lib/goog/labs/useragent/engine.js

1// Copyright 2013 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 Closure user agent detection.
17 * @see http://en.wikipedia.org/wiki/User_agent
18 * For more information on browser brand, platform, or device see the other
19 * sub-namespaces in goog.labs.userAgent (browser, platform, and device).
20 *
21 */
22
23goog.provide('goog.labs.userAgent.engine');
24
25goog.require('goog.array');
26goog.require('goog.labs.userAgent.util');
27goog.require('goog.string');
28
29
30/**
31 * @return {boolean} Whether the rendering engine is Presto.
32 */
33goog.labs.userAgent.engine.isPresto = function() {
34 return goog.labs.userAgent.util.matchUserAgent('Presto');
35};
36
37
38/**
39 * @return {boolean} Whether the rendering engine is Trident.
40 */
41goog.labs.userAgent.engine.isTrident = function() {
42 // IE only started including the Trident token in IE8.
43 return goog.labs.userAgent.util.matchUserAgent('Trident') ||
44 goog.labs.userAgent.util.matchUserAgent('MSIE');
45};
46
47
48/**
49 * @return {boolean} Whether the rendering engine is Edge.
50 */
51goog.labs.userAgent.engine.isEdge = function() {
52 return goog.labs.userAgent.util.matchUserAgent('Edge');
53};
54
55
56/**
57 * @return {boolean} Whether the rendering engine is WebKit.
58 */
59goog.labs.userAgent.engine.isWebKit = function() {
60 return goog.labs.userAgent.util.matchUserAgentIgnoreCase('WebKit') &&
61 !goog.labs.userAgent.engine.isEdge();
62};
63
64
65/**
66 * @return {boolean} Whether the rendering engine is Gecko.
67 */
68goog.labs.userAgent.engine.isGecko = function() {
69 return goog.labs.userAgent.util.matchUserAgent('Gecko') &&
70 !goog.labs.userAgent.engine.isWebKit() &&
71 !goog.labs.userAgent.engine.isTrident() &&
72 !goog.labs.userAgent.engine.isEdge();
73};
74
75
76/**
77 * @return {string} The rendering engine's version or empty string if version
78 * can't be determined.
79 */
80goog.labs.userAgent.engine.getVersion = function() {
81 var userAgentString = goog.labs.userAgent.util.getUserAgent();
82 if (userAgentString) {
83 var tuples = goog.labs.userAgent.util.extractVersionTuples(
84 userAgentString);
85
86 var engineTuple = goog.labs.userAgent.engine.getEngineTuple_(tuples);
87 if (engineTuple) {
88 // In Gecko, the version string is either in the browser info or the
89 // Firefox version. See Gecko user agent string reference:
90 // http://goo.gl/mULqa
91 if (engineTuple[0] == 'Gecko') {
92 return goog.labs.userAgent.engine.getVersionForKey_(
93 tuples, 'Firefox');
94 }
95
96 return engineTuple[1];
97 }
98
99 // MSIE has only one version identifier, and the Trident version is
100 // specified in the parenthetical. IE Edge is covered in the engine tuple
101 // detection.
102 var browserTuple = tuples[0];
103 var info;
104 if (browserTuple && (info = browserTuple[2])) {
105 var match = /Trident\/([^\s;]+)/.exec(info);
106 if (match) {
107 return match[1];
108 }
109 }
110 }
111 return '';
112};
113
114
115/**
116 * @param {!Array<!Array<string>>} tuples Extracted version tuples.
117 * @return {!Array<string>|undefined} The engine tuple or undefined if not
118 * found.
119 * @private
120 */
121goog.labs.userAgent.engine.getEngineTuple_ = function(tuples) {
122 if (!goog.labs.userAgent.engine.isEdge()) {
123 return tuples[1];
124 }
125 for (var i = 0; i < tuples.length; i++) {
126 var tuple = tuples[i];
127 if (tuple[0] == 'Edge') {
128 return tuple;
129 }
130 }
131};
132
133
134/**
135 * @param {string|number} version The version to check.
136 * @return {boolean} Whether the rendering engine version is higher or the same
137 * as the given version.
138 */
139goog.labs.userAgent.engine.isVersionOrHigher = function(version) {
140 return goog.string.compareVersions(goog.labs.userAgent.engine.getVersion(),
141 version) >= 0;
142};
143
144
145/**
146 * @param {!Array<!Array<string>>} tuples Version tuples.
147 * @param {string} key The key to look for.
148 * @return {string} The version string of the given key, if present.
149 * Otherwise, the empty string.
150 * @private
151 */
152goog.labs.userAgent.engine.getVersionForKey_ = function(tuples, key) {
153 // TODO(nnaze): Move to util if useful elsewhere.
154
155 var pair = goog.array.find(tuples, function(pair) {
156 return key == pair[0];
157 });
158
159 return pair && pair[1] || '';
160};