# lib/goog/labs/testing/matcher.js

1 | // Copyright 2012 The Closure Library Authors. All Rights Reserved.
2 | //
3 | // Licensed under the Apache License, Version 2.0 (the "License");
4 | // you may not use this file except in compliance with the License.
5 | // You may obtain a copy of the License at
6 | //
7 | // http://www.apache.org/licenses/LICENSE-2.0
8 | //
9 | // Unless required by applicable law or agreed to in writing, software
10 | // distributed under the License is distributed on an "AS-IS" BASIS,
11 | // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 | // See the License for the specific language governing permissions and
13 | // limitations under the License.
14 |
15 | /**
16 | * @fileoverview Provides the base Matcher interface. User code should use the
17 | * matchers through assertThat statements and not directly.
18 | */
19 |
20 |
21 | goog.provide('goog.labs.testing.Matcher');
22 |
23 |
24 |
25 | /**
26 | * A matcher object to be used in assertThat statements.
27 | * @interface
28 | */
29 | goog.labs.testing.Matcher = function() {};
30 |
31 |
32 | /**
33 | * Determines whether a value matches the constraints of the match.
34 | *
35 | * @param {*} value The object to match.
36 | * @return {boolean} Whether the input value matches this matcher.
37 | */
38 | goog.labs.testing.Matcher.prototype.matches = function(value) {};
39 |
40 |
41 | /**
42 | * Describes why the matcher failed.
43 | *
44 | * @param {*} value The value that didn't match.
45 | * @param {string=} opt_description A partial description to which the reason
46 | * will be appended.
47 | *
48 | * @return {string} Description of why the matcher failed.
49 | */
50 | goog.labs.testing.Matcher.prototype.describe =
51 | function(value, opt_description) {};
52 |
53 |
54 | /**
55 | * Generates a Matcher from the ‘matches’ and ‘describe’ functions passed in.
56 | *
57 | * @param {!Function} matchesFunction The ‘matches’ function.
58 | * @param {Function=} opt_describeFunction The ‘describe’ function.
59 | * @return {!Function} The custom matcher.
60 | */
61 | goog.labs.testing.Matcher.makeMatcher =
62 | function(matchesFunction, opt_describeFunction) {
63 |
64 | /**
65 | * @constructor
66 | * @implements {goog.labs.testing.Matcher}
67 | * @final
68 | */
69 | var matcherConstructor = function() {};
70 |
71 | /** @override */
72 | matcherConstructor.prototype.matches = matchesFunction;
73 |
74 | if (opt_describeFunction) {
75 | /** @override */
76 | matcherConstructor.prototype.describe = opt_describeFunction;
77 | }
78 |
79 | return matcherConstructor;
80 | };