Marker that have no duration should be open ended on the unfinished side

[julienw]

see example at https://share.firefox.dev/3CryCa1

There's some code to handle that already (it's working for preview selections) but obviously it doesn't work here.

┆Issue is synchronized with this Jira Task

[mstange]

The code which creates interval markers from start + end markers makes it so that all interval markers have a non-null end time, by falling back to threadRange.end:

profiler/src/profile-logic/marker-data.js

Lines 987 to 1007 in 28e880e

	const endOfThread = threadRange.end;
	// Loop over "start" markers without any "end" markers.
	for (const markerBucket of openIntervalMarkers.values()) {
	for (const startIndex of markerBucket) {
	const start = ensureExists(
	rawMarkers.startTime[startIndex],
	'Encountered a marker without a startTime. Eventually this needs to be handled ' +
	'for phase-style markers.'
	);
	addMarker([startIndex], {
	start,
	end: Math.max(endOfThread, start),
	name: stringTable.getString(rawMarkers.name[startIndex]),
	data: rawMarkers.data[startIndex],
	category: rawMarkers.category[startIndex],
	threadId: rawMarkers.threadId ? rawMarkers.threadId[startIndex] : null,
	incomplete: true,
	});
	}
	}

I think the derived markers don't carry any information which says "the start or end time for this marker wasn't present, pretend this marker goes beyond the start/end of the profile".

[julienw]

We have the incomplete: true boolean, but we don't know which side it's open-ended indeed.

[julienw]

it would probably be good to set it to incomplete: 'start' | 'end' | 'both', and then use it when drawing.