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path: root/accessible/tests/mochitest/pivot.js
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/* import-globals-from common.js */
/* import-globals-from events.js */
/* import-globals-from role.js */
/* import-globals-from states.js */
/* import-globals-from text.js */

ChromeUtils.import("resource://gre/modules/XPCOMUtils.jsm");

// //////////////////////////////////////////////////////////////////////////////
// Constants

const PREFILTER_INVISIBLE = nsIAccessibleTraversalRule.PREFILTER_INVISIBLE;
const PREFILTER_TRANSPARENT = nsIAccessibleTraversalRule.PREFILTER_TRANSPARENT;
const FILTER_MATCH = nsIAccessibleTraversalRule.FILTER_MATCH;
const FILTER_IGNORE = nsIAccessibleTraversalRule.FILTER_IGNORE;
const FILTER_IGNORE_SUBTREE = nsIAccessibleTraversalRule.FILTER_IGNORE_SUBTREE;
const NO_BOUNDARY = nsIAccessiblePivot.NO_BOUNDARY;
const CHAR_BOUNDARY = nsIAccessiblePivot.CHAR_BOUNDARY;
const WORD_BOUNDARY = nsIAccessiblePivot.WORD_BOUNDARY;

const NS_ERROR_NOT_IN_TREE = 0x80780026;
const NS_ERROR_INVALID_ARG = 0x80070057;

// //////////////////////////////////////////////////////////////////////////////
// Traversal rules

/**
 * Rule object to traverse all focusable nodes and text nodes.
 */
var HeadersTraversalRule = {
  getMatchRoles() {
    return [ROLE_HEADING];
  },

  preFilter: PREFILTER_INVISIBLE,

  match(aAccessible) {
    return FILTER_MATCH;
  },

  QueryInterface: ChromeUtils.generateQI([nsIAccessibleTraversalRule]),
};

/**
 * Traversal rule for all focusable nodes or leafs.
 */
var ObjectTraversalRule = {
  getMatchRoles() {
    return [];
  },

  preFilter: PREFILTER_INVISIBLE | PREFILTER_TRANSPARENT,

  match(aAccessible) {
    var rv = FILTER_IGNORE;
    var role = aAccessible.role;
    if (
      hasState(aAccessible, STATE_FOCUSABLE) &&
      role != ROLE_DOCUMENT &&
      role != ROLE_INTERNAL_FRAME
    ) {
      rv = FILTER_IGNORE_SUBTREE | FILTER_MATCH;
    } else if (
      aAccessible.childCount == 0 &&
      role != ROLE_LISTITEM_MARKER &&
      aAccessible.name.trim()
    ) {
      rv = FILTER_MATCH;
    }

    return rv;
  },

  QueryInterface: ChromeUtils.generateQI([nsIAccessibleTraversalRule]),
};

// //////////////////////////////////////////////////////////////////////////////
// Virtual state invokers and checkers

/**
 * A checker for virtual cursor changed events.
 */
function VCChangedChecker(
  aDocAcc,
  aIdOrNameOrAcc,
  aTextOffsets,
  aPivotMoveMethod,
  aIsFromUserInput,
  aBoundaryType = NO_BOUNDARY
) {
  this.__proto__ = new invokerChecker(EVENT_VIRTUALCURSOR_CHANGED, aDocAcc);

  this.match = function VCChangedChecker_match(aEvent) {
    var event = null;
    try {
      event = aEvent.QueryInterface(nsIAccessibleVirtualCursorChangeEvent);
    } catch (e) {
      return false;
    }

    var expectedReason =
      VCChangedChecker.methodReasonMap[aPivotMoveMethod] ||
      nsIAccessiblePivot.REASON_NONE;

    return (
      event.reason == expectedReason && event.boundaryType == aBoundaryType
    );
  };

  this.check = function VCChangedChecker_check(aEvent) {
    SimpleTest.info("VCChangedChecker_check");

    var event = null;
    try {
      event = aEvent.QueryInterface(nsIAccessibleVirtualCursorChangeEvent);
    } catch (e) {
      SimpleTest.ok(false, "Does not support correct interface: " + e);
    }

    var position = aDocAcc.virtualCursor.position;
    var idMatches = position && position.DOMNode.id == aIdOrNameOrAcc;
    var nameMatches = position && position.name == aIdOrNameOrAcc;
    var accMatches = position == aIdOrNameOrAcc;

    SimpleTest.ok(
      idMatches || nameMatches || accMatches,
      "id or name matches - expecting " +
        prettyName(aIdOrNameOrAcc) +
        ", got '" +
        prettyName(position)
    );

    SimpleTest.is(
      aEvent.isFromUserInput,
      aIsFromUserInput,
      "Expected user input is " + aIsFromUserInput + "\n"
    );

    SimpleTest.is(
      event.newAccessible,
      position,
      "new position in event is incorrect"
    );

    if (aTextOffsets) {
      SimpleTest.is(
        aDocAcc.virtualCursor.startOffset,
        aTextOffsets[0],
        "wrong start offset"
      );
      SimpleTest.is(
        aDocAcc.virtualCursor.endOffset,
        aTextOffsets[1],
        "wrong end offset"
      );
      SimpleTest.is(
        event.newStartOffset,
        aTextOffsets[0],
        "wrong start offset in event"
      );
      SimpleTest.is(
        event.newEndOffset,
        aTextOffsets[1],
        "wrong end offset in event"
      );
    }

    var prevPosAndOffset = VCChangedChecker.getPreviousPosAndOffset(
      aDocAcc.virtualCursor
    );

    if (prevPosAndOffset) {
      SimpleTest.is(
        event.oldAccessible,
        prevPosAndOffset.position,
        "previous position does not match"
      );
      SimpleTest.is(
        event.oldStartOffset,
        prevPosAndOffset.startOffset,
        "previous start offset does not match"
      );
      SimpleTest.is(
        event.oldEndOffset,
        prevPosAndOffset.endOffset,
        "previous end offset does not match"
      );
    }
  };
}

VCChangedChecker.prevPosAndOffset = {};

VCChangedChecker.storePreviousPosAndOffset = function storePreviousPosAndOffset(
  aPivot
) {
  VCChangedChecker.prevPosAndOffset[aPivot] = {
    position: aPivot.position,
    startOffset: aPivot.startOffset,
    endOffset: aPivot.endOffset,
  };
};

VCChangedChecker.getPreviousPosAndOffset = function getPreviousPosAndOffset(
  aPivot
) {
  return VCChangedChecker.prevPosAndOffset[aPivot];
};

VCChangedChecker.methodReasonMap = {
  moveNext: nsIAccessiblePivot.REASON_NEXT,
  movePrevious: nsIAccessiblePivot.REASON_PREV,
  moveFirst: nsIAccessiblePivot.REASON_FIRST,
  moveLast: nsIAccessiblePivot.REASON_LAST,
  setTextRange: nsIAccessiblePivot.REASON_NONE,
  moveNextByText: nsIAccessiblePivot.REASON_NEXT,
  movePreviousByText: nsIAccessiblePivot.REASON_PREV,
  moveToPoint: nsIAccessiblePivot.REASON_POINT,
};

/**
 * Set a text range in the pivot and wait for virtual cursor change event.
 *
 * @param aDocAcc         [in] document that manages the virtual cursor
 * @param aTextAccessible [in] accessible to set to virtual cursor's position
 * @param aTextOffsets    [in] start and end offsets of text range to set in
 *                        virtual cursor.
 */
function setVCRangeInvoker(aDocAcc, aTextAccessible, aTextOffsets) {
  this.invoke = function virtualCursorChangedInvoker_invoke() {
    VCChangedChecker.storePreviousPosAndOffset(aDocAcc.virtualCursor);
    SimpleTest.info(prettyName(aTextAccessible) + " " + aTextOffsets);
    aDocAcc.virtualCursor.setTextRange(
      aTextAccessible,
      aTextOffsets[0],
      aTextOffsets[1]
    );
  };

  this.getID = function setVCRangeInvoker_getID() {
    return (
      "Set offset in " +
      prettyName(aTextAccessible) +
      " to (" +
      aTextOffsets[0] +
      ", " +
      aTextOffsets[1] +
      ")"
    );
  };

  this.eventSeq = [
    new VCChangedChecker(
      aDocAcc,
      aTextAccessible,
      aTextOffsets,
      "setTextRange",
      true
    ),
  ];
}

/**
 * Move the pivot and wait for virtual cursor change event.
 *
 * @param aDocAcc          [in] document that manages the virtual cursor
 * @param aPivotMoveMethod [in] method to test (ie. "moveNext", "moveFirst", etc.)
 * @param aRule            [in] traversal rule object
 * @param aIdOrNameOrAcc   [in] id, accessible or accessible name to expect
 *                         virtual cursor to land on after performing move method.
 *                         false if no move is expected.
 * @param aIsFromUserInput [in] set user input flag when invoking method, and
 *                         expect it in the event.
 */
function setVCPosInvoker(
  aDocAcc,
  aPivotMoveMethod,
  aRule,
  aIdOrNameOrAcc,
  aIsFromUserInput
) {
  // eslint-disable-next-line mozilla/no-compare-against-boolean-literals
  var expectMove = aIdOrNameOrAcc != false;
  this.invoke = function virtualCursorChangedInvoker_invoke() {
    VCChangedChecker.storePreviousPosAndOffset(aDocAcc.virtualCursor);
    if (aPivotMoveMethod && aRule) {
      var moved = false;
      switch (aPivotMoveMethod) {
        case "moveFirst":
        case "moveLast":
          moved = aDocAcc.virtualCursor[aPivotMoveMethod](
            aRule,
            aIsFromUserInput === undefined ? true : aIsFromUserInput
          );
          break;
        case "moveNext":
        case "movePrevious":
          moved = aDocAcc.virtualCursor[aPivotMoveMethod](
            aRule,
            aDocAcc.virtualCursor.position,
            false,
            aIsFromUserInput === undefined ? true : aIsFromUserInput
          );
          break;
      }
      SimpleTest.is(
        !!moved,
        !!expectMove,
        "moved pivot with " + aPivotMoveMethod + " to " + aIdOrNameOrAcc
      );
    } else {
      aDocAcc.virtualCursor.position = getAccessible(aIdOrNameOrAcc);
    }
  };

  this.getID = function setVCPosInvoker_getID() {
    return "Do " + (expectMove ? "" : "no-op ") + aPivotMoveMethod;
  };

  if (expectMove) {
    this.eventSeq = [
      new VCChangedChecker(
        aDocAcc,
        aIdOrNameOrAcc,
        null,
        aPivotMoveMethod,
        aIsFromUserInput === undefined ? !!aPivotMoveMethod : aIsFromUserInput
      ),
    ];
  } else {
    this.eventSeq = [];
    this.unexpectedEventSeq = [
      new invokerChecker(EVENT_VIRTUALCURSOR_CHANGED, aDocAcc),
    ];
  }
}

/**
 * Move the pivot by text and wait for virtual cursor change event.
 *
 * @param aDocAcc          [in] document that manages the virtual cursor
 * @param aPivotMoveMethod [in] method to test (ie. "moveNext", "moveFirst", etc.)
 * @param aBoundary        [in] boundary constant
 * @param aTextOffsets     [in] start and end offsets of text range to set in
 *                         virtual cursor.
 * @param aIdOrNameOrAcc   [in] id, accessible or accessible name to expect
 *                         virtual cursor to land on after performing move method.
 *                         false if no move is expected.
 * @param aIsFromUserInput [in] set user input flag when invoking method, and
 *                         expect it in the event.
 */
function setVCTextInvoker(
  aDocAcc,
  aPivotMoveMethod,
  aBoundary,
  aTextOffsets,
  aIdOrNameOrAcc,
  aIsFromUserInput
) {
  // eslint-disable-next-line mozilla/no-compare-against-boolean-literals
  var expectMove = aIdOrNameOrAcc != false;
  this.invoke = function virtualCursorChangedInvoker_invoke() {
    VCChangedChecker.storePreviousPosAndOffset(aDocAcc.virtualCursor);
    SimpleTest.info(aDocAcc.virtualCursor.position);
    var moved = aDocAcc.virtualCursor[aPivotMoveMethod](
      aBoundary,
      aIsFromUserInput === undefined
    );
    SimpleTest.is(
      !!moved,
      !!expectMove,
      "moved pivot by text with " + aPivotMoveMethod + " to " + aIdOrNameOrAcc
    );
  };

  this.getID = function setVCPosInvoker_getID() {
    return (
      "Do " +
      (expectMove ? "" : "no-op ") +
      aPivotMoveMethod +
      " in " +
      prettyName(aIdOrNameOrAcc) +
      ", " +
      boundaryToString(aBoundary) +
      ", [" +
      aTextOffsets +
      "]"
    );
  };

  if (expectMove) {
    this.eventSeq = [
      new VCChangedChecker(
        aDocAcc,
        aIdOrNameOrAcc,
        aTextOffsets,
        aPivotMoveMethod,
        aIsFromUserInput === undefined ? true : aIsFromUserInput,
        aBoundary
      ),
    ];
  } else {
    this.eventSeq = [];
    this.unexpectedEventSeq = [
      new invokerChecker(EVENT_VIRTUALCURSOR_CHANGED, aDocAcc),
    ];
  }
}

/**
 * Move the pivot to the position under the point.
 *
 * @param aDocAcc        [in] document that manages the virtual cursor
 * @param aX             [in] screen x coordinate
 * @param aY             [in] screen y coordinate
 * @param aIgnoreNoMatch [in] don't unset position if no object was found at
 *                       point.
 * @param aRule          [in] traversal rule object
 * @param aIdOrNameOrAcc [in] id, accessible or accessible name to expect
 *                       virtual cursor to land on after performing move method.
 *                       false if no move is expected.
 */
function moveVCCoordInvoker(
  aDocAcc,
  aX,
  aY,
  aIgnoreNoMatch,
  aRule,
  aIdOrNameOrAcc
) {
  // eslint-disable-next-line mozilla/no-compare-against-boolean-literals
  var expectMove = aIdOrNameOrAcc != false;
  this.invoke = function virtualCursorChangedInvoker_invoke() {
    VCChangedChecker.storePreviousPosAndOffset(aDocAcc.virtualCursor);
    var moved = aDocAcc.virtualCursor.moveToPoint(
      aRule,
      aX,
      aY,
      aIgnoreNoMatch
    );
    SimpleTest.ok(
      (expectMove && moved) || (!expectMove && !moved),
      "moved pivot"
    );
  };

  this.getID = function setVCPosInvoker_getID() {
    return (
      "Do " + (expectMove ? "" : "no-op ") + "moveToPoint " + aIdOrNameOrAcc
    );
  };

  if (expectMove) {
    this.eventSeq = [
      new VCChangedChecker(aDocAcc, aIdOrNameOrAcc, null, "moveToPoint", true),
    ];
  } else {
    this.eventSeq = [];
    this.unexpectedEventSeq = [
      new invokerChecker(EVENT_VIRTUALCURSOR_CHANGED, aDocAcc),
    ];
  }
}

/**
 * Change the pivot modalRoot
 *
 * @param aDocAcc         [in] document that manages the virtual cursor
 * @param aModalRootAcc   [in] accessible of the modal root, or null
 * @param aExpectedResult [in] error result expected. 0 if expecting success
 */
function setModalRootInvoker(aDocAcc, aModalRootAcc, aExpectedResult) {
  this.invoke = function setModalRootInvoker_invoke() {
    var errorResult = 0;
    try {
      aDocAcc.virtualCursor.modalRoot = aModalRootAcc;
    } catch (x) {
      SimpleTest.ok(
        x.result,
        "Unexpected exception when changing modal root: " + x
      );
      errorResult = x.result;
    }

    SimpleTest.is(
      errorResult,
      aExpectedResult,
      "Did not get expected result when changing modalRoot"
    );
  };

  this.getID = function setModalRootInvoker_getID() {
    return "Set modalRoot to " + prettyName(aModalRootAcc);
  };

  this.eventSeq = [];
  this.unexpectedEventSeq = [
    new invokerChecker(EVENT_VIRTUALCURSOR_CHANGED, aDocAcc),
  ];
}

/**
 * Add invokers to a queue to test a rule and an expected sequence of element ids
 * or accessible names for that rule in the given document.
 *
 * @param aQueue     [in] event queue in which to push invoker sequence.
 * @param aDocAcc    [in] the managing document of the virtual cursor we are
 *                   testing
 * @param aRule      [in] the traversal rule to use in the invokers
 * @param aModalRoot [in] a modal root to use in this traversal sequence
 * @param aSequence  [in] a sequence of accessible names or element ids to expect
 *                   with the given rule in the given document
 */
function queueTraversalSequence(aQueue, aDocAcc, aRule, aModalRoot, aSequence) {
  aDocAcc.virtualCursor.position = null;

  // Add modal root (if any)
  aQueue.push(new setModalRootInvoker(aDocAcc, aModalRoot, 0));

  aQueue.push(new setVCPosInvoker(aDocAcc, "moveFirst", aRule, aSequence[0]));

  for (let i = 1; i < aSequence.length; i++) {
    let invoker = new setVCPosInvoker(aDocAcc, "moveNext", aRule, aSequence[i]);
    aQueue.push(invoker);
  }

  // No further more matches for given rule, expect no virtual cursor changes.
  aQueue.push(new setVCPosInvoker(aDocAcc, "moveNext", aRule, false));

  for (let i = aSequence.length - 2; i >= 0; i--) {
    let invoker = new setVCPosInvoker(
      aDocAcc,
      "movePrevious",
      aRule,
      aSequence[i]
    );
    aQueue.push(invoker);
  }

  // No previous more matches for given rule, expect no virtual cursor changes.
  aQueue.push(new setVCPosInvoker(aDocAcc, "movePrevious", aRule, false));

  aQueue.push(
    new setVCPosInvoker(
      aDocAcc,
      "moveLast",
      aRule,
      aSequence[aSequence.length - 1]
    )
  );

  // No further more matches for given rule, expect no virtual cursor changes.
  aQueue.push(new setVCPosInvoker(aDocAcc, "moveNext", aRule, false));

  // set isFromUserInput to false, just to test..
  aQueue.push(
    new setVCPosInvoker(aDocAcc, "moveFirst", aRule, aSequence[0], false)
  );

  // No previous more matches for given rule, expect no virtual cursor changes.
  aQueue.push(new setVCPosInvoker(aDocAcc, "movePrevious", aRule, false));

  // Remove modal root (if any).
  aQueue.push(new setModalRootInvoker(aDocAcc, null, 0));
}

/**
 * A checker for removing an accessible while the virtual cursor is on it.
 */
function removeVCPositionChecker(aDocAcc, aHiddenParentAcc) {
  this.__proto__ = new invokerChecker(EVENT_REORDER, aHiddenParentAcc);

  this.check = function removeVCPositionChecker_check(aEvent) {
    var errorResult = 0;
    try {
      aDocAcc.virtualCursor.moveNext(ObjectTraversalRule);
    } catch (x) {
      errorResult = x.result;
    }
    SimpleTest.is(
      errorResult,
      NS_ERROR_NOT_IN_TREE,
      "Expecting NOT_IN_TREE error when moving pivot from invalid position."
    );
  };
}

/**
 * Put the virtual cursor's position on an object, and then remove it.
 *
 * @param aDocAcc     [in] document that manages the virtual cursor
 * @param aPosNode    [in] DOM node to hide after virtual cursor's position is
 *                    set to it.
 */
function removeVCPositionInvoker(aDocAcc, aPosNode) {
  this.accessible = getAccessible(aPosNode);
  this.invoke = function removeVCPositionInvoker_invoke() {
    aDocAcc.virtualCursor.position = this.accessible;
    aPosNode.remove();
  };

  this.getID = function removeVCPositionInvoker_getID() {
    return "Bring virtual cursor to accessible, and remove its DOM node.";
  };

  this.eventSeq = [
    new removeVCPositionChecker(aDocAcc, this.accessible.parent),
  ];
}

/**
 * A checker for removing the pivot root and then calling moveFirst, and
 * checking that an exception is thrown.
 */
function removeVCRootChecker(aPivot) {
  this.__proto__ = new invokerChecker(EVENT_REORDER, aPivot.root.parent);

  this.check = function removeVCRootChecker_check(aEvent) {
    var errorResult = 0;
    try {
      aPivot.moveLast(ObjectTraversalRule);
    } catch (x) {
      errorResult = x.result;
    }
    SimpleTest.is(
      errorResult,
      NS_ERROR_NOT_IN_TREE,
      "Expecting NOT_IN_TREE error when moving pivot from invalid position."
    );
  };
}

/**
 * Create a pivot, remove its root, and perform an operation where the root is
 * needed.
 *
 * @param aRootNode [in] DOM node of which accessible will be the root of the
 *                       pivot. Should have more than one child.
 */
function removeVCRootInvoker(aRootNode) {
  this.pivot = gAccService.createAccessiblePivot(getAccessible(aRootNode));
  this.invoke = function removeVCRootInvoker_invoke() {
    this.pivot.position = this.pivot.root.firstChild;
    aRootNode.remove();
  };

  this.getID = function removeVCRootInvoker_getID() {
    return "Remove root of pivot from tree.";
  };

  this.eventSeq = [new removeVCRootChecker(this.pivot)];
}

/**
 * A debug utility for writing proper sequences for queueTraversalSequence.
 */
function dumpTraversalSequence(aPivot, aRule) {
  var sequence = [];
  if (aPivot.moveFirst(aRule)) {
    do {
      sequence.push("'" + prettyName(aPivot.position) + "'");
    } while (aPivot.moveNext(aRule));
  }
  SimpleTest.info("\n[" + sequence.join(", ") + "]\n");
}