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Use friendly error messages in "x is undefined" cases

See original GitHub issue

TypeError: Cannot read property '_timing' of undefined
  File "/usr/lib/node_modules/lighthouse/lighthouse-core/audits/time-to-first-byte.js", line 29, col 26, in Function.caclulateTTFB
    const timing = record._timing;
  File "/usr/lib/node_modules/lighthouse/lighthouse-core/audits/time-to-first-byte.js", line 47, col 33, in artifacts.requestNetworkRecords.then
    const ttfb = TTFBMetric.caclulateTTFB(finalUrlRequest);
  File "internal/process/next_tick.js", line 135, col 7, in process._tickDomainCallback

https://sentry.io/google-lighthouse/lighthouse/issues/407357986/

Issue Analytics

State:
Created 6 years ago
Comments:5 (1 by maintainers)

Top GitHub Comments

2reactions

patrickhulcecommented, Nov 22, 2017

Yeah basically the bug is on the error message, not the error existing. Not much we can do in that audit if we couldn’t find the request 😃

IMO we should try to minimize the debugStrings in the report that are of the form ‘blah of undefined’ and try to say what happened, like “Unable to identify the main resource” or something

0reactions

brendankennycommented, Apr 25, 2019

Well we have better network request fallbacks for timing info, so hopefully we have more intelligible error messages if anyone is still hitting this case 😃

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