<!doctype html>
<meta charset=utf-8>
<title>RTCPeerConnection.prototype.createDataChannel</title>
<script src=/resources/testharness.js></script>
<script src=/resources/testharnessreport.js></script>
<script src="RTCPeerConnection-helper.js"></script>
<script>
'use strict';

// Test is based on the following revision:
// https://rawgit.com/w3c/webrtc-pc/1cc5bfc3ff18741033d804c4a71f7891242fb5b3/webrtc.html

/*
  6.1.  RTCPeerConnection Interface Extensions

    partial interface RTCPeerConnection {
        [...]
        RTCDataChannel createDataChannel(USVString label,
                                         optional RTCDataChannelInit dataChannelDict);
        [...]
    };

  6.2.  RTCDataChannel

    interface RTCDataChannel : EventTarget {
        readonly attribute USVString           label;
        readonly attribute boolean             ordered;
        readonly attribute unsigned short?     maxPacketLifeTime;
        readonly attribute unsigned short?     maxRetransmits;
        readonly attribute USVString           protocol;
        readonly attribute boolean             negotiated;
        readonly attribute unsigned short?     id;
        readonly attribute RTCPriorityType     priority;
        readonly attribute RTCDataChannelState readyState;
        readonly attribute unsigned long       bufferedAmount;
                 attribute unsigned long       bufferedAmountLowThreshold;
        [...]
                 attribute DOMString           binaryType;
        [...]
    };

    dictionary RTCDataChannelInit {
        boolean         ordered = true;
        unsigned short  maxPacketLifeTime;
        unsigned short  maxRetransmits;
        USVString       protocol = "";
        boolean         negotiated = false;
        [EnforceRange]
        unsigned short  id;
        RTCPriorityType priority = "low";
    };

  4.9.1.  RTCPriorityType Enum

    enum RTCPriorityType {
      "very-low",
      "low",
      "medium",
      "high"
    };
 */

test(t => {
  const pc = new RTCPeerConnection();
  t.add_cleanup(() => pc.close());

  assert_equals(pc.createDataChannel.length, 1);
  assert_throws(new TypeError(), () => pc.createDataChannel());
}, 'createDataChannel with no argument should throw TypeError');

/*
  6.2.  createDataChannel
    2.  If connection's [[isClosed]] slot is true, throw an InvalidStateError.
 */
test(t => {
  const pc = new RTCPeerConnection();
  pc.close();
  assert_equals(pc.signalingState, 'closed', 'signaling state');
  assert_throws('InvalidStateError', () => pc.createDataChannel(''));
}, 'createDataChannel with closed connection should throw InvalidStateError');

/*
  6.1.  createDataChannel
    4.  Let channel have a [[DataChannelLabel]] internal slot initialized to the value of the
        first argument.
    6.  Let options be the second argument.
    7.  Let channel have an [[MaxPacketLifeTime]] internal slot initialized to
        option's maxPacketLifeTime member, if present, otherwise null.
    8.  Let channel have a [[ReadyState]] internal slot initialized to "connecting".
    9.  Let channel have a [[BufferedAmount]] internal slot initialized to 0.
    10. Let channel have an [[MaxRetransmits]] internal slot initialized to
        option's maxRetransmits member, if present, otherwise null.
    11. Let channel have an [[Ordered]] internal slot initialized to option's
        ordered member.
    12. Let channel have a [[DataChannelProtocol]] internal slot initialized to option's
        protocol member.
    14. Let channel have a [[Negotiated]] internal slot initialized to option's negotiated
        member.
    15. Let channel have an [[DataChannelId]] internal slot initialized to option's id
        member, if it is present and [[Negotiated]] is true, otherwise null.
    17. Let channel have an [[DataChannelPriority]] internal slot initialized to option's
        priority member.
    21. If the [[DataChannelId]] slot is null (due to no ID being passed into
        createDataChannel, or [[Negotiated]] being false), and the DTLS role of the SCTP
        transport has already been negotiated, then initialize [[DataChannelId]] to a value
        generated by the user agent, according to [RTCWEB-DATA-PROTOCOL], and skip
        to the next step. If no available ID could be generated, or if the value of the
        [[DataChannelId]] slot is being used by an existing RTCDataChannel, throw an
        OperationError exception.

        Note
        If the [[DataChannelId]] slot is null after this step, it will be populated once
        the DTLS role is determined during the process of setting an RTCSessionDescription.
    22. If channel is the first RTCDataChannel created on connection, update the
        negotiation-needed flag for connection.


  6.2.  RTCDataChannel

    A RTCDataChannel, created with createDataChannel or dispatched via a
    RTCDataChannelEvent, MUST initially be in the connecting state

    bufferedAmountLowThreshold
      [...] The bufferedAmountLowThreshold is initially zero on each new RTCDataChannel,
      but the application may change its value at any time.

    binaryType
      [...] When a RTCDataChannel object is created, the binaryType attribute MUST
      be initialized to the string "blob".
 */
test(t => {
  const pc = new RTCPeerConnection();
  t.add_cleanup(() => pc.close());

  const dc = pc.createDataChannel('');

  assert_true(dc instanceof RTCDataChannel, 'is RTCDataChannel');
  assert_equals(dc.label, '');
  assert_equals(dc.ordered, true);
  assert_equals(dc.maxPacketLifeTime, null);
  assert_equals(dc.maxRetransmits, null);
  assert_equals(dc.protocol, '');
  assert_equals(dc.negotiated, false);
  // Since no offer/answer exchange has occurred yet, the DTLS role is unknown
  // and so the ID should be null.
  assert_equals(dc.id, null);
  assert_equals(dc.priority, 'low');
  assert_equals(dc.readyState, 'connecting');
  assert_equals(dc.bufferedAmount, 0);
  assert_equals(dc.bufferedAmountLowThreshold, 0);
  assert_equals(dc.binaryType, 'blob');
}, 'createDataChannel attribute default values');

test(t => {
  const pc = new RTCPeerConnection();
  t.add_cleanup(() => pc.close());

  const dc = pc.createDataChannel('test', {
    ordered: false,
    maxRetransmits: 1,
    // Note: maxPacketLifeTime is not set in this test.
    protocol: 'custom',
    negotiated: true,
    id: 3,
    priority: 'high'
  });

  assert_true(dc instanceof RTCDataChannel, 'is RTCDataChannel');
  assert_equals(dc.label, 'test');
  assert_equals(dc.ordered, false);
  assert_equals(dc.maxPacketLifeTime, null);
  assert_equals(dc.maxRetransmits, 1);
  assert_equals(dc.protocol, 'custom');
  assert_equals(dc.negotiated, true);
  assert_equals(dc.id, 3);
  assert_equals(dc.priority, 'high');
  assert_equals(dc.readyState, 'connecting');
  assert_equals(dc.bufferedAmount, 0);
  assert_equals(dc.bufferedAmountLowThreshold, 0);
  assert_equals(dc.binaryType, 'blob');

  const dc2 = pc.createDataChannel('test2', {
    ordered: false,
    maxPacketLifeTime: 42
  });
  assert_equals(dc2.label, 'test2');
  assert_equals(dc2.maxPacketLifeTime, 42);
  assert_equals(dc.maxRetransmits, null);
}, 'createDataChannel with provided parameters should initialize attributes to provided values');

/*
  6.2.  createDataChannel
    4.  Let channel have a [[DataChannelLabel]] internal slot initialized to the value of the
        first argument.

  [ECMA262] 7.1.12. ToString(argument)
    undefined -> "undefined"
    null -> "null"

  [WebIDL] 3.10.15. Convert a DOMString to a sequence of Unicode scalar values
 */
const labels = [
  ['"foo"', 'foo', 'foo'],
  ['null', null, 'null'],
  ['undefined', undefined, 'undefined'],
  ['lone surrogate', '\uD800', '\uFFFD'],
];
for (const [description, label, expected] of labels) {
  test(t => {
    const pc = new RTCPeerConnection;
    t.add_cleanup(() => pc.close());

    const dc = pc.createDataChannel(label);
    assert_equals(dc.label, expected);
  }, `createDataChannel with label ${description} should succeed`);
}

/*
  6.2.  RTCDataChannel
    createDataChannel
      11. Let channel have an [[Ordered]] internal slot initialized to option's
          ordered member.
 */
test(t => {
  const pc = new RTCPeerConnection();
  t.add_cleanup(() => pc.close());

  const dc = pc.createDataChannel('', { ordered: false });
  assert_equals(dc.ordered, false);
}, 'createDataChannel with ordered false should succeed');

// true as the default value of a boolean is confusing because null is converted
// to false while undefined is converted to true.
test(t => {
  const pc = new RTCPeerConnection();
  t.add_cleanup(() => pc.close());

  const dc1 = pc.createDataChannel('', { ordered: null });
  assert_equals(dc1.ordered, false);
  const dc2 = pc.createDataChannel('', { ordered: undefined });
  assert_equals(dc2.ordered, true);
}, 'createDataChannel with ordered null/undefined should succeed');

/*
  6.2.  RTCDataChannel
    createDataChannel
      7.  Let channel have an [[MaxPacketLifeTime]] internal slot initialized to
          option's maxPacketLifeTime member, if present, otherwise null.
 */
test(t => {
  const pc = new RTCPeerConnection;
  t.add_cleanup(() => pc.close());

  const dc = pc.createDataChannel('', { maxPacketLifeTime: 0 });
  assert_equals(dc.maxPacketLifeTime, 0);
}, 'createDataChannel with maxPacketLifeTime 0 should succeed');

/*
  6.2.  RTCDataChannel
    createDataChannel
      10. Let channel have an [[MaxRetransmits]] internal slot initialized to
          option's maxRetransmits member, if present, otherwise null.
 */
test(t => {
  const pc = new RTCPeerConnection;
  t.add_cleanup(() => pc.close());

  const dc = pc.createDataChannel('', { maxRetransmits: 0 });
  assert_equals(dc.maxRetransmits, 0);
}, 'createDataChannel with maxRetransmits 0 should succeed');

/*
  6.2.  createDataChannel
    18. If both [[MaxPacketLifeTime]] and [[MaxRetransmits]] attributes are set (not null),
        throw a TypeError.
 */
test(t => {
  const pc = new RTCPeerConnection;
  t.add_cleanup(() => pc.close());

  pc.createDataChannel('', {
    maxPacketLifeTime: undefined,
    maxRetransmits: undefined
  });
}, 'createDataChannel with both maxPacketLifeTime and maxRetransmits undefined should succeed');

test(t => {
  const pc = new RTCPeerConnection;
  t.add_cleanup(() => pc.close());

  assert_throws(new TypeError(), () => pc.createDataChannel('', {
    maxPacketLifeTime: 0,
    maxRetransmits: 0
  }));
  assert_throws(new TypeError(), () => pc.createDataChannel('', {
    maxPacketLifeTime: 42,
    maxRetransmits: 42
  }));
}, 'createDataChannel with both maxPacketLifeTime and maxRetransmits should throw TypeError');

/*
  6.2.  RTCDataChannel
    createDataChannel
      12. Let channel have a [[DataChannelProtocol]] internal slot initialized to option's
          protocol member.
 */
const protocols = [
  ['"foo"', 'foo', 'foo'],
  ['null', null, 'null'],
  ['undefined', undefined, ''],
  ['lone surrogate', '\uD800', '\uFFFD'],
];
for (const [description, protocol, expected] of protocols) {
  test(t => {
    const pc = new RTCPeerConnection;
    t.add_cleanup(() => pc.close());

    const dc = pc.createDataChannel('', { protocol });
    assert_equals(dc.protocol, expected);
  }, `createDataChannel with protocol ${description} should succeed`);
}

/*
  6.2.  RTCDataChannel
    createDataChannel
      20. If [[DataChannelId]] is equal to 65535, which is greater than the maximum allowed
          ID of 65534 but still qualifies as an unsigned short, throw a TypeError.
 */
for (const id of [0, 1, 65534]) {
  test(t => {
    const pc = new RTCPeerConnection();
    t.add_cleanup(() => pc.close());

    const dc = pc.createDataChannel('', { 'negotiated': true, 'id': id });
    assert_equals(dc.id, id);
  }, `createDataChannel with id ${id} should succeed`);
}

for (const id of [-1, 65535, 65536]) {
  test(t => {
    const pc = new RTCPeerConnection();
    t.add_cleanup(() => pc.close());

    assert_throws(new TypeError(), () => pc.createDataChannel('',
        { 'negotiated': true, 'id': id }));
  }, `createDataChannel with id ${id} should throw TypeError`);
}

/*
  6.2.  RTCDataChannel
    createDataChannel
      17. Let channel have an [[DataChannelPriority]] internal slot initialized to option's
          priority member.
 */
test(t => {
  const pc = new RTCPeerConnection();
  t.add_cleanup(() => pc.close());

  const dc = pc.createDataChannel('', { priority: 'high' });
  assert_equals(dc.priority, 'high');
}, 'createDataChannel with priority "high" should succeed');

test(t => {
  const pc = new RTCPeerConnection();
  t.add_cleanup(() => pc.close());

  assert_throws(new TypeError(),
    () => pc.createDataChannel('', { priority: 'invalid' }));
}, 'createDataChannel with invalid priority should throw TypeError');

/*
  6.2.  createDataChannel
    5.  If [[DataChannelLabel]] is longer than 65535 bytes, throw a TypeError.
 */
test(t => {
  const pc = new RTCPeerConnection();
  t.add_cleanup(() => pc.close());

  assert_throws(new TypeError(), () =>
    pc.createDataChannel('l'.repeat(65536)));

  assert_throws(new TypeError(), () =>
    pc.createDataChannel('l'.repeat(65536), {
      negotiated: true,
      id: 42
    }));
}, 'createDataChannel with too long label should throw TypeError');

test(t => {
  const pc = new RTCPeerConnection();
  t.add_cleanup(() => pc.close());

  assert_throws(new TypeError(), () =>
    pc.createDataChannel('\u00b5'.repeat(32768)));

  assert_throws(new TypeError(), () =>
    pc.createDataChannel('\u00b5'.repeat(32768), {
      negotiated: true,
      id: 42
    }));
}, 'createDataChannel with too long label (2 byte unicode) should throw TypeError');

/*
  6.2.  label
        [...] Scripts are allowed to create multiple RTCDataChannel objects with the same label.
        [...]
 */
test(t => {
  const pc = new RTCPeerConnection();
  t.add_cleanup(() => pc.close());

  const label = 'test';

  pc.createDataChannel(label);
  pc.createDataChannel(label);
}, 'createDataChannel with same label used twice should not throw');

/*
  6.2.  createDataChannel
    13. If [[DataChannelProtocol]] is longer than 65535 bytes long, throw a TypeError.
 */

test(t => {
  const pc = new RTCPeerConnection;
  t.add_cleanup(() => pc.close());
  const channel = pc.createDataChannel('', { negotiated: true, id: 42 });
  assert_equals(channel.negotiated, true);
}, 'createDataChannel with negotiated true and id should succeed');

test(t => {
  const pc = new RTCPeerConnection();
  t.add_cleanup(() => pc.close());

  assert_throws(new TypeError(), () =>
    pc.createDataChannel('', {
      protocol: 'p'.repeat(65536)
    }));

  assert_throws(new TypeError(), () =>
    pc.createDataChannel('', {
      protocol: 'p'.repeat(65536),
      negotiated: true,
      id: 42
    }));
}, 'createDataChannel with too long protocol should throw TypeError');

test(t => {
  const pc = new RTCPeerConnection();
  t.add_cleanup(() => pc.close());

  assert_throws(new TypeError(), () =>
    pc.createDataChannel('', {
      protocol: '\u00b6'.repeat(32768)
    }));

  assert_throws(new TypeError(), () =>
    pc.createDataChannel('', {
      protocol: '\u00b6'.repeat(32768),
      negotiated: true,
      id: 42
    }));
}, 'createDataChannel with too long protocol (2 byte unicode) should throw TypeError');

test(t => {
  const pc = new RTCPeerConnection();
  t.add_cleanup(() => pc.close());

  const label = 'l'.repeat(65535);
  const protocol = 'p'.repeat(65535);

  const dc = pc.createDataChannel(label, {
    protocol: protocol
  });

  assert_equals(dc.label, label);
  assert_equals(dc.protocol, protocol);
}, 'createDataChannel with maximum length label and protocol should succeed');

/*
  6.2   createDataChannel
    15. Let channel have an [[DataChannelId]] internal slot initialized to option's id member,
        if it is present and [[Negotiated]] is true, otherwise null.

        NOTE
        This means the id member will be ignored if the data channel is negotiated in-band; this
        is intentional. Data channels negotiated in-band should have IDs selected based on the
        DTLS role, as specified in [RTCWEB-DATA-PROTOCOL].
 */
test(t => {
  const pc = new RTCPeerConnection;
  t.add_cleanup(() => pc.close());

  const dc = pc.createDataChannel('', {
    negotiated: false,
  });
  assert_equals(dc.negotiated, false, 'Expect dc.negotiated to be false');
}, 'createDataChannel with negotiated false should succeed');

test(t => {
  const pc = new RTCPeerConnection;
  t.add_cleanup(() => pc.close());

  const dc = pc.createDataChannel('', {
    negotiated: false,
    id: 42
  });
  assert_equals(dc.negotiated, false, 'Expect dc.negotiated to be false');
  assert_equals(dc.id, null, 'Expect dc.id to be ignored (null)');
}, 'createDataChannel with negotiated false and id 42 should ignore the id');

/*
  6.2.  createDataChannel
    16. If [[Negotiated]] is true and [[DataChannelId]] is null, throw a TypeError.
 */
test(t => {
  const pc = new RTCPeerConnection();
  t.add_cleanup(() => pc.close());

  assert_throws(new TypeError(), () =>
    pc.createDataChannel('test', {
      negotiated: true
    }));
}, 'createDataChannel with negotiated true and id not defined should throw TypeError');

/*
  4.4.1.6.  Set the RTCSessionSessionDescription
    2.2.6.  If description is of type "answer" or "pranswer", then run the
            following steps:
      3.    If description negotiates the DTLS role of the SCTP transport, and there is an
            RTCDataChannel with a null id, then generate an ID according to
            [RTCWEB-DATA-PROTOCOL]. [...]

  6.1.  createDataChannel
    21. If the [[DataChannelId]] slot is null (due to no ID being passed into
        createDataChannel, or [[Negotiated]] being false), and the DTLS role of the SCTP
        transport has already been negotiated, then initialize [[DataChannelId]] to a value
        generated by the user agent, according to [RTCWEB-DATA-PROTOCOL], and skip
        to the next step. If no available ID could be generated, or if the value of the
        [[DataChannelId]] slot is being used by an existing RTCDataChannel, throw an
        OperationError exception.

        Note
        If the [[DataChannelId]] slot is null after this step, it will be populated once
        the DTLS role is determined during the process of setting an RTCSessionDescription.
 */
promise_test(async t => {
  const pc1 = new RTCPeerConnection();
  const pc2 = new RTCPeerConnection();
  t.add_cleanup(() => pc1.close());
  t.add_cleanup(() => pc2.close());

  const negotiatedDc = pc1.createDataChannel('negotiated-channel', {
    negotiated: true,
    id: 42,
  });
  assert_equals(negotiatedDc.id, 42, 'Expect negotiatedDc.id to be 42');

  const dc1 = pc1.createDataChannel('channel');
  assert_equals(dc1.id, null, 'Expect initial id to be null');

  const offer = await pc1.createOffer();
  await Promise.all([pc1.setLocalDescription(offer), pc2.setRemoteDescription(offer)]);
  const answer = await pc2.createAnswer();
  await pc1.setRemoteDescription(answer);

  assert_not_equals(dc1.id, null,
    'Expect dc1.id to be assigned after remote description has been set');

  assert_greater_than_equal(dc1.id, 0,
    'Expect dc1.id to be set to valid unsigned short');

  assert_less_than(dc1.id, 65535,
    'Expect dc1.id to be set to valid unsigned short');

  const dc2 = pc1.createDataChannel('channel');

  assert_not_equals(dc2.id, null,
    'Expect dc2.id to be assigned after remote description has been set');

  assert_greater_than_equal(dc2.id, 0,
    'Expect dc2.id to be set to valid unsigned short');

  assert_less_than(dc2.id, 65535,
    'Expect dc2.id to be set to valid unsigned short');

  assert_not_equals(dc2, dc1,
    'Expect channels created from same label to be different');

  assert_equals(dc2.label, dc1.label,
    'Expect different channels can have the same label but different id');

  assert_not_equals(dc2.id, dc1.id,
    'Expect different channels can have the same label but different id');

  assert_equals(negotiatedDc.id, 42,
    'Expect negotiatedDc.id to be 42 after remote description has been set');
}, 'Channels created (after setRemoteDescription) should have id assigned');

test(t => {
  const pc = new RTCPeerConnection();
  t.add_cleanup(() => pc.close());

  const dc1 = pc.createDataChannel('channel-1', {
    negotiated: true,
    id: 42,
  });
  assert_equals(dc1.id, 42,
    'Expect dc1.id to be 42');

  const dc2 = pc.createDataChannel('channel-2', {
    negotiated: true,
    id: 43,
  });
  assert_equals(dc2.id, 43,
    'Expect dc2.id to be 43');

  assert_throws('OperationError', () =>
    pc.createDataChannel('channel-3', {
      negotiated: true,
      id: 42,
    }));

}, 'Reusing a data channel id that is in use should throw OperationError');

// We've seen implementations behaving differently before and after the connection has been
// established.
promise_test(async t => {
  const pc1 = new RTCPeerConnection();
  const pc2 = new RTCPeerConnection();
  t.add_cleanup(() => pc1.close());
  t.add_cleanup(() => pc2.close());

  const dc1 = pc1.createDataChannel('channel-1', {
    negotiated: true,
    id: 42,
  });
  assert_equals(dc1.id, 42, 'Expect dc1.id to be 42');

  const dc2 = pc1.createDataChannel('channel-2', {
    negotiated: true,
    id: 43,
  });
  assert_equals(dc2.id, 43, 'Expect dc2.id to be 43');

  const offer = await pc1.createOffer();
  await Promise.all([pc1.setLocalDescription(offer), pc2.setRemoteDescription(offer)]);
  const answer = await pc2.createAnswer();
  await pc1.setRemoteDescription(answer);

  assert_equals(dc1.id, 42, 'Expect dc1.id to be 42');

  assert_equals(dc2.id, 43, 'Expect dc2.id to be 43');

  assert_throws('OperationError', () =>
    pc1.createDataChannel('channel-3', {
      negotiated: true,
      id: 42,
    }));
}, 'Reusing a data channel id that is in use (after setRemoteDescription) should throw ' +
   'OperationError');

promise_test(async t => {
  const pc1 = new RTCPeerConnection();
  const pc2 = new RTCPeerConnection();
  t.add_cleanup(() => pc1.close());
  t.add_cleanup(() => pc2.close());

  const dc1 = pc1.createDataChannel('channel-1');

  const offer = await pc1.createOffer();
  await Promise.all([pc1.setLocalDescription(offer), pc2.setRemoteDescription(offer)]);
  const answer = await pc2.createAnswer();
  await pc1.setRemoteDescription(answer);

  assert_not_equals(dc1.id, null,
    'Expect dc1.id to be assigned after remote description has been set');

  assert_throws('OperationError', () =>
    pc1.createDataChannel('channel-2', {
      negotiated: true,
      id: dc1.id,
    }));
}, 'Reusing a data channel id that is in use (after setRemoteDescription, negotiated via DCEP) ' +
  'should throw OperationError');

// Based on https://bugzilla.mozilla.org/show_bug.cgi?id=1441723
promise_test(async t => {
  const pc1 = new RTCPeerConnection();
  const pc2 = new RTCPeerConnection();
  t.add_cleanup(() => pc1.close());
  t.add_cleanup(() => pc2.close());

  await createDataChannelPair(pc1, pc2);

  const dc = pc1.createDataChannel('');
  assert_equals(dc.readyState, 'connecting', 'Channel should be in the connecting state');
}, 'New data channel should be in the connecting state after creation (after connection ' +
  'establishment)');

/*
  Untestable
    6.1.  createDataChannel
      19. If a setting, either [[MaxPacketLifeTime]] or [[MaxRetransmits]], has been set to
          indicate unreliable mode, and that value exceeds the maximum value supported
          by the user agent, the value MUST be set to the user agents maximum value.

      23. Return channel and continue the following steps in parallel.
      24. Create channel's associated underlying data transport and configure
          it according to the relevant properties of channel.

  Tested in RTCPeerConnection-onnegotiationneeded.html
    22. If channel is the first RTCDataChannel created on connection, update the
        negotiation-needed flag for connection.

  Tested in RTCDataChannel-id.html
    - Odd/even rules for '.id'

  Tested in RTCDataChannel-dcep.html
    - Transmission of '.label' and further options
*/
</script>