path: root/testing/web-platform/tests/touch-events/multi-touch-interactions.js

setup({explicit_done: true});

var debug = document.getElementById("debug");

function debug_print (x) {
/* uncomment below statement to show debug messages */
// document.getElementById("debug").innerHTML += x;
}

var starting_elements = {};

function check_list_subset_of_targetlist(list, list_name, targetlist, targetlist_name) {
    var exist_in_targetlist;
    for(i=0; i<list.length; i++) {
        exist_in_targetlist=false;
        for(j=0; j<targetlist.length; j++)
            if(list.item(i).identifier==targetlist.item(j).identifier)
                exist_in_targetlist=true;

        assert_true(exist_in_targetlist, list_name + ".item("+i+") exists in " + targetlist_name);
    }
}

function check_list_subset_of_two_targetlists(list, list_name, targetlist1, targetlist1_name, targetlist2, targetlist2_name) {
    var exist_in_targetlists;
    for(i=0; i<list.length; i++) {
        exist_in_targetlists=false;
        for(j=0; j<targetlist1.length; j++)
            if(list.item(i).identifier==targetlist1.item(j).identifier)
                exist_in_targetlists=true;

        if(!exist_in_targetlists)
            for(j=0; j<targetlist2.length; j++)
                if(list.item(i).identifier==targetlist2.item(j).identifier)
                    exist_in_targetlists=true;

        assert_true(exist_in_targetlists, list_name + ".item("+i+") exists in " + targetlist1_name + " or " + targetlist2_name);
    }

}

function is_at_least_one_item_in_targetlist(list, targetlist) {
    for(i=0; i<list.length; i++)
        for(j=0; j<targetlist.length; j++)
            if(list.item(i).identifier==targetlist.item(j).identifier)
                return true;

    return false;
}

function check_no_item_in_targetlist(list, list_name, targetlist, targetlist_name) {
    for(i=0; i<list.length; i++)
        for(j=0; j<targetlist.length; j++) {
            assert_false(list.item(i).identifier==targetlist.item(j).identifier, list_name + ".item("+i+") exists in " + targetlist_name);
            return;
        }
}

function check_targets(list, target) {
    for(i=0; i<list.length; i++)
        assert_true(list.item(i).target==target, "item(" + i + ").target is element receiving event");
}

function check_starting_elements(list) {
    for (i=0; i<list.length; i++) {
        assert_equals(list.item(i).target, starting_elements[list.item(i).identifier], "item(" + i + ").target matches starting element");
    }
}

function run() {
    var target0 = document.getElementById("target0");
    var target1 = document.getElementById("target1");

    var test_touchstart = async_test("touchstart event received");
    var test_touchmove = async_test("touchmove event received");
    var test_touchend = async_test("touchend event received");
    var test_mousedown = async_test("Interaction with mouse events");

    var touchstart_received = 0;
    var touchmove_received = 0;
    var touchend_received = 0;
    var touchstart_identifier;

    // last received touch lists for comparison
    var last_touches;
    var last_targetTouches={};
    var last_changedTouches={};

    var actions_promise;

    on_event(window, "touchstart", function onTouchStart(ev) {
        // process event only if it's targeted at target0 or target1
        if(ev.target != target0 && ev.target != target1 )
            return;

        ev.preventDefault();

        if(!touchstart_received) {
            // Check event ordering TA: 1.6.1
            test_touchstart.step(function() {
                assert_equals(touchmove_received, 0, "touchstart precedes touchmove");
                assert_equals(touchend_received, 0, "touchstart precedes touchend");
            });
            test_touchstart.done();
            test_mousedown.done(); // If we got here, then the mouse event test is not needed.
        }
        touchstart_received++;

        // TA: 1.3.2.2, 1.3.2.4
        test(function() {
            assert_true(ev.changedTouches.length >= 1, "changedTouches.length is at least 1");
            assert_true(ev.changedTouches.length <= ev.touches.length, "changedTouches.length is smaller than touches.length");
            check_list_subset_of_targetlist(ev.changedTouches, "changedTouches", ev.touches, "touches");
        }, "touchstart #" + touchstart_received + ": changedTouches is a subset of touches");

        // TA: 1.3.3.2, 1.3.3.3
        test(function() {
            assert_true(ev.targetTouches.length >= 1, "targetTouches.length is at least 1");
            assert_true(ev.targetTouches.length <= ev.touches.length, "targetTouches.length is smaller than touches.length");
            check_list_subset_of_targetlist(ev.targetTouches, "targetTouches", ev.touches, "touches");
        }, "touchstart #" + touchstart_received + ": targetTouches is a subset of touches");

        // TA: 1.3.3.9
        test(function() {
            check_targets(ev.targetTouches, ev.target);
        }, "touchstart #" + touchstart_received + ": targets of targetTouches are correct");

        // TA: 1.3.4.2
        test(function() {
            assert_true(ev.touches.length >= 1, "touches.length is at least 1");
        }, "touchstart #" + touchstart_received + ": touches.length is valid");

        if(touchstart_received == 1) {
            // TA: 1.3.3.5, 1.3.3.7
            test(function() {
                assert_true(ev.targetTouches.length <= ev.changedTouches.length, "targetTouches.length is smaller than changedTouches.length");
                check_list_subset_of_targetlist(ev.targetTouches, "targetTouches", ev.changedTouches, "changedTouches");
            }, "touchstart #" + touchstart_received + ": targetTouches is a subset of changedTouches");

            // TA: 1.3.4.3
            test(function() {
                assert_equals(ev.touches.length, ev.changedTouches.length, "touches and changedTouches have the same length");
            }, "touchstart #" + touchstart_received + ": touches and changedTouches have the same length");
        } else {
            // TA: 1.3.3.6
            test(function() {
                var diff_in_targetTouches = ev.targetTouches.length - (last_targetTouches[ev.target.id] ? last_targetTouches[ev.target.id].length : 0);
                assert_true(diff_in_targetTouches > 0, "targetTouches.length is larger than last received targetTouches.length");
                assert_true(diff_in_targetTouches <= ev.changedTouches.length, "change in targetTouches.length is smaller than changedTouches.length");
            }, "touchstart #" + touchstart_received + ": change in targetTouches.length is valid");

            // TA: 1.3.3.8
            test(function() {
                assert_true(is_at_least_one_item_in_targetlist(ev.targetTouches, ev.changedTouches), "at least one item of targetTouches is in changedTouches");
            }, "touchstart #" + touchstart_received + ": at least one targetTouches item in changedTouches");

            // TA: 1.3.4.4
            test(function() {
                var diff_in_touches = ev.touches.length - last_touches.length;
                assert_true(diff_in_touches > 0, "touches.length is larger than last received touches.length");
                assert_equals(diff_in_touches, ev.changedTouches.length, "change in touches.length equals changedTouches.length");
            }, "touchstart #" + touchstart_received + ": change in touches.length is valid");

            // TA: 1.3.4.5
            test(function() {
                check_list_subset_of_two_targetlists(ev.touches, "touches", ev.changedTouches, "changedTouches", last_touches, "last touches");
            }, "touchstart #" + touchstart_received + ": touches is subset of {changedTouches, last received touches}");
        }

        // save starting element of each new touch point
        for (i=0; i<ev.changedTouches.length; i++) {
            starting_elements[ev.changedTouches.item(i).identifier] = ev.changedTouches.item(i).target;
        }

        last_touches = ev.touches;
        last_targetTouches[ev.target.id] = ev.targetTouches;
        last_changedTouches = {};    // changedTouches are only saved for touchend events
    });

    on_event(window, "touchmove", function onTouchMove(ev) {
        // process event only if it's targeted at target0 or target1
        if(ev.target != target0 && ev.target != target1 )
            return;

        ev.preventDefault();

        // TA: 1.6.1
        test_touchmove.step(function() {
            assert_true(touchstart_received>0, "touchmove follows touchstart");
            // assert_false(touchend_received, "touchmove precedes touchend"); // this applies to scenario tests
        });
        test_touchmove.done();

        touchmove_received++;

        // do the detailed checking only for a few times
        if(touchmove_received<6) {
            // TA: 1.4.2.2, 1.4.2.4
            test(function() {
                assert_true(ev.changedTouches.length >= 1, "changedTouches.length is at least 1");
                assert_true(ev.changedTouches.length <= ev.touches.length, "changedTouches.length is smaller than touches.length");
                check_list_subset_of_targetlist(ev.changedTouches, "changedTouches", ev.touches, "touches");
            }, "touchmove #" + touchmove_received + ": changedTouches is a subset of touches");

            // TA: 1.4.3.2, 1.4.3.4
            test(function() {
                assert_true(ev.targetTouches.length >= 1, "targetTouches.length is at least 1");
                assert_true(ev.targetTouches.length <= ev.touches.length, "targetTouches.length is smaller than touches.length");
                check_list_subset_of_targetlist(ev.targetTouches, "targetTouches", ev.touches, "touches");
            }, "touchmove #" + touchmove_received + ": targetTouches is a subset of touches");

            // TA: 1.4.3.6
            test(function() {
                assert_true(is_at_least_one_item_in_targetlist(ev.targetTouches, ev.changedTouches), "at least one item of targetTouches is in changedTouches");
            }, "touchmove #" + touchmove_received + ": at least one targetTouches item in changedTouches");

            // TA: 1.4.3.8
            test(function() {
                check_targets(ev.targetTouches, ev.target);
            }, "touchmove #" + touchmove_received + ": targets of targetTouches are correct");

            // TA: 1.4.4.2
            test(function() {
                assert_equals(ev.touches.length, last_touches.length, "length of touches is same as length of last received touches");
                check_list_subset_of_targetlist(ev.touches, "touches", last_touches, "last received touches");
            }, "touchmove #" + touchmove_received + ": touches must be same as last received touches");

            // TA: 1.6.3
            check_starting_elements(ev.changedTouches);
        }

        last_touches = ev.touches;
        last_targetTouches[ev.target.id] = ev.targetTouches;
        last_changedTouches = {};    // changedTouches are only saved for touchend events
    });

    on_event(window, "touchend", function onTouchEnd(ev) {
        // process event only if it's targeted at target0 or target1
        if(ev.target != target0 && ev.target != target1 )
            return;

        test_touchend.step(function() {
            assert_true(touchstart_received>0, "touchend follows touchstart");
        });
        test_touchend.done();

        touchend_received++;

        debug_print("touchend #" + touchend_received + ":<br>");
        debug_print("changedTouches.length=" + ev.changedTouches.length + "<br>");
        debug_print("targetTouches.length=" + ev.targetTouches.length + "<br>");
        debug_print("touches.length=" + ev.touches.length + "<br>");
        for(i=0; i<ev.changedTouches.length; i++)
            debug_print("changedTouches.item(" + i + ").target=" + ev.changedTouches.item(i).target.id + "<br>");

        // TA: 1.5.2.2
        test(function() {
            assert_true(ev.changedTouches.length >= 1, "changedTouches.length is at least 1");
        }, "touchend #" + touchend_received + ": length of changedTouches is valid");

        // TA: 1.5.2.3
        test(function() {
            check_list_subset_of_targetlist(ev.changedTouches, "changedTouches", last_touches, "last received touches");
        }, "touchend #" + touchend_received + ": changedTouches is a subset of last received touches");

        // TA: 1.5.2.4, 1.5.2.5
        test(function() {
            check_no_item_in_targetlist(ev.changedTouches, "changedTouches", ev.touches, "touches");
            check_no_item_in_targetlist(ev.changedTouches, "changedTouches", ev.targetTouches, "targetTouches");
        }, "touchend #" + touchend_received + ": no item in changedTouches are in touches or targetTouches");

        // TA: 1.5.2.6
        test(function() {
            var found=false;
            for (i=0; i<ev.changedTouches.length; i++)
                if (ev.changedTouches.item(i).target == ev.target)
                    found=true;
            assert_true(found, "at least one item in changedTouches has matching target");
        }, "touchend #" + touchend_received + ": at least one item in changedTouches targeted at this element");

        // TA: 1.5.3.2, 1.5.3.3
        test(function() {
            assert_true(ev.targetTouches.length >= 0, "targetTouches.length is non-negative");
            assert_true(ev.targetTouches.length <= ev.touches.length, "targetTouches.length is smaller than touches.length");
            check_list_subset_of_targetlist(ev.targetTouches, "targetTouches", ev.touches, "touches");
        }, "touchend #" + touchend_received + ": targetTouches is a subset of touches");

        // TA: 1.5.3.5 (new)
        test(function() {
            check_targets(ev.targetTouches, ev.target);
        }, "touchend #" + touchend_received + ": targets of targetTouches are correct");

        // In some cases, when multiple touch points are released simultaneously
        // the UA would dispatch the "same" touchend event (same changedTouches, same touches, but possibly different targetTouches)
        // to each of the elements that are starting elements of the released touch points.
        // in these situations, the subsequent events are exempt from TA 1.5.3.4 and 1.5.4.2
        var same_event_as_last = false;
        if (last_changedTouches && last_changedTouches.length==ev.changedTouches.length) {
            same_event_as_last = true; // assume true until proven otherwise
            for (i=0; i<last_changedTouches.length; i++) {
                var match = false;
                for (j=0; j<ev.changedTouches.length; j++)
                    if (last_changedTouches.item(i) == ev.changedTouches.item(j)) {
                        match = true;
                        break;
                    }
                if (!match)
                    same_event_as_last = false;
            }
        }

        if (!same_event_as_last) {
            // TA: 1.5.3.4
            // Getting semi-random failures on this and 1.5.4.2.
            // See 1.5.4.2. Not sure if it's the same issue...
            test(function() {
                assert_true(last_targetTouches[ev.target.id].length > 0, "last received targetTouches.length is not zero");
                var diff_in_targetTouches = last_targetTouches[ev.target.id].length - ev.targetTouches.length;
                debug_print("diff_in_targetTouches=" + diff_in_targetTouches + "<br>");
                assert_true(diff_in_targetTouches > 0, "targetTouches.length is smaller than last received targetTouches.length");
                assert_true(diff_in_targetTouches <= ev.changedTouches.length, "change in targetTouches.length is smaller than changedTouches.length");
            }, "touchend #" + touchend_received + ": change in targetTouches.length is valid");

            // TA: 1.5.4.2
            // Getting semi-random failures on this and 1.5.3.4.
            // It looks like if fingers are lifted simultaneously, the "same" touchend event can be dispatched to two target elements
            // but adapted to the element (same touches, changedTouches but different targetTouches).
            // When one event is processed after another, ev.touches would end up being identical to last_touches, leading  to failure.
            // Question is why done() does not stop the processing of the latter event.
            test(function() {
                assert_true(last_touches.length > 0, "last received touches.length is not zero");
                var diff_in_touches = last_touches.length - ev.touches.length;
                debug_print("diff_in_touches=" + diff_in_touches + "<br>");
                assert_true(diff_in_touches > 0, "touches.length is smaller than last received touches.length");
                assert_equals(diff_in_touches, ev.changedTouches.length, "change in touches.length equals changedTouches.length");
            }, "touchend #" + touchend_received + ": change in touches.length is valid");
        }

        // TA: 1.6.4
        debug_print("touchend #" + touchend_received + ": TA 1.6.4<br>");
        test(function() {
            check_starting_elements(ev.changedTouches);
        }, "touchend #" + touchend_received + ": event dispatched to correct element<br>");

        debug_print("touchend #" + touchend_received + ": saving touch lists<br>");

        last_touches = ev.touches;
        last_targetTouches[ev.target.id] = ev.targetTouches;
        last_changedTouches = ev.changedTouches;

        debug_print("touchend #" + touchend_received + ": done<br>");
        if(ev.touches.length==0)
            actions_promise.then( () => done() );
    });

    on_event(target0, "mousedown", function onMouseDown(ev) {
        test_mousedown.step(function() {
            assert_true(touchstart_received,
                "The touchstart event must be dispatched before any mouse " +
                "events. (If this fails, it might mean that the user agent does " +
                "not implement W3C touch events at all.)"
            );
        });
        test_mousedown.done();

        if (!touchstart_received) {
            // Abort the tests.  If touch events are not supported, then most of
            // the other event handlers will never be called, and the test will
            // time out with misleading results.
            done();
        }
    });

    actions_promise = new test_driver.Actions()
          .addPointer("touchPointer1", "touch")
          .addPointer("touchPointer2", "touch")
          .addPointer("touchPointer3", "touch")
          .pointerMove(0, 0, {origin: target0, sourceName: "touchPointer1"})
          .pointerMove(3, 0, {origin: target0, sourceName: "touchPointer2"})
          .pointerDown({sourceName: "touchPointer1"})
          .pointerDown({sourceName: "touchPointer2"})
          .pointerMove(0, 10, {origin: target0, sourceName: "touchPointer1"})
          .pointerMove(3, 10, {origin: target0, sourceName: "touchPointer2"})
          .pointerMove(0, 0, {origin: target1, sourceName: "touchPointer1"})
          .pointerMove(3, 0, {origin: target1, sourceName: "touchPointer2"})
          .pointerMove(6, 0, {origin: target0, sourceName: "touchPointer3"})
          .pointerDown({sourceName: "touchPointer3"})
          .pointerUp({sourceName: "touchPointer1"})
          .pointerUp({sourceName: "touchPointer2"})
          .pointerUp({sourceName: "touchPointer3"})
          .send();
}