react/packages/jest-react/README.md

# `jest-react`

Jest matchers and utilities for testing React Test Renderer.
Jest + test renderer helpers for concurrent mode (#13751) * 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 2018-10-04 08:37:41 +08:00			# `jest-react`

			`Jest matchers and utilities for testing React Test Renderer.`