| <!doctype html> |
| <html> |
| <head> |
| <meta charset="utf-8"> |
| <title>MediaStreamTrackState enum: readyState only ever returns "live" or "ended"</title> |
| <script src="../../resources/testharness.js"></script> |
| <script src="../../resources/testharnessreport.js"></script> |
| <script> |
| // MediaCapture-Main §"MediaStreamTrackState" enum: |
| // https://w3c.github.io/mediacapture-main/#dom-mediastreamtrackstate |
| // |
| // enum MediaStreamTrackState { |
| // "live", |
| // "ended" |
| // }; |
| // |
| // MediaStreamTrack.readyState (a MediaStreamTrackState getter) must |
| // return only one of these two values. There is no script API to "prove" |
| // the enum is closed (we can't enumerate the enum from script), but we |
| // can assert that every observable transition produces a value in the |
| // allowed set — which is the strongest assertion script-side testing |
| // supports for an IDL enum. |
| |
| const VALID = ["live", "ended"]; |
| |
| function assertValidState(track, label) { |
| assert_in_array(track.readyState, VALID, |
| `${label}: readyState is one of ${JSON.stringify(VALID)}`); |
| } |
| |
| promise_test(async test => { |
| // Newly created from getUserMedia. |
| const stream = await navigator.mediaDevices.getUserMedia({ audio: true, video: true }); |
| test.add_cleanup(() => stream.getTracks().forEach(t => t.stop())); |
| |
| for (const t of stream.getTracks()) |
| assertValidState(t, `fresh ${t.kind} track`); |
| |
| // After stop(). |
| for (const t of stream.getTracks()) { |
| t.stop(); |
| assertValidState(t, `stopped ${t.kind} track`); |
| assert_equals(t.readyState, "ended", "stopped track is in 'ended' state"); |
| } |
| }, "readyState is in MediaStreamTrackState enum after creation and after stop()"); |
| |
| promise_test(async test => { |
| // Clones of live and ended tracks must also yield valid states. |
| const stream = await navigator.mediaDevices.getUserMedia({ video: true }); |
| test.add_cleanup(() => stream.getTracks().forEach(t => t.stop())); |
| const original = stream.getVideoTracks()[0]; |
| |
| const cloneOfLive = original.clone(); |
| test.add_cleanup(() => cloneOfLive.stop()); |
| assertValidState(cloneOfLive, "clone of live track"); |
| assert_equals(cloneOfLive.readyState, "live", |
| "clone of a live track is also live"); |
| |
| original.stop(); |
| const cloneOfEnded = original.clone(); |
| assertValidState(cloneOfEnded, "clone of ended track"); |
| assert_equals(cloneOfEnded.readyState, "ended", |
| "clone of an ended track is also ended"); |
| }, "readyState is in MediaStreamTrackState enum after cloning live and ended tracks"); |
| |
| promise_test(async test => { |
| // Verify that JSON serialization round-trips the enum string verbatim |
| // (no extra modifier characters or stringification artifacts that |
| // would imply a different underlying type). |
| const stream = await navigator.mediaDevices.getUserMedia({ audio: true }); |
| test.add_cleanup(() => stream.getTracks().forEach(t => t.stop())); |
| const track = stream.getAudioTracks()[0]; |
| |
| const round = JSON.parse(JSON.stringify({ s: track.readyState })); |
| assert_equals(typeof round.s, "string", |
| "readyState round-trips as a string"); |
| assert_in_array(round.s, VALID, |
| "readyState round-trip value is in the spec-mandated enum set"); |
| }, "readyState stringifies and round-trips as an enum-set value"); |
| </script> |
| </head> |
| <body></body> |
| </html> |
