timings, too long
<link rel="help" href="https://w3c.github.io/webvtt/#collect-a-webvtt-timestamp">

assert_equals(cues.length, 2);

assert_equals(cues[0].text, 'text0');
assert_equals(cues[0].startTime, 0);
assert_equals(cues[0].endTime, 1);

assert_equals(cues[1].text, 'text1');
assert_equals(cues[1].startTime, 0);
assert_equals(cues[1].endTime, 1);

===
WEBVTT

000:00:00.000 --> 00:00:01.000
text0

00::00:00.000 --> 00:00:01.000
invalid

00:000:00.000 --> 00:00:01.000
invalid

00:00::00.000 --> 00:00:01.000
invalid

00:00:000.000 --> 00:00:01.000
invalid

00:00:00..000 --> 00:00:01.000
invalid

00:00:00.0000 --> 00:00:01.000
invalid

00:00.0000 --> 00:00:01.000
invalid

000:00.000 --> 00:01.000
invalid

00::00.000 --> 00:01.000
invalid

00:000.000 --> 00:01.000
invalid

00:00..000 --> 00:01.000
invalid

00:00.0000 --> 00:01.000
invalid

00:00.000 --> 000:01.000
invalid

00:00:00.000 --> 000:00:01.000
text1