* Jest + test renderer helpers for concurrent mode
Most of our concurrent React tests use the noop renderer. But most
of those tests don't test the renderer API, and could instead be
written with the test renderer. We should switch to using the test
renderer whenever possible, because that's what we expect product devs
and library authors to do. If test renderer is sufficient for writing
most React core tests, it should be sufficient for others, too. (The
converse isn't true but we should aim to dogfood test renderer as much
as possible.)
This PR adds a new package, jest-react (thanks @cpojer). I've moved
our existing Jest matchers into that package and added some new ones.
I'm not expecting to figure out the final API in this PR. My goal is
to land something good enough that we can start dogfooding in www.
TODO: Continue migrating Suspense tests, decide on better API names
* Add additional invariants to prevent common errors
- Errors if user attempts to flush when log of yields is not empty
- Throws if argument passed to toClearYields is not ReactTestRenderer
* Better method names
- toFlushAll -> toFlushAndYield
- toFlushAndYieldThrough ->
- toClearYields -> toHaveYielded
Also added toFlushWithoutYielding
* Fix jest-react exports
* Tweak README
Adds custom Jest matchers that help with writing async tests:
- `toFlushThrough`
- `toFlushAll`
- `toFlushAndThrow`
- `toClearYields`
Each one accepts an array of expected yielded values, to prevent
false negatives.
Eventually I imagine we'll want to publish this on npm.
This is a leftover from #13161 that I forgot to include.
It ensures we don't accidentally write code in the old way and end up passing the stack twice.
* Use %s in the console calls
* Add shared/warningWithStack
* Convert some warning callsites to warningWithStack
* Use warningInStack in shared utilities and remove unnecessary checks
* Replace more warning() calls with warningWithStack()
* Fixes after rebase + use warningWithStack in react
* Make warning have stack by default; warningWithoutStack opts out
* Forbid builds that may not use internals
* Revert newly added stacks
I changed my mind and want to keep this PR without functional changes. So we won't "fix" any warnings that are already missing stacks. We'll do it in follow-ups instead.
* Fix silly find/replace mistake
* Reorder imports
* Add protection against warning argument count mismatches
* Address review
While writing tests for unsafe async warnings, I noticed that in certain cases, errors were swallowed by the toWarnDev matcher and resulted in confusing test failures. For example, if an error prevented the code being tested from logging an expected warning- the test would fail saying that the warning hadn't been logged rather than reporting the unexpected error. I think a better approach for this is to always treat caught errors as the highest-priority reason for failing a test.
I reran all of the test cases for this matcher that I originally ran with PR #11786 and ensured they all still pass.
* Warn about spying on the console
* Added suppress warning flag for spyOn(console)
* Nits
* Removed spy-on-console guard
* Fixed a potential source of false-positives in toWarnDev() matcher
Also updated (most of) ReactIncrementalErrorLogging-test.internal to use the new matcher
* Removed unused third param to spyOn
* Improved clarity of inline comments
* Removed unused normalizeCodeLocInfo() method
* Added toWarnInDev matcher and connected to 1 test
* Added .toLowPriorityWarnDev() matcher
* Reply Jest spy with custom spy. Unregister spy after toWarnDev() so unexpected console.error/warn calls will fail tests.
* console warn/error throws immediately in tests by default (if not spied on)
* Pass-thru console message before erroring to make it easier to identify
* More robustly handle unexpected warnings within try/catch
* Error message includes remaining expected warnings in addition to unexpected warning
chun shangandDan Abramov
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