test AudioContext state updates with suspend() shortly after construction
Differential Revision: https://phabricator.services.mozilla.com/D79057
bugzilla-url: https://bugzilla.mozilla.org/show_bug.cgi?id=1644647
gecko-commit: cbbe8b775137d7321ed0128455694c67e55a7e2f
gecko-integration-branch: autoland
gecko-reviewers: padenot
diff --git a/webaudio/the-audio-api/the-audiocontext-interface/suspend-after-construct.html b/webaudio/the-audio-api/the-audiocontext-interface/suspend-after-construct.html
new file mode 100644
index 0000000..596a825
--- /dev/null
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+<!doctype html>
+<title>Test AudioContext state updates with suspend() shortly after
+ construction</title>
+<script src=/resources/testharness.js></script>
+<script src=/resources/testharnessreport.js></script>
+<script>
+// A separate async_test is used for tracking state change counts so that it
+// can report excess changes after the promise_test for the iteration has
+// completed.
+const changeCountingTest = async_test('State change counting');
+
+const doTest = async (testCount) => {
+ const ctx = new AudioContext();
+ // Explicitly resume to get a promise to indicate whether the context
+ // successfully started running.
+ const resume = ctx.resume();
+ const suspend = ctx.suspend();
+ let stateChangesDone = new Promise((resolve) => {
+ ctx.onstatechange = () => {
+ ++ctx.stateChangeCount;
+ changeCountingTest.step(() => {
+ assert_less_than_equal(ctx.stateChangeCount,
+ ctx.expectedStateChangeCount,
+ `ctx ${testCount} state change count.`);
+ assert_equals(ctx.state, ctx.expectedState, `ctx ${testCount} state`);
+ });
+ if (ctx.stateChangeCount == ctx.totalStateChangeCount) {
+ resolve();
+ }
+ };
+ });
+ ctx.stateChangeCount = 0;
+ ctx.expectedStateChangeCount = 1;
+ ctx.expectedState = 'running';
+ ctx.totalStateChangeCount = 2;
+ let resumeState = 'pending';
+ resume.then(() => {
+ resumeState = 'fulfilled';
+ assert_equals(ctx.state, 'running', 'state on resume fulfilled.');
+ }).catch(() => {
+ // The resume() promise may be rejected if "Attempt to acquire system
+ // resources" fails. The spec does not discuss the possibility of a
+ // subsequent suspend causing such a failure, but accept this as a
+ // reasonable behavior.
+ resumeState = 'rejected';
+ assert_equals(ctx.state, 'suspended', 'state on resume rejected.');
+ assert_equals(ctx.stateChangeCount, 0);
+ ctx.expectedStateChangeCount = 0;
+ stateChangesDone = Promise.resolve();
+ });
+ suspend.then(() => {
+ assert_not_equals(resumeState, 'pending',
+ 'resume promise should settle before suspend promise.')
+ if (resumeState == 'fulfilled') {
+ ++ctx.expectedStateChangeCount;
+ }
+ ctx.expectedState = 'suspended';
+ assert_equals(ctx.state, 'suspended', 'state on suspend fulfilled.');
+ });
+ await resume;
+ await suspend;
+ await stateChangesDone;
+};
+
+// Repeat the test because Gecko uses different code when there is more than
+// one AudioContext. The third run provides time to check that no further
+// state changes from the second run are pending.
+for (const testCount of [1, 2, 3]) {
+ promise_test(() => { return doTest(testCount); }, `Iteration ${testCount}`);
+}
+promise_test(async () => changeCountingTest.done(), 'Stop waiting');
+</script>
