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sammy-SC
a206fbd2fd
## Summary
Prefer `getChildrenAsJSX` or `toMatchRenderedOutput` over `getChildren`.
Use `dangerouslyGetChildren` if you really need to (e.g. for `toBe`
assertions).
Prefer `getPendingChildrenAsJSX` over `getPendingChildren`. Use
`dangerouslyGetPendingChildren` if you really need to (e.g. for `toBe`
assertions).
`ReactNoop.getChildren` contains the fibers as non-enumerable
properties. If you pass the children to `toEqual` and have a mismatch,
Jest performance is very poor (to the point of causing out-of-memory
crashes e.g.
https://app.circleci.com/pipelines/github/facebook/react/38084/workflows/02ca0cbb-bab4-4c19-8d7d-ada814eeebb9/jobs/624297/parallel-runs/5?filterBy=ALL&invite=true#step-106-27).
Mismatches can sometimes be intended e.g. on gated tests.
Instead, I converted almost all of the `toEqual` assertions to
`toMatchRenderedOutput` assertions or compare the JSX instead. For
ReactNoopPersistent we still use `getChildren` since we have assertions
on referential equality. `toMatchRenderedOutput` is more accurate in
some instances anyway. I highlighted some of those more accurate
assertions in review-comments.
## How did you test this change?
- [x] `CIRCLE_NODE_TOTAL=20 CIRCLE_NODE_INDEX=5 yarn test
-r=experimental --env=development --ci`: Can take up to 350s (and use up
to 7GB of memory) on `main` but 11s on this branch
- [x] No more slow `yarn test` parallel runs of `yarn_test` jobs (the
steps in these runs should take <1min but sometimes they take 3min and
end with OOM like
https://app.circleci.com/pipelines/github/facebook/react/38084/workflows/02ca0cbb-bab4-4c19-8d7d-ada814eeebb9/jobs/624258/parallel-runs/5?filterBy=ALL:
Looks good with a sample size of 1
https://app.circleci.com/pipelines/github/facebook/react/38110/workflows/745109a2-b86b-429f-8c01-9b23a245417a/jobs/624651
DiffTrain build for [3ff1540e9b](https://github.com/facebook/react/commit/3ff1540e9bbe30aae52e2c9ab61c843bd0c94237)
[View git log for this commit](https://github.com/facebook/react/commits/3ff1540e9bbe30aae52e2c9ab61c843bd0c94237)