Add tests for braille commands.

chrome/browser/resources/chromeos/chromevox/testing/mock_feedback.js

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+/**
+ * @fileoverview This file contains the |MockFeedback| class which is a
+ * combined mock class for speech and braille feedback.  A test that uses
+ * this class may add expectations for speech utterances and braille display
+ * content to be output.  The |install| method sets appropriate mock classes
+ * as the |cvox.ChromeVox.tts| and |cvox.ChromeVox.braille| objects,
+ * respectively.  Output sent to those objects will then be collected in
+ * an internal queue.
+ *
+ * Expectations can be added using the |expectSpeech| and |expectBraille|
+ * methods.  These methods take either strings or regular expressions to match
+ * against.  Strings must match a full utterance (or display content) exactly,
+ * while a regular expression must match a substring (use anchor operators if
+ * needed).
+ *
+ * Function calls may be inserted in the stream of expectations using the
+ * |call| method.  Such callbacks are called after all preceding expectations
+ * have been met, and before any further expectations are matched.  Callbacks
+ * are called in the order they were added to the mock.
+ *
+ * The |replay| method starts processing any pending utterances and braille
+ * display content and will try to match expectations as new feedback enters
+ * the queue asynchronously.  When all expectations have been met and callbacks
+ * called, the finish callback, if any was provided to the constructor, is
+ * called.
+ *
+ * This mock class is lean, meaning that feedback that doesn't match
+ * any expectations is silently ignored.
+ *
+ * NOTE: for asynchronous tests, the processing will never finish if there
+ * are unmet expectations.  To help debugging in such situations, the mock
+ * will output its pending state if there are pending expectations and no
+ * output is received within a few seconds.
+ *
+ * See mock_feedback_test.js for example usage of this class.
+ */
+
+/**
+ * Combined mock class for braille and speech output.
+ * @param {function=} opt_finishedCallback Called when all expectations have
+ *     been met.
+ * @constructor
+ */
+var MockFeedback = function(opt_finishedCallback) {
+  /**
+   * @type {function}
+   * @private
+   */
+  this.finishedCallback_ = opt_finishedCallback || null;
+  /**
+   * True when |replay| has been called and actions are being replayed.
+   * @type {boolean}
+   * @private
+   */
+  this.replaying_ = false;
+  /**
+   * True when inside the |process| function to prevent nested calls.
+   * @type {boolean}
+   * @private
+   */
+  this.inProcess_ = false;
+  /**
+   * Pending expectations and callbacks.
+   * @type {Array<{perform: function(): boolean, toString: function(): string}>}
+   * @private
+   */
+  this.pendingActions_ = [];
+  /**
+   * Pending speech utterances.
+   * @type {Array<{text: string, callback: (function|undefined)}>}
+   * @private
+   */
+  this.pendingUtterances_ = [];
+  /**
+   * Pending braille output.
+   * @type {Array<{text: string, callback: (function|undefined)}>}
+   * @private
+   */
+  this.pendingBraille_ = [];
+  /**
+   * Handle for the timeout set for debug logging.
+   * @type {number}
+   * @private
+   */
+  this.logTimeoutId_ = 0;
+  /**
+   * @type {cvox.NavBraille}
+   * @private
+   */
+  this.lastMatchedBraille_ = null;
+};
+
+MockFeedback.prototype = {
+
+  /**
+   * Install mock objects as |cvox.ChromeVox.tts| and |cvox.ChromeVox.braille|
+   * to collect feedback.
+   */
+  install: function() {
+    assertFalse(this.replaying_);
+
+    var MockTts = function() {};
+    MockTts.prototype = {
+      __proto__: cvox.TtsInterface.prototype,
+      speak: this.addUtterance_.bind(this)
+    };
+
+    cvox.ChromeVox.tts = new MockTts();
+
+    var MockBraille = function() {};
+    MockBraille.prototype = {
+      __proto__: cvox.BrailleInterface.prototype,
+      write: this.addBraille_.bind(this)
+    };
+
+    cvox.ChromeVox.braille = new MockBraille();
+  },
+
+  /**
+   * Adds an expectation for one or more spoken utterances.
+   * @param {...(string|RegExp)} var_args One or more utterance to add as
+   *     expectations.
+   * @return {MockFeedback} |this| for chaining
+   */
+  expectSpeech: function() {
+    assertFalse(this.replaying_);
+    Array.prototype.forEach.call(arguments, function(text) {
+      this.pendingActions_.push({
+        perform: function() {
+          return !!MockFeedback.matchAndConsume_(
+              text, {}, this.pendingUtterances_);
+        }.bind(this),
+        toString: function() { return 'Speak \'' + text + '\''; }
+      });
+    }.bind(this));
+    return this;
+  },
+
+  /**
+   * Adds an expectation for braille output.
+   * @param {string|RegExp} text
+   * @param {Object=} opt_props Additional properties to match in the
+   *     |NavBraille|
+   * @return {MockFeedback} |this| for chaining
+   */
+  expectBraille: function(text, opt_props) {
+    assertFalse(this.replaying_);
+    var props = opt_props || {};
+    this.pendingActions_.push({
+      perform: function() {
+        var match = MockFeedback.matchAndConsume_(
+            text, props, this.pendingBraille_);
+        if (match)
+          this.lastMatchedBraille_ = match;
+        return !!match;
+      }.bind(this),
+      toString: function() {
+        return 'Braille \'' + text + '\' ' + JSON.stringify(props);
+      }
+    });
+    return this;
+  },
+
+  /**
+   * Arranges for a callback to be invoked when all expectations that were
+   * added before this call have been met.  Callbacks are called in the
+   * order they are added.
+   * @param {Function} callback
+   * @return {MockFeedback} |this| for chaining
+   */
+  call: function(callback) {
+    assertFalse(this.replaying_);
+    this.pendingActions_.push({
+      perform: function() {
+        callback();
+        return true;
+      },
+      toString: function() {
+        return 'Callback';
+      }
+    });
+    return this;
+  },
+
+  /**
+   * Processes any feedback that has been received so far and treis to
+   * satisfy the registered expectations.  Any feedback that is received
+   * after this call (via the installed mock objects) is processed immediately.
+   * When all expectations are satisfied and registered callbacks called,
+   * the finish callbcak, if any, is called.
+   * This function may only be called once.
+   */
+  replay: function() {
+    assertFalse(this.replaying_);
+    this.replaying_ = true;
+    this.process_();
+  },
+
+  /**
+   * Returns the |NavBraille| that matched an expectation.  This is
+   * intended to be used by a callback to invoke braille commands that
+   * depend on display contents.
+   * @type {cvox.NavBraille}
+   */
+  get lastMatchedBraille() {
+    assertTrue(this.replaying_);
+    return this.lastMatchedBraille_;
+  },
+
+  /**
+   * @param {string} textString
+   * @param {cvox.QueueMode} queueMode
+   * @param {Object=} properties
+   * @private
+   */
+  addUtterance_: function(textString, queueMode, properties) {
+    var callback;
+    if (properties && (properties.startCallback || properties.endCallback)) {
+      var startCallback = properties.startCallback;
+      var endCallback = properties.endCallback;
+      callback = function() {
+        startCallback && startCallback();
+        endCallback && endCallback();
+      };
+    }
+    this.pendingUtterances_.push(
+        {text: textString,
+         callback: callback});
+    this.process_();
+  },
+
+  /** @private */
+  addBraille_: function(navBraille) {
+    this.pendingBraille_.push(navBraille);
+    this.process_();
+  },
+
+  /*** @private */
+  process_: function() {
+    if (!this.replaying_ || this.inProcess_)
+      return;
+    try {
+      this.inProcess_ = true;
+      while (this.pendingActions_.length > 0) {
+        var action = this.pendingActions_[0];
+        if (action.perform()) {
+          this.pendingActions_.shift();
+          if (this.logTimeoutId_) {
+            window.clearTimeout(this.logTimeoutId_);
+            this.logTimeoutId_ = 0;
+          }
+        } else {
+          break;
+        }
+      }
+      if (this.pendingActions_.length == 0) {
+        if (this.finishedCallback_) {
+          this.finishedCallback_();
+          this.finishedCallback_ = null;
+        }
+      } else {
+        // If there are pending actions and no matching feedback for a few
+        // seconds, log the pending state to ease debugging.
+        if (!this.logTimeoutId_) {
+          this.logTimeoutId_ = window.setTimeout(
+              this.logPendingState_.bind(this), 2000);
+        }
+      }
+    } finally {
+      this.inProcess_ = false;
+    }
+  },
+
+  /** @private */
+  logPendingState_: function() {
+    if (this.pendingActions_.length > 0)
+      console.log('Still waiting for ' + this.pendingActions_[0].toString());
+    function logPending(desc, list) {
+      if (list.length > 0)
+        console.log('Pending ' + desc + ':\n  ' +
+            list.map(function(i) {
+              var ret = '\'' + i.text + '\'';
+              if ('startIndex' in i)
+                ret += ' startIndex=' + i.startIndex;
+              if ('endIndex' in i)
+                ret += ' endIndex=' + i.endIndex;
+              return ret;
+            }).join('\n  ') + '\n  ');
+    }
+    logPending('speech utterances', this.pendingUtterances_);
+    logPending('braille', this.pendingBraille_);
+    this.logTimeoutId_ = 0;
+  },
+};
+
+/**
+ * @param {string} text
+ * @param {Object} props
+ * @param {Array<{text: (string|RegExp), callback: (function|undefined)}>}
+ *     pending
+ * @return {Object}
+ * @private
+ */
+MockFeedback.matchAndConsume_ = function(text, props, pending) {
+  for (var i = 0, candidate; candidate = pending[i]; ++i) {
+    var candidateText = candidate.text.toString();
+    if (text === candidateText ||
+        (text instanceof RegExp && text.test(candidateText))) {
+      var matched = true;
+      for (prop in props) {
+        if (candidate[prop] !== props[prop]) {
+          matched = false;
+          break;
+        }
+      }
+      if (matched)
+        break;
+    }
+  }
+  if (candidate) {
+    var consumed = pending.splice(0, i + 1);
+    consumed.forEach(function(item) {
+      if (item.callback)
+        item.callback();
+    });
+  }
+  return candidate;
+};