feat: add grep option like in karma-mocha

README.md

@@ -60,6 +60,27 @@ module.exports = function(config) {
 };
 ```
 
+If you want run only some tests matching a given pattern you can do this in the following way
+
+```bash
+karma start &
+karma run -- --grep=<pattern>
+```
+
+or
+
+```js
+module.exports = function(config) {
+  config.set({
+    ...
+    client: {
+      args: ['--grep', '<pattern>'],
+      ...
+    }
+  });
+};
+```
+
 ----
 
 For more information on Karma see the [homepage].

src/adapter.js

@@ -235,6 +235,67 @@ function KarmaReporter(tc, jasmineEnv) {
   };
 }
 
+/**
+ * Extract grep option from karma config
+ * @param {[Array|string]} clientArguments The karma client arguments
+ * @return {string} The value of grep option by default empty string
+ */
+var getGrepOption = function(clientArguments) {
+  var clientArgString = clientArguments || '';
+
+  if (Object.prototype.toString.call(clientArguments) === '[object Array]') {
+    clientArgString = clientArguments.join('=');
+  }
+
+  var match = /--grep=(.*)/.exec(clientArgString);
+  return match ? match[1] : '';
+};
+
+/**
+ * Extract grep option from karma config
+ * @param {[Array|string]} clientArguments The karma client arguments
+ * @return {string} The value of grep option by default empty string
+ */
+var getGrepOption = function(clientArguments) {
+  var clientArgString = clientArguments || '';
+
+  if (Object.prototype.toString.call(clientArguments) === '[object Array]') {
+    clientArgString = clientArguments.join('=');
+  }
+
+  var match = /--grep=(.*)/.exec(clientArgString);
+  return match ? match[1] : '';
+};
+
+/**
+ * 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);
+
+  this.matches = function(specName) {
+    return filterPattern.test(specName);
+  };
+};
+
+/**
+ * @param {Object} config The karma config
+ * @param {Object} jasmineEnv jasmine environment object
+ */
+var createSpecFilter = function(config, jasmineEnv) {
+  var specFilter = new KarmaSpecFilter({
+    filterString: function() {
+      return getGrepOption(config.args);
+    }
+  });
+
+  jasmineEnv.specFilter = function(spec) {
+    return specFilter.matches(spec.getFullName());
+  };
+};
+
 /**
  * Karma starter function factory.
  *

src/adapter.wrapper

@@ -3,6 +3,7 @@
 %CONTENT%
 
 
+createSpecFilter(window.__karma__.config, jasmine.getEnv());
 window.__karma__.start = createStartFn(window.__karma__);
 
 })(window);

test/adapter.spec.js

@@ -2,6 +2,8 @@
  Tests for adapter/jasmine.js
  These tests are executed in browser.
  */
+/*global getJasmineRequireObj,jasmineRequire,MockSocket,KarmaReporter*/
+/*global formatFailedStep,indexOf,createStartFn,getGrepOption,KarmaSpecFilter,createSpecFilter*/
 
 /* jshint globalstrict: true */
 'use strict';
@@ -158,7 +160,7 @@ describe('jasmine adapter', function(){
       var counter = 3;
 
       spyOn(Date.prototype, 'getTime').andCallFake(function(){
-        return counter++;
+        return counter+=1;
       });
 
       karma.result.andCallFake(function(result){
@@ -259,4 +261,56 @@ describe('jasmine adapter', function(){
   });
 
 
+  describe('getGrepOption', function() {
+    it('should get grep option from config if args is array', function() {
+      expect(getGrepOption(['--grep', 'test'])).toEqual('test');
+    });
+
+    it('should return empty string if args does not contain grep option', function() {
+      expect(getGrepOption([])).toEqual('');
+    });
+
+    it('should get grep option from args if args is string', function() {
+      expect(getGrepOption('--grep=test')).toEqual('test');
+    });
+  });
+
+
+  describe('KarmaSpecFilter', 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('createSpecFilter', function() {
+    it('should create spec filter in jasmine', function() {
+      var jasmineEnvMock = {};
+      var karmaConfMock = {
+        args: ['--grep', 'test']
+      };
+      var specMock = {
+        getFullName: jasmine.createSpy('getFullName').andReturn('test')
+      };
+
+      createSpecFilter(karmaConfMock, jasmineEnvMock);
+
+      expect(jasmineEnvMock.specFilter(specMock)).toEqual(true);
+    });
+  });
 });