TypeError: Cannot destructure property `startBufferRow` of 'undefined' or 'null'

[kuychaco]

Got this error when trying to view the PR pane item "Files" tab for apiaryio/metamorphoses#88 (pulled from list here https://github.com/github/analytics/pull/454)

[annthurium]

Trying to repro this and running into that graphQL bug:

@kuychaco did you happen to come across any other examples?

[vanessayuenn]

Came across this while QA-ing for #2005 too.

Steps to reproduce:

1. open a PR on dotcom
2. make an few inline comments in a file that's large enough to be diff-gated in atom
3. expand collapsed filepatch in PR view in atom

[kuychaco]

Came across this while QA-ing for #2005 too.

@vanessayuenn did you see this exact error (Cannot destructure property startBufferRow from 'undefined' or 'null') or was it the offset error that you're putting in a fix for?

I can't seem to repro this on our all/review-comments branch. In which case I might just close this issue unless you happened to be able to repro it

[vanessayuenn]

@kuychaco it was Cannot destructure property offset from 'undefined' or 'null' which occurred one line below where the error you encountered was thrown. I believe they're stemmed from the same issue -- we forgot to reset diffRowOffsetIndices upon expanding a large file patch that was "skipped" when we process it in the first run.

I'm not able to repro the exact bug you're describing, even in a branch without the fix we put in, too.