host/chrome/braille_input_handler_test.unitjs

// Copyright 2014 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.

// Include test fixture.
GEN_INCLUDE(['../../testing/chromevox_unittest_base.js']);

GEN_INCLUDE(['../../testing/fake_objects.js']);

// Fake out the Chrome API namespace we depend on.
var chrome = {};
/** Fake chrome.runtime object. */
chrome.runtime = {};
/** Fake chrome.virtualKeyboardPrivate object. */
chrome.virtualKeyboardPrivate = {};


/**
 * A fake input field that behaves like the Braille IME and also updates
 * the input manager's knowledge about the display content when text changes
 * in the edit field.
 * @param {FakePort} port A fake port.
 * @param {cvox.BrailleInputHandler} inputHandler to work with.
 * @constructor
 */
function FakeEditor(port, inputHandler) {
  /** @private {FakePort} */
  this.port_ = port;
  /** @private {cvox.BrailleInputHandler} */
  this.inputHandler_ = inputHandler;
  /** @private {string} */
  this.text_ = '';
  /** @private {number} */
  this.selectionStart_ = 0;
  /** @private {number} */
  this.selectionEnd_ = 0;
  /** @private {number} */
  this.contextID_ = 0;
  /** @private {boolean} */
  this.allowDeletes_ = false;
  port.postMessage = goog.bind(this.handleMessage_, this);
}


/**
 * Sets the content and selection (or cursor) of the edit field.
 * This fakes what happens when the field is edited by other means than
 * via the braille keyboard.
 * @param {string} text Text to replace the current content of the field.
 * @param {number} selectionStart Start of the selection or cursor position.
 * @param {number=} opt_selectionEnd End of selection, or ommited if the
 *     selection is a cursor.
 */
FakeEditor.prototype.setContent = function(
    text, selectionStart, opt_selectionEnd) {
  this.text_ = text;
  this.selectionStart_ = selectionStart;
  this.selectionEnd_ = goog.isDef(opt_selectionEnd) ?
      opt_selectionEnd : selectionStart;
  this.callOnDisplayContentChanged_();
};


/**
 * Sets the selection in the editor.
 * @param {number} selectionStart Start of the selection or cursor position.
 * @param {number=} opt_selectionEnd End of selection, or ommited if the
 *     selection is a cursor.
 */
FakeEditor.prototype.select = function(selectionStart, opt_selectionEnd) {
  this.setContent(this.text_, selectionStart, opt_selectionEnd);
};


/**
 * Inserts text into the edit field, optionally selecting the inserted
 * text.
 * @param {string} newText Text to insert.
 * @param {boolean=} opt_select If {@code true}, selects the inserted text,
 *     otherwise leaves the cursor at the end of the new text.
 */
FakeEditor.prototype.insert = function(newText, opt_select) {
  this.text_ =
      this.text_.substring(0, this.selectionStart_) +
      newText +
      this.text_.substring(this.selectionEnd_);
  if (opt_select) {
    this.selectionEnd_ = this.selectionStart_ + newText.length;
  } else {
    this.selectionStart_ += newText.length;
    this.selectionEnd_ = this.selectionStart_;
  }
  this.callOnDisplayContentChanged_();
};


/**
 * Sets whether the editor should cause a test failure if the input handler
 * tries to delete text before the cursor.  By default, thi value is
 * {@code false}.
 * @param {boolean} allowDeletes The new value.
 */
FakeEditor.prototype.setAllowDeletes = function(allowDeletes) {
  this.allowDeletes_ = allowDeletes;
};


/**
 * Signals to the input handler that the Braille IME is active or not active,
 * depending on the argument.
 * @param {boolean} value Whether the IME is active or not.
 */
FakeEditor.prototype.setActive = function(value) {
  this.message_({type: 'activeState', active: value});
};


/**
 * Fails if the current editor content and selection range don't match
 * the arguments to this function.
 * @param {string} text Text that should be in the field.
 * @param {number} selectionStart Start of selection.
 * @param {number+} opt_selectionEnd End of selection, default to selection
 *     start to indicate a cursor.
 */
FakeEditor.prototype.assertContentIs = function(
    text, selectionStart, opt_selectionEnd) {
  var selectionEnd = goog.isDef(opt_selectionEnd) ? opt_selectionEnd :
      selectionStart;
  assertEquals(text, this.text_);
  assertEquals(selectionStart, this.selectionStart_);
  assertEquals(selectionEnd, this.selectionEnd_);
};


/**
 * Sends a message from the IME to the input handler.
 * @param {Object} msg The message to send.
 * @private
 */
FakeEditor.prototype.message_ = function(msg) {
  var listener = this.port_.onMessage.getListener();
  assertNotEquals(null, listener);
  listener(msg);
};


/**
 * Calls the {@code onDisplayContentChanged} method of the input handler
 * with the current editor content and selection.
 * @private
 */
FakeEditor.prototype.callOnDisplayContentChanged_ = function() {
  this.inputHandler_.onDisplayContentChanged(
      cvox.BrailleUtil.createValue(
          this.text_, this.selectionStart_, this.selectionEnd_));
};


/**
 * Informs the input handler that a new text field is focused.  The content
 * of the field is not cleared and should be updated separately.
 * @param {string} fieldType The type of the field (see the documentation
 *     for the {@code chrome.input.ime} API).
 */
FakeEditor.prototype.focus = function(fieldType) {
  this.contextID_++;
  this.message_({type: 'inputContext',
                 context: {type: fieldType,
                           contextID: this.contextID_}});
};


/**
 * Inform the input handler that focus left the input field.
 */
FakeEditor.prototype.blur = function() {
  this.message_({type: 'inputContext', context: null});
  this.contextID_ = 0;
};


/**
 * Handles a message from the input handler to the IME.
 * @param {Object} msg The message.
 * @private
 */
FakeEditor.prototype.handleMessage_ = function(msg) {
  assertEquals('replaceText', msg.type);
  assertEquals(this.contextID_, msg.contextID);
  var deleteBefore = msg.deleteBefore;
  var newText = msg.newText;
  assertTrue(goog.isNumber(deleteBefore));
  assertTrue(goog.isString(newText));
  assertTrue(deleteBefore <= this.selectionStart_);
  if (deleteBefore > 0) {
    assertTrue(this.allowDeletes_);
    this.text_ =
        this.text_.substring(0, this.selectionStart_ - deleteBefore) +
        this.text_.substring(this.selectionEnd_);
    this.selectionStart_ -= deleteBefore;
    this.selectionEnd_ = this.selectionStart_;
    this.callOnDisplayContentChanged_();
  }
  this.insert(newText);
};

/*
 * Fakes a {@code Port} used for message passing in the Chrome extension APIs.
 * @constructor
 */
function FakePort() {
  /** @type {FakeChromeEvent} */
  this.onDisconnect = new FakeChromeEvent();
  /** @type {FakeChromeEvent} */
  this.onMessage = new FakeChromeEvent();
  /** @type {string} */
  this.name = cvox.BrailleInputHandler.IME_PORT_NAME_;
  /** @type {{id: string}} */
  this.sender = {id: cvox.BrailleInputHandler.IME_EXTENSION_ID_};
}

/**
 * Mapping from braille cells to Unicode characters.
 * @const Array.<Array.<string> >
 */
var UNCONTRACTED_TABLE = [
  ['0', ' '],
  ['1', 'a'], ['12', 'b'], ['14', 'c'], ['145', 'd'], ['15', 'e'],
  ['124', 'f'], ['1245', 'g'], ['125', 'h'], ['24', 'i'], ['245', 'j'],
  ['13', 'k'], ['123', 'l'], ['134', 'm'], ['1345', 'n'], ['135', 'o'],
  ['1234', 'p'], ['12345', 'q'], ['1235', 'r'], ['234', 's'], ['2345', 't']
];


/**
 * Mapping of braille cells to the corresponding word in Grade 2 US English
 * braille.  This table also includes the uncontracted table above.
 * If a match 'pattern' starts with '^', it must be at the beginning of
 * the string or be preceded by a blank cell.  Similarly, '$' at the end
 * of a 'pattern' means that the match must be at the end of the string
 * or be followed by a blank cell.  Note that order is significant in the
 * table.  First match wins.
 * @const
 */
var CONTRACTED_TABLE = [
  ['12 1235 123', 'braille'],
  ['^12$', 'but'],
  ['1456', 'this']].concat(UNCONTRACTED_TABLE);

/**
 * A fake braille translator that can do back translation according
 * to one of the tables above.
 * @param {Array.<Array.<number>>} table Backtranslation mapping.
 * @param {boolean=} opt_capitalize Whether the result should be capitalized.
 * @constructor
 */
function FakeTranslator(table, opt_capitalize) {
  /** @private */
  this.table_ = table.map(function(entry) {
    var cells = entry[0];
    var result = [];
    if (cells[0] === '^') {
      result.start = true;
      cells = cells.substring(1);
    }
    if (cells[cells.length - 1] === '$') {
      result.end = true;
      cells = cells.substring(0, cells.length - 1);
    }
    result[0] = cellsToArray(cells);
    result[1] = entry[1];
    return result;
  });
  /** @private {boolean} */
  this.capitalize_ = opt_capitalize || false;
}


/**
 * Implements the {@code cvox.LibLouis.BrailleTranslator.backTranslate} method.
 * @param {!ArrayBuffer} cells Cells to be translated.
 * @param {function(?string)} callback Callback for result.
 */
FakeTranslator.prototype.backTranslate = function(cells, callback) {
  var cellsArray = new Uint8Array(cells);
  var result = '';
  var pos = 0;
  while (pos < cellsArray.length) {
    var match = null;
    outer: for (var i = 0, entry; entry = this.table_[i]; ++i) {
      if (pos + entry[0].length > cellsArray.length) {
        continue;
      }
      if (entry.start && pos > 0 && cellsArray[pos - 1] !== 0) {
        continue;
      }
      for (var j = 0; j < entry[0].length; ++j) {
        if (entry[0][j] !== cellsArray[pos + j]) {
          continue outer;
        }
      }
      if (entry.end && pos + j < cellsArray.length &&
          cellsArray[pos + j] !== 0) {
        continue;
      }
      match = entry;
      break;
    }
    assertNotEquals(
        null, match,
        'Backtranslating ' + cellsArray[pos] + ' at ' + pos);
    result += match[1];
    pos += match[0].length;
  }
  if (this.capitalize_) {
    result = result.toUpperCase();
  }
  callback(result);
};

/**
 * Converts a list of cells, represented as a string, to an array.
 * @param {string} cells A string with space separated groups of digits.
 *     Each group corresponds to one braille cell and each digit in a group
 *     corresponds to a particular dot in the cell (1 to 8).  As a special
 *     case, the digit 0 by itself represents a blank cell.
 * @return {Array.<number>} An array with each cell encoded as a bit
 *     pattern (dot 1 uses bit 0, etc).
 */
function cellsToArray(cells) {
  return cells.split(/\s+/).map(function(cellString) {
    var cell = 0;
    assertTrue(cellString.length > 0);
    if (cellString != '0') {
      for (var i = 0; i < cellString.length; ++i) {
        var dot = cellString.charCodeAt(i) - '0'.charCodeAt(0);
        assertTrue(dot >= 1);
        assertTrue(dot <= 8);
        cell |= 1 << (dot - 1);
      }
    }
    return cell;
  });
}

/**
 * Test fixture.
 * @constructor
 * @extends {ChromeVoxUnitTestBase}
 */
function CvoxBrailleInputHandlerUnitTest() {}

CvoxBrailleInputHandlerUnitTest.prototype = {
  __proto__: ChromeVoxUnitTestBase.prototype,

  /** @override */
  closureModuleDeps: [
    'cvox.BrailleInputHandler',
    'cvox.BrailleUtil',
    'cvox.Spannable',
  ],

  /**
   * Creates an editor and establishes a connection from the IME.
   * @return {FakeEditor}
   */
  createEditor: function() {
    chrome.runtime.onConnectExternal.getListener()(this.port);
    return new FakeEditor(this.port, this.inputHandler);
  },

  /**
   * Sends a series of braille cells to the input handler.
   * @param {string} cells Braille cells, encoded as described in
   *     {@code cellsToArray}.
   * @return {boolean} {@code true} iff all cells were sent successfully.
   */
  sendCells: function(cells) {
    return cellsToArray(cells).reduce(function(prevResult, cell) {
      var event = {command: cvox.BrailleKeyCommand.DOTS, brailleDots: cell};
      return prevResult && this.inputHandler.onBrailleKeyEvent(event);
    }.bind(this), true);
  },

  /**
   * Sends a standard key event (such as backspace) to the braille input
   * handler.
   * @param {string} keyCode The key code name.
   * @return {boolean} Whether the event was handled.
   */
  sendKeyEvent: function(keyCode) {
    var event = {command: cvox.BrailleKeyCommand.STANDARD_KEY,
                 standardKeyCode: keyCode};
    return this.inputHandler.onBrailleKeyEvent(event);
  },

  /**
   * Shortcut for asserting that the value expansion mode is {@code NONE}.
   */
  assertExpandingNone: function() {
    assertEquals(cvox.ExpandingBrailleTranslator.ExpansionType.NONE,
                 this.inputHandler.getExpansionType());
  },

  /**
   * Shortcut for asserting that the value expansion mode is {@code SELECTION}.
   */
  assertExpandingSelection: function() {
    assertEquals(cvox.ExpandingBrailleTranslator.ExpansionType.SELECTION,
                 this.inputHandler.getExpansionType());
  },

  /**
   * Shortcut for asserting that the value expansion mode is {@code ALL}.
   */
  assertExpandingAll: function() {
    assertEquals(cvox.ExpandingBrailleTranslator.ExpansionType.ALL,
                 this.inputHandler.getExpansionType());
  },

  storeKeyEvent: function(event, opt_callback) {
    var storedCopy = {keyCode: event.keyCode, keyName: event.keyName,
                      charValue: event.charValue};
    if (event.type == 'keydown') {
      this.keyEvents.push(storedCopy);
    } else {
      assertEquals('keyup', event.type);
      assertTrue(this.keyEvents.length > 0);
      assertEqualsJSON(storedCopy, this.keyEvents[this.keyEvents.length - 1]);
    }
    if (goog.isDef(opt_callback)) {
      callback();
    }
  },

  /** @override */
  setUp: function() {
    chrome.runtime.onConnectExternal = new FakeChromeEvent();
    this.port = new FakePort();
    this.inputHandler = new cvox.BrailleInputHandler();
    this.inputHandler.init();
    this.uncontractedTranslator = new FakeTranslator(UNCONTRACTED_TABLE);
    this.contractedTranslator = new FakeTranslator(CONTRACTED_TABLE, true);
    chrome.virtualKeyboardPrivate.sendKeyEvent =
      this.storeKeyEvent.bind(this);
    this.keyEvents = [];
  }
};

TEST_F('CvoxBrailleInputHandlerUnitTest', 'ConnectFromUnknownExtension',
  function() {
  this.port.sender.id = 'your unknown friend';
  chrome.runtime.onConnectExternal.getListener()(this.port);
  this.port.onMessage.assertNoListener();
});


TEST_F('CvoxBrailleInputHandlerUnitTest', 'NoTranslator', function() {
  var editor = this.createEditor();
  editor.setContent('blah', 0);
  editor.setActive(true);
  editor.focus('email');
  assertFalse(this.sendCells('145 135 125'));
  editor.setActive(false);
  editor.blur();
  editor.assertContentIs('blah', 0);
});


TEST_F('CvoxBrailleInputHandlerUnitTest', 'InputUncontracted', function() {
  this.inputHandler.setTranslator(this.uncontractedTranslator);
  var editor = this.createEditor();
  editor.setActive(true);

  // Focus and type in a text field.
  editor.focus('text');
  assertTrue(this.sendCells('125 15 123 123 135'));  // hello
  editor.assertContentIs('hello', 'hello'.length);
  this.assertExpandingNone();

  // Move the cursor and type in the middle.
  editor.select(2);
  assertTrue(this.sendCells('0 2345 125 15 1235 15 0'));  // ' there '
  editor.assertContentIs('he there llo', 'he there '.length);

  // Field changes by some other means.
  editor.insert('you!');
  // Then type on the braille keyboard again.
  assertTrue(this.sendCells('0 125 15'));  // ' he'
  editor.assertContentIs('he there you! hello', 'he there you! he'.length);

  editor.blur();
  editor.setActive(false);
});


TEST_F('CvoxBrailleInputHandlerUnitTest', 'InputContracted', function() {
  var editor = this.createEditor();
  this.inputHandler.setTranslator(this.contractedTranslator,
                                  this.uncontractedTranslator);
  editor.setActive(true);
  editor.focus('text');
  this.assertExpandingSelection();

  // First, type a 'b'.
  assertTrue(this.sendCells('12'));
  // Remember that the contracted translator produces uppercase.
  editor.assertContentIs('BUT', 'BUT'.length);
  this.assertExpandingNone();

  // From here on, the input handler needs to replace already entered text.
  editor.setAllowDeletes(true);
  // Typing 'rl' changes to a different contraction.
  assertTrue(this.sendCells('1235 123'));
  editor.assertContentIs('BRAILLE', 'BRAILLE'.length);
  // Now, finish the word.
  assertTrue(this.sendCells('0'));
  editor.assertContentIs('BRAILLE ', 'BRAILLE '.length);
  this.assertExpandingNone();

  // Move the cursor to the beginning.
  editor.select(0);
  this.assertExpandingSelection();

  // Typing now uses the uncontracted table.
  assertTrue(this.sendCells('12'));  // 'b'
  editor.assertContentIs('bBRAILLE ', 1);
  this.assertExpandingSelection();
  editor.select('bBRAILLE'.length);
  this.assertExpandingSelection();
  assertTrue(this.sendCells('12')); // 'b'
  editor.assertContentIs('bBRAILLEb ', 'bBRAILLEb'.length);
  // Move to the end, where contracted typing should work.
  editor.select('bBRAILLEb '.length);
  assertTrue(this.sendCells('1456 0'));  // Symbol for 'this', then space.
  this.assertExpandingNone();
  editor.assertContentIs('bBRAILLEb THIS ', 'bBRAILLEb this '.length);

  // Move between the two words.
  editor.select('bBRAILLEb'.length);
  this.assertExpandingSelection();
  assertTrue(this.sendCells('0'));
  assertTrue(this.sendCells('12'));  // 'b' for 'but'
  editor.assertContentIs('bBRAILLEb BUT THIS ', 'bBRAILLEb BUT'.length);
  this.assertExpandingNone();
});


TEST_F('CvoxBrailleInputHandlerUnitTest', 'TypingUrlWithContracted',
       function() {
  var editor = this.createEditor();
  this.inputHandler.setTranslator(this.contractedTranslator,
                                  this.uncontractedTranslator);
  editor.setActive(true);
  editor.focus('url');
  this.assertExpandingAll();
  assertTrue(this.sendCells('1245'));  // 'g'
  editor.insert('oogle.com', true /*select*/);
  editor.assertContentIs('google.com', 1, 'google.com'.length);
  this.assertExpandingAll();
  this.sendCells('135');  // 'o'
  editor.insert('ogle.com', true /*select*/);
  editor.assertContentIs('google.com', 2, 'google.com'.length);
  this.assertExpandingAll();
  this.sendCells('0');
  editor.assertContentIs('go ', 'go '.length);
  // In a URL, even when the cursor is in whitespace, all of the value
  // is expanded to uncontracted braille.
  this.assertExpandingAll();
});


TEST_F('CvoxBrailleInputHandlerUnitTest', 'Backspace', function() {
  var editor = this.createEditor();
  this.inputHandler.setTranslator(this.contractedTranslator,
                                  this.uncontractedTranslator);
  editor.setActive(true);
  editor.focus('text');

  // Add some text that we can delete later.
  editor.setContent('Text ', 'Text '.length);

  // The IME needs to delete text, even when typing.
  editor.setAllowDeletes(true);
  // Type 'brl' to make sure replacement works when deleting text.
  assertTrue(this.sendCells('12 1235 123'));
  editor.assertContentIs('Text BRAILLE', 'Text BRAILLE'.length);

  // Delete what we just typed, one cell at a time.
  this.sendKeyEvent('Backspace');
  editor.assertContentIs('Text BR', 'Text BR'.length);
  this.sendKeyEvent('Backspace');
  editor.assertContentIs('Text BUT', 'Text BUT'.length);
  this.sendKeyEvent('Backspace');
  editor.assertContentIs('Text ', 'Text '.length);

  // Now, backspace should be handled as usual, synthetizing key events.
  assertEquals(0, this.keyEvents.length);
  this.sendKeyEvent('Backspace');
  assertEqualsJSON([{keyCode: 8, keyName: 'Backspace', charValue: 8}],
                   this.keyEvents);
});


TEST_F('CvoxBrailleInputHandlerUnitTest', 'KeysImeNotActive', function() {
  var editor = this.createEditor();
  this.sendKeyEvent('Enter');
  this.sendKeyEvent('ArrowUp');
  assertEqualsJSON([{keyCode: 13, keyName: 'Enter', charValue: 0x0A},
                    {keyCode: 38, keyName: 'ArrowUp', charValue: 0x41}],
                   this.keyEvents);
});