Allow RTCDTMFToneChangeEvents to fire up to 1ms early.
Firefox's timer implementation allows events to fire 250μs early. Instead of
using a non-fuzzy timer in Firefox (may cause extra wakeups) or an artificial
extra delay on every dtmf event, relax the test case a bit.
Differential Revision: https://phabricator.services.mozilla.com/D201821
bugzilla-url: https://bugzilla.mozilla.org/show_bug.cgi?id=1785418
gecko-commit: 8175af8c6fb443418b4fb401b5a2ab282ed73846
gecko-reviewers: bwc
diff --git a/webrtc/RTCDTMFSender-helper.js b/webrtc/RTCDTMFSender-helper.js
index 4316c38..2346560 100644
--- a/webrtc/RTCDTMFSender-helper.js
+++ b/webrtc/RTCDTMFSender-helper.js
@@ -117,10 +117,12 @@
assert_equals(dtmfSender.toneBuffer, expectedToneBuffer,
`Expect dtmfSender.toneBuffer to be updated to ${expectedToneBuffer}`);
- // We check that the cumulative delay is at least the expected one, but
- // system load may cause random delays, so we do not put any
- // realistic upper bound on the timing of the events.
- assert_between_inclusive(Date.now() - start, expectedTime,
+ // We check that the cumulative delay is at least the expected one.
+ // Note that as a UA optimization events can fire a bit (<1ms) early,
+ // and system load may cause random delays. We therefore allow events
+ // to be 1ms early and do not put any realistic expectation on the upper
+ // bound of their timing.
+ assert_between_inclusive(Date.now() - start, Math.max(0, expectedTime - 1),
expectedTime + 4000,
`Expect tonechange event for "${tone}" to be fired approximately after ${expectedTime} milliseconds`);
if (cumulativeToneChanges.length === 0) {
