() {
+        this.sourceMapStore = createSourceMapStore();
+    }
+
+    addSource(file, source) {
+        const sourceMap = getSourceMapFromSource(source, isLargeSource);
+
+        if (sourceMap) {
+            this.sourceMapStore.registerMap(file, sourceMap.toObject());
+        }
+    }
+
+    remapCoverageMap(coverageMap) {
+        const transformedCoverage = this.sourceMapStore.transformCoverage(coverageMap);
+
+        if (transformedCoverage) {
+            return transformedCoverage.map;
+        }
+    }
+}
+
+export default new Remapper();

lib/report.js

@@ -1,25 +1,28 @@
-import { coverageVariable, clearHooks } from './utils';
+import coverageVariable from './variable';
+import hooks from './hooks';
+import remapper from './remapper';
 
 export default (formats = [ 'lcovonly', 'text-summary' ]) => (input) => {
     return function istanbulReport(log) {
-        const libCoverage = require('istanbul-lib-coverage');
+        const createCoverageMap = require('istanbul-lib-coverage').createCoverageMap;
         const createReporter = require('istanbul-api').createReporter;
 
         return new Promise((resolve, reject) => {
-            clearHooks();
+            hooks.clearAll();
 
             if (!global[coverageVariable]) {
                 return reject('no coverage information was collected');
             }
 
-            const coverageMap = libCoverage.createCoverageMap(global[coverageVariable]);
+            const coverageMap = createCoverageMap(global[coverageVariable]);
+            const remappedCoverageMap = remapper.remapCoverageMap(coverageMap);
             const reporter = createReporter();
 
             formats.forEach((format) => {
                 log(format);
 
                 reporter.add(format);
-                reporter.write(coverageMap);
+                reporter.write(remappedCoverageMap);
             });
 
             resolve(input);

lib/thresholds.js

@@ -1,21 +1,24 @@
-import { coverageVariable, clearHooks } from './utils';
+import coverageVariable from './variable';
+import hooks from './hooks';
+import remapper from './remapper';
 
 export default (options = {}) => (input) => {
     return function istanbulThresholds(/* log */) {
         const libCoverage = require('istanbul-lib-coverage');
 
         return new Promise((resolve, reject) => {
-            clearHooks();
+            hooks.clearAll();
 
             if (!global[coverageVariable]) {
                 return reject('no coverage information was collected');
             }
 
             const coverageMap = libCoverage.createCoverageMap(global[coverageVariable]);
+            const remappedCoverageMap = remapper.remapCoverageMap(coverageMap);
             const coverageSummary = libCoverage.createCoverageSummary();
 
-            coverageMap.files().forEach((file) => {
-                const fileCoverage = coverageMap.fileCoverageFor(file);
+            remappedCoverageMap.files().forEach((file) => {
+                const fileCoverage = remappedCoverageMap.fileCoverageFor(file);
                 const fileSummary = fileCoverage.toSummary();
 
                 coverageSummary.merge(fileSummary);

lib/variable.js

@@ -0,0 +1 @@
+export default '__start_istanbul__';

package.json

@@ -2,18 +2,27 @@
   "name": "start-istanbul",
   "version": "2.0.0",
   "description": "Istanbul tasks for Start",
-  "keywords": [ "start", "start-task", "istanbul", "coverage" ],
+  "keywords": [
+    "start",
+    "start-task",
+    "istanbul",
+    "coverage"
+  ],
   "homepage": "https://github.com/start-runner/istanbul",
   "repository": "start-runner/istanbul",
   "author": "Kir Belevich <kir@soulshine.in> (https://github.com/deepsweet)",
-  "files": [ "build/" ],
+  "files": [
+    "build/"
+  ],
   "main": "build/index.js",
   "dependencies": {
+    "babel-runtime": "^6.11.6",
+    "convert-source-map": "^1.3.0",
+    "istanbul-api": "^1.0.0-aplha.10",
+    "istanbul-lib-coverage": "^1.0.0",
     "istanbul-lib-hook": "^1.0.0-alpha.4",
     "istanbul-lib-instrument": "^1.1.0",
-    "istanbul-lib-coverage": "^1.0.0",
-    "istanbul-api": "^1.0.0-aplha.10",
-    "babel-runtime": "^6.11.6"
+    "istanbul-lib-source-maps": "^1.0.1"
   },
   "devDependencies": {
     "start-babel-cli": "^2.0.1",