--grep option now supports real regular expressions but not masks onl…

…y. (#204)

To use real regular expressions, use the traditional JavaScript syntax:
> karma run -- --grep=/<regex>/<flags>
Sample:
> karma run -- --grep=/.*should.*/i

This implementation only extends the functionality without breaking the existing syntax.
You can continue to use the old syntax:
> karma run -- --grep=RootTestSuite

src/adapter.js

@@ -291,13 +291,30 @@ var getGrepOption = function (clientArguments) {
   }
 }
 
+var createRegExp = function (filter) {
+  filter = filter || ''
+  if (filter === '') {
+    return new RegExp() // to match all
+  }
+
+  var regExp = /^[/](.*)[/]([gmixXsuUAJD]*)$/ // pattern to check whether the string is RegExp pattern
+
+  var parts = regExp.exec(filter)
+  if (parts === null) {
+    return new RegExp(filter.replace(/[-[\]{}()*+?.,\\^$|#\s]/g, '\\$&')) // escape functional symbols
+  }
+
+  var patternExpression = parts[1]
+  var patternSwitches = parts[2]
+  return new RegExp(patternExpression, patternSwitches)
+}
+
 /**
  * Create jasmine spec filter
  * @param {Object} options Spec filter options
  */
 var KarmaSpecFilter = function (options) {
-  var filterString = options && options.filterString() && options.filterString().replace(/[-[\]{}()*+?.,\\^$|#\s]/g, '\\$&')
-  var filterPattern = new RegExp(filterString)
+  var filterPattern = createRegExp(options && options.filterString())
 
   this.matches = function (specName) {
     return filterPattern.test(specName)

test/adapter.spec.js

@@ -3,7 +3,7 @@
  These tests are executed in browser.
  */
 /* global getJasmineRequireObj, jasmineRequire, MockSocket, KarmaReporter */
-/* global formatFailedStep, , createStartFn, getGrepOption, KarmaSpecFilter, createSpecFilter */
+/* global formatFailedStep, , createStartFn, getGrepOption, createRegExp, KarmaSpecFilter, createSpecFilter */
 /* global getRelevantStackFrom: true, isExternalStackEntry: true */
 
 'use strict'
@@ -495,7 +495,72 @@ describe('jasmine adapter', function () {
     })
   })
 
-  describe('KarmaSpecFilter', function () {
+  describe('createRegExp', function () {
+    it('should match all string by null pattern', function () {
+      var regExp = createRegExp(null)
+
+      expect(regExp.test(null)).toEqual(true)
+      expect(regExp.test('bar')).toEqual(true)
+      expect(regExp.test('test')).toEqual(true)
+      expect(regExp.test('test.asfsdf.sdfgfdh')).toEqual(true)
+    })
+
+    it('should match all string by empty pattern', function () {
+      var regExp = createRegExp('')
+
+      expect(regExp.test(null)).toEqual(true)
+      expect(regExp.test('bar')).toEqual(true)
+      expect(regExp.test('test')).toEqual(true)
+      expect(regExp.test('test.asfsdf.sdfgfdh')).toEqual(true)
+    })
+
+    it('should match strings by pattern with flags', function () {
+      var regExp = createRegExp('/test.*/i')
+      expect(regExp.test(null)).toEqual(false)
+      expect(regExp.test('bar')).toEqual(false)
+      expect(regExp.test('test')).toEqual(true)
+      expect(regExp.test('test.asfsdf.sdfgfdh')).toEqual(true)
+    })
+
+    it('should match strings by pattern without flags', function () {
+      var regExp = createRegExp('/test.*/')
+      expect(regExp.test(null)).toEqual(false)
+      expect(regExp.test('bar')).toEqual(false)
+      expect(regExp.test('test')).toEqual(true)
+      expect(regExp.test('test.asfsdf.sdfgfdh')).toEqual(true)
+    })
+
+    it('should match strings by complex pattern', function () {
+      var regExp = createRegExp('/test.*[/]i/i')
+      expect(regExp.test(null)).toEqual(false)
+      expect(regExp.test('bar')).toEqual(false)
+      expect(regExp.test('test')).toEqual(false)
+      expect(regExp.test('test/i')).toEqual(true)
+    })
+  })
+
+  describe('KarmaSpecFilter(RegExp)', function () {
+    var specFilter
+
+    beforeEach(function () {
+      specFilter = new KarmaSpecFilter({
+        filterString: function () {
+          return '/test.*/'
+        }
+      })
+    })
+
+    it('should create spec filter', function () {
+      expect(specFilter).toBeDefined()
+    })
+
+    it('should filter spec by name', function () {
+      expect(specFilter.matches('bar')).toEqual(false)
+      expect(specFilter.matches('test')).toEqual(true)
+    })
+  })
+
+  describe('KarmaSpecFilter(non-RegExp)', function () {
     var specFilter
 
     beforeEach(function () {