Add string test filter (cf #68)

Author: ctjhoa

README.md

@@ -1080,6 +1080,14 @@ Repeats a string n times<br/>
 <!--repeat:
 foo-foo-foo
 ```
+###test
+Test if a string match a pattern<br/>
+**Usage:** ```string | test: pattern: flag[optional]```
+```html
+<p>{{ '15/12/2003' | test: '^[0-9]{2}[/]{1}[0-9]{2}[/]{1}[0-9]{4}$': 'i' }}</p>
+<!--result:
+true
+```
 #Math
 
 ###max

src/_filter/string/test.js

@@ -0,0 +1,20 @@
+/**
+ * @ngdoc filter
+ * @name test
+ * @kind function
+ *
+ * @description
+ * test if a string match a pattern.
+ */
+angular.module('a8m.test', [])
+
+  .filter('test', function () {
+    return function (input, pattern, flag) {
+
+      var reg = new RegExp(pattern, flag);
+
+      return isString(input)
+        ? reg.test(input)
+        : input;
+    }
+  });

src/filters.js

@@ -22,6 +22,7 @@ angular.module('angular.filter', [
   'a8m.ltrim',
   'a8m.rtrim',
   'a8m.repeat',
+  'a8m.test',
 
   'a8m.to-array',
   'a8m.concat',

test/spec/filter/string/test.js

@@ -0,0 +1,31 @@
+'use strict';
+
+describe('testFilter', function () {
+
+  var filter;
+
+  beforeEach(module('a8m.test'));
+
+  beforeEach(inject(function ($filter) {
+    filter = $filter('test');
+  }));
+
+  it('should test a string with given pattern', function() {
+
+    expect(filter('15/12/2003', '^[0-9]{2}[/]{1}[0-9]{2}[/]{1}[0-9]{4}$', 'i')).toEqual(true);
+    expect(filter('foobarbaz', '^[a-z]{3,}$')).toEqual(true);
+    expect(filter('FOOBARBAZ', '^[a-z]{3,}$', 'i')).toEqual(true);
+    expect(filter('FOOBARBAZ', '^[a-z]{3,}$')).toEqual(false);
+    expect(filter('foobarbaz', '\W')).toEqual(false);
+    expect(filter('1a/bb/2003', '^[0-9]{2}[/]{1}[0-9]{2}[/]{1}[0-9]{4}$', 'i')).toEqual(false);
+
+  });
+
+  it('should get a !string and not touch it', function() {
+    expect(filter({})).toEqual({});
+    expect(filter([])).toEqual([]);
+    expect(filter(1)).toEqual(1);
+    expect(filter(!1)).toBeFalsy();
+  });
+
+});