Add support for configurable file extensions

README.md

@@ -59,6 +59,23 @@ of the pre-transpiled code. You'll have to configure your custom require hook
 to inline the source map in the transpiled code. For Babel that means setting
 the `sourceMaps` option to `inline`.
 
+## Support For Custom File Extensions (.jsx, .es6)
+Supporting file extensions can be configured through either the configuration arguments or with the `nyc` config section in `package.json`.
+
+```shell
+nyc --extension .jsx --extension .es6 npm test
+```
+
+```json
+{"nyc": {
+  "extensions": [
+      ".jsx",
+      ".es6"
+    ]
+  }
+}
+```
+
 ## Checking Coverage
 
 nyc exposes istanbul's check-coverage tool. After running your tests with nyc,

bin/nyc.js

@@ -88,6 +88,11 @@ var yargs = require('yargs')
     type: 'boolean',
     describe: 'cache instrumentation results for improved performance'
   })
+  .options('e', {
+    alias: 'extension',
+    default: [],
+    describe: 'a list of extensions that nyc should handle in addition to .js'
+  })
   .option('check-coverage', {
     type: 'boolean',
     default: false,
@@ -128,6 +133,7 @@ if (argv._[0] === 'report') {
 } else if (argv._.length) {
   // wrap subprocesses and execute argv[1]
   if (!Array.isArray(argv.require)) argv.require = [argv.require]
+  if (!Array.isArray(argv.extension)) argv.extension = [argv.extension]
 
   var nyc = (new NYC({
     require: argv.require
@@ -143,6 +149,9 @@ if (argv._[0] === 'report') {
   if (argv.require.length) {
     env.NYC_REQUIRE = argv.require.join(',')
   }
+  if (argv.extension.length) {
+    env.NYC_EXTENSION = argv.extension.join(',')
+  }
   sw([wrapper], env)
 
   foreground(nyc.mungeArgs(argv), function (done) {

bin/wrap.js

@@ -8,6 +8,7 @@ try {
 
 ;(new NYC({
   require: process.env.NYC_REQUIRE ? process.env.NYC_REQUIRE.split(',') : [],
+  extension: process.env.NYC_EXTENSION ? process.env.NYC_EXTENSION.split(',') : [],
   enableCache: process.env.NYC_CACHE === 'enable'
 })).wrap()
 

index.js

@@ -17,6 +17,7 @@ var md5hex = require('md5-hex')
 var findCacheDir = require('find-cache-dir')
 var pkgUp = require('pkg-up')
 var readPkg = require('read-pkg')
+var js = require('default-require-extensions/js')
 
 /* istanbul ignore next */
 if (/index\.covered\.js$/.test(__filename)) {
@@ -53,7 +54,14 @@ function NYC (opts) {
   // require extensions can be provided as config in package.json.
   this.require = arrify(config.require || opts.require)
 
-  this.transform = this._createTransform()
+  this.extensions = arrify(config.extension || opts.extension).concat('.js').map(function (ext) {
+    return ext.toLowerCase()
+  })
+
+  this.transforms = this.extensions.reduce(function (transforms, ext) {
+    transforms[ext] = this._createTransform(ext)
+    return transforms
+  }.bind(this), {})
 
   this.sourceMapCache = new SourceMapCache()
 
@@ -79,7 +87,7 @@ NYC.prototype._loadConfig = function (opts) {
   return config
 }
 
-NYC.prototype._createTransform = function () {
+NYC.prototype._createTransform = function (ext) {
   var _this = this
   return cachingTransform({
     salt: JSON.stringify({
@@ -94,7 +102,7 @@ NYC.prototype._createTransform = function () {
     factory: this._transformFactory.bind(this),
     cacheDir: this.cacheDirectory,
     disableCache: !this.enableCache,
-    ext: '.js'
+    ext: ext
   })
 }
 
@@ -212,7 +220,15 @@ NYC.prototype._maybeInstrumentSource = function (code, filename, relFile) {
     return null
   }
 
-  return this.transform(code, {filename: filename, relFile: relFile})
+  var ext, transform
+  for (ext in this.transforms) {
+    if (filename.toLowerCase().substr(-ext.length) === ext) {
+      transform = this.transforms[ext]
+      break
+    }
+  }
+
+  return transform ? transform(code, {filename: filename, relFile: relFile}) : null
 }
 
 NYC.prototype._transformFactory = function (cacheDir) {
@@ -238,11 +254,17 @@ NYC.prototype._transformFactory = function (cacheDir) {
   }
 }
 
+NYC.prototype._handleJs = function (code, filename) {
+  var relFile = path.relative(this.cwd, filename)
+  return this._maybeInstrumentSource(code, filename, relFile) || code
+}
+
 NYC.prototype._wrapRequire = function () {
-  var _this = this
-  appendTransform(function (code, filename) {
-    var relFile = path.relative(_this.cwd, filename)
-    return _this._maybeInstrumentSource(code, filename, relFile) || code
+  var handleJs = this._handleJs.bind(this)
+
+  this.extensions.forEach(function (ext) {
+    require.extensions[ext] = js
+    appendTransform(handleJs, ext)
   })
 }
 

package.json

@@ -34,7 +34,8 @@
       "test/source-map-cache.js",
       "index.covered.js",
       "test/fixtures/_generateCoverage.js"
-    ]
+    ],
+    "extension": [".es6"]
   },
   "standard": {
     "ignore": [
@@ -65,6 +66,7 @@
     "arrify": "^1.0.1",
     "caching-transform": "^1.0.0",
     "convert-source-map": "^1.1.2",
+    "default-require-extensions": "^1.0.0",
     "find-cache-dir": "^0.1.1",
     "foreground-child": "^1.3.5",
     "glob": "^6.0.2",

test/fixtures/check-instrumented.es6

@@ -0,0 +1,7 @@
+function probe () {}
+
+// When instrumented there will be references to variables like
+// __cov_pwkoI2PYHp3LJXkn_erl1Q in the probe() source.
+module.exports = function () {
+  return /\b__cov_\B/.test(probe + '')
+}

test/fixtures/check-instrumented.foo.bar

@@ -0,0 +1,7 @@
+function probe () {}
+
+// When instrumented there will be references to variables like
+// __cov_pwkoI2PYHp3LJXkn_erl1Q in the probe() source.
+module.exports = function () {
+  return /\b__cov_\B/.test(probe + '')
+}

test/fixtures/package.json

@@ -12,7 +12,8 @@
       "exclude": [
         "**/blarg",
         "**/blerg"
-      ]
+      ],
+      "extension": [".es6", ".foo.BAR"]
     }
   }
 }

test/src/nyc-test.js

@@ -83,6 +83,22 @@ describe('nyc', function () {
 
       nyc.exclude.length.should.eql(19)
     })
+
+    it("loads 'extension' patterns from package.json#config.nyc", function () {
+      var nyc = new NYC({
+        cwd: path.resolve(__dirname, '../fixtures')
+      })
+
+      nyc.extensions.length.should.eql(3)
+    })
+
+    it("loads 'extension' from package.json#nyc", function () {
+      var nyc = new NYC({
+        cwd: path.resolve(__dirname, '../..')
+      })
+
+      nyc.extensions.length.should.eql(2)
+    })
   })
 
   describe('_prepGlobPatterns', function () {
@@ -232,6 +248,42 @@ describe('nyc', function () {
       })
     })
 
+    describe('compile handlers for custom extensions are assigned', function () {
+      it('assigns a function to custom extensions', function () {
+        var nyc = new NYC({
+          cwd: path.resolve(__dirname, '../fixtures')
+        })
+        nyc.reset()
+        nyc.wrap()
+
+        require.extensions['.es6'].should.be.a.function
+        require.extensions['.foo.bar'].should.be.a.function
+
+        // default should still exist
+        require.extensions['.js'].should.be.a.function
+      })
+
+      it('calls the `_handleJs` function for custom file extensions', function () {
+        // the `require` call to istanbul is deferred, loaded here so it doesn't mess with the hooks callCount
+        require('istanbul')
+
+        var nyc = new NYC({
+          cwd: path.resolve(__dirname, '../fixtures')
+        })
+
+        sinon.spy(nyc, '_handleJs')
+
+        nyc.reset()
+        nyc.wrap()
+
+        var check1 = require('../fixtures/check-instrumented.es6')
+        var check2 = require('../fixtures/check-instrumented.foo.bar')
+        check1().should.be.true
+        check2().should.be.true
+        nyc._handleJs.callCount.should.equal(2)
+      })
+    })
+
     function testSignal (signal, done) {
       var nyc = (new NYC({
         cwd: fixtures