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ReactDefaultPerf.printWasted() doesn't work

See original GitHub issue

Calling ReactDefaultPerf.printWasted() results in:

Uncaught TypeError: Cannot read property 'forEach' of undefined
writes.(anonymous function).forEach @ ReactDefaultPerfAnalysis.js:195
Object.keys.forEach @ ReactDefaultPerfAnalysis.js:192
getUnchangedComponents @ ReactDefaultPerfAnalysis.js:191
getInclusiveSummary @ ReactDefaultPerfAnalysis.js:139
ReactDefaultPerf.getMeasurementsSummaryMap @ ReactDefaultPerf.js:118
ReactDefaultPerf.printWasted @ ReactDefaultPerf.js:133

(this is on a page internally at Facebook so I assume it’s a fairly recent React version)

Issue Analytics

State:
Created 8 years ago
Comments:16 (11 by maintainers)

Top GitHub Comments

3reactions

sverrejohcommented, Apr 10, 2016

Yes. ReactPerf.start(), ReactPerf.stop() and the rest of the Perf API works, for example ReactPerf.printExclusive(), but not ReactPerf.printWasted().

I changed over to my 0.14.7 branch, and there everything works like it should, and I double checked that both ReactPerf and React was on 15.0.1.

I can dig around a bit more if this isn’t anything known.

0reactions

gaearoncommented, Apr 14, 2016

Thank you, this is very helpful! I’ll dig into it and see if I can repro this given the new info.

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