An error occurred in Firefox Profiler while analysing a profile

[mayankleoboy]

I had profiled https://battle.modez.pro/ , and was looking at the profile.
Suddenly got this error:

Uh oh, some unknown error happened in profiler.firefox.com.

Error: Expected an item to exist, and it was undefined..

Please report this issue to the developers, including the full error as displayed in the Developer Tools’ Web Console.

Error in console:
10:14:49.724 injected firefox content.js:142:11
10:14:49.858 Successfully compiled asm.js code (total compilation time 27ms) zee-worker.js
10:15:07.345
Error: Expected an item to exist, and it was undefined.
h flow.js:182
render SampleTooltipContents.js:136
React 10
react-dom.production.min.js:188:119
React 11
10:15:07.345
An unhandled error was thrown in a React component. Error: Expected an item to exist, and it was undefined.
h flow.js:182
render SampleTooltipContents.js:136
React 10

Gk@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:133:53375
div
Kb@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:114:44368
div
Hk@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:133:54068
@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:117:15904
div
Ax@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:137:281
@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:117:15904
c@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:2:24380
div
div
li
PS@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:137:70940
c@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:2:24380
ol
KS@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:137:78856
li
YS@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:137:81848
c@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:2:24380
ol
KS@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:137:78856
div
div
div
lB@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:137:94960
div
oB@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:137:89197
c@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:2:24380
vB@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:137:113962
@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:117:15904
c@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:2:24380
LB@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:137:123460
c@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:2:24380
div
s@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:200:573772
div
t@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:200:575421
div
div
tk@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:133:27292
YB@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:137:126842
c@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:2:24380
UI@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:137:158880
c@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:2:24380
jm@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:111:3131
c@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:2:24380
div
QB@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:137:128910
c@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:2:24380
cg@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:111:19405
ug
de@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:2:17306
ce@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:2:17219
g_@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:137:179088
c@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:2:24380
st@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:2:22644
cg@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:111:19405
dg
v_@https://profiler.firefox.com/main.1cb3af3791ee766fff86.bundle.js:137:180180 ErrorBoundary.js:43:12
10:15:21.681
Unknown property ‘-moz-user-focus’. Declaration dropped. from-browser:1:604
10:15:21.684
Unknown property ‘-moz-user-focus’. Declaration dropped. from-browser:1:1497
10:15:21.684
Unknown property ‘-moz-user-focus’. Declaration dropped. from-browser:1:349
10:15:21.685
Unknown property ‘-moz-user-focus’. Declaration dropped.

┆Issue is synchronized with this Jira Task

[julienw]

This happens at

profiler/src/components/shared/SampleTooltipContents.js

Lines 132 to 139 in acd55ea

	if (hasSamples) {
	const stack = getFuncNamesAndOriginsForPath(
	convertStackToCallNodeAndCategoryPath(
	rangeFilteredThread,
	ensureExists(stackIndex)
	),
	rangeFilteredThread
	);

It would be good to check for the existence of the stackIndex in the if condition instead of using ensureExists.