feat(StrictMode): Double-invoke render for every component

[eps1lon]

Summary

Closes #18426.

Essentially #14639 rebased with master where concerns were voiced about existing tests.

Test Plan

ReactHooks-internal is responsible for this test. This also affects any test counting renders.

[codesandbox-ci]

This pull request is automatically built and testable in CodeSandbox.

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Latest deployment of this branch, based on commit e508cee:

Sandbox	Source
autumn-surf-xpr5j	Configuration
StrictMode /w and w/o Hooks	Issue #18426

[sizebot]

Details of bundled changes.

Comparing: 1af2a10...e508cee

react-art

File	Filesize Diff	Gzip Diff	Prev Size	Current Size	Prev Gzip	Current Gzip	ENV
react-art.development.js	-0.1%	-0.0%	540.9 KB	540.57 KB	116.64 KB	116.59 KB	NODE_DEV
react-art.production.min.js	0.0%	-0.0%	71.47 KB	71.47 KB	21.57 KB	21.56 KB	NODE_PROD
ReactART-dev.js	-0.1%	-0.0%	607.38 KB	606.88 KB	127.32 KB	127.28 KB	FB_WWW_DEV
react-art.development.js	-0.1%	-0.0%	636.84 KB	636.49 KB	134.27 KB	134.24 KB	UMD_DEV
react-art.production.min.js	0.0%	0.0%	106.42 KB	106.42 KB	32.3 KB	32.3 KB	UMD_PROD

react-dom

File	Filesize Diff	Gzip Diff	Prev Size	Current Size	Prev Gzip	Current Gzip	ENV
react-dom.production.min.js	0.0%	-0.0%	118.55 KB	118.55 KB	37.26 KB	37.26 KB	NODE_PROD
react-dom-test-utils.development.js	0.0%	-0.0%	59.23 KB	59.23 KB	15.64 KB	15.64 KB	UMD_DEV
ReactDOMTesting-profiling.js	0.0%	-0.0%	406 KB	406 KB	73.77 KB	73.77 KB	FB_WWW_PROFILING
react-dom-server.browser.production.min.js	0.0%	-0.0%	19.62 KB	19.62 KB	7.29 KB	7.28 KB	NODE_PROD
react-dom-unstable-fizz.browser.development.js	0.0%	-0.2%	3.34 KB	3.34 KB	1.26 KB	1.26 KB	UMD_DEV
react-dom.profiling.min.js	0.0%	0.0%	122.4 KB	122.4 KB	38.41 KB	38.42 KB	NODE_PROFILING
react-dom-test-utils.production.min.js	0.0%	0.0%	12.25 KB	12.25 KB	4.54 KB	4.54 KB	UMD_PROD
react-dom-unstable-fizz.browser.production.min.js	0.0%	-0.3%	1.17 KB	1.17 KB	691 B	689 B	UMD_PROD
react-dom-server.node.development.js	0.0%	-0.0%	127.53 KB	127.53 KB	34.09 KB	34.09 KB	NODE_DEV
react-dom-server.node.production.min.js	0.0%	-0.0%	20.03 KB	20.03 KB	7.44 KB	7.44 KB	NODE_PROD
ReactDOMForked-dev.js	-0.0%	-0.0%	1008.64 KB	1008.15 KB	224.19 KB	224.14 KB	FB_WWW_DEV
react-dom-unstable-fizz.node.development.js	0.0%	-0.1%	3.68 KB	3.68 KB	1.33 KB	1.33 KB	NODE_DEV
react-dom.development.js	-0.0%	-0.0%	908.87 KB	908.53 KB	199.94 KB	199.91 KB	UMD_DEV
react-dom-server.browser.development.js	0.0%	-0.0%	133.15 KB	133.15 KB	34.27 KB	34.27 KB	UMD_DEV
react-dom-unstable-fizz.node.production.min.js	0.0%	-0.2%	1.15 KB	1.15 KB	653 B	652 B	NODE_PROD
react-dom-server.browser.production.min.js	0.0%	-0.0%	19.71 KB	19.71 KB	7.34 KB	7.34 KB	UMD_PROD
ReactDOMTesting-dev.js	0.0%	-0.0%	946.27 KB	946.27 KB	211.29 KB	211.29 KB	FB_WWW_DEV
react-dom.development.js	-0.0%	-0.0%	865.15 KB	864.82 KB	197.49 KB	197.47 KB	NODE_DEV
ReactDOMTesting-prod.js	0.0%	-0.0%	406 KB	406 KB	73.77 KB	73.77 KB	FB_WWW_PROD
ReactDOM-dev.js	-0.0%	-0.0%	1008.64 KB	1008.15 KB	224.19 KB	224.14 KB	FB_WWW_DEV
ReactDOMServer-dev.js	0.0%	-0.0%	136.32 KB	136.32 KB	34.74 KB	34.74 KB	FB_WWW_DEV
react-dom-test-utils.development.js	0.0%	-0.0%	54.69 KB	54.69 KB	15.03 KB	15.03 KB	NODE_DEV
ReactDOMServer-prod.js	0.0%	-0.0%	46.62 KB	46.62 KB	10.86 KB	10.86 KB	FB_WWW_PROD
react-dom-unstable-fizz.browser.development.js	0.0%	-0.2%	2.94 KB	2.94 KB	1.17 KB	1.17 KB	NODE_DEV
react-dom-test-utils.production.min.js	0.0%	-0.0%	12.1 KB	12.1 KB	4.47 KB	4.47 KB	NODE_PROD
react-dom-unstable-native-dependencies.development.js	0.0%	-0.0%	57.7 KB	57.7 KB	14.36 KB	14.36 KB	UMD_DEV
react-dom-unstable-fizz.browser.production.min.js	0.0%	-0.3%	1013 B	1013 B	603 B	601 B	NODE_PROD
react-dom-unstable-native-dependencies.production.min.js	0.0%	-0.0%	10.31 KB	10.31 KB	3.49 KB	3.49 KB	UMD_PROD
react-dom-unstable-native-dependencies.development.js	0.0%	-0.0%	54.71 KB	54.71 KB	14.14 KB	14.13 KB	NODE_DEV
react-dom-unstable-native-dependencies.production.min.js	0.0%	-0.0%	10.04 KB	10.04 KB	3.37 KB	3.37 KB	NODE_PROD

react-reconciler

File	Filesize Diff	Gzip Diff	Prev Size	Current Size	Prev Gzip	Current Gzip	ENV
react-reconciler.development.js	-0.1%	-0.0%	578.94 KB	578.61 KB	122.44 KB	122.42 KB	NODE_DEV
react-reconciler-reflection.development.js	0.0%	-0.0%	15.55 KB	15.55 KB	4.73 KB	4.73 KB	NODE_DEV
react-reconciler.production.min.js	0.0%	-0.0%	76.31 KB	76.31 KB	22.64 KB	22.64 KB	NODE_PROD
react-reconciler-reflection.production.min.js	0.0%	-0.1%	2.57 KB	2.57 KB	1.08 KB	1.08 KB	NODE_PROD

ReactDOM: size: 0.0%, gzip: 0.0%

Size changes (stable)

Generated by 🚫 dangerJS against e508cee

[sizebot]

Details of bundled changes.

Comparing: 1af2a10...e508cee

react-dom

File	Filesize Diff	Gzip Diff	Prev Size	Current Size	Prev Gzip	Current Gzip	ENV
react-dom-server.browser.production.min.js	0.0%	-0.0%	20.17 KB	20.17 KB	7.4 KB	7.4 KB	UMD_PROD
react-dom-unstable-fizz.browser.development.js	0.0%	-0.2%	3.35 KB	3.35 KB	1.27 KB	1.27 KB	UMD_DEV
ReactDOM-dev.js	-0.1%	-0.0%	962.79 KB	962.29 KB	214.16 KB	214.08 KB	FB_WWW_DEV
react-dom-unstable-fizz.browser.production.min.js	0.0%	-0.3%	1.19 KB	1.19 KB	699 B	697 B	UMD_PROD
ReactDOM-profiling.js	0.0%	-0.0%	416.74 KB	416.74 KB	75.49 KB	75.48 KB	FB_WWW_PROFILING
react-dom-unstable-fizz.browser.development.js	0.0%	-0.2%	2.95 KB	2.95 KB	1.18 KB	1.18 KB	NODE_DEV
react-dom-unstable-fizz.browser.production.min.js	0.0%	-0.3%	1 KB	1 KB	611 B	609 B	NODE_PROD
react-dom-test-utils.development.js	0.0%	-0.0%	59.24 KB	59.24 KB	15.65 KB	15.65 KB	UMD_DEV
ReactDOMTesting-dev.js	0.0%	-0.0%	919.51 KB	919.51 KB	205.39 KB	205.38 KB	FB_WWW_DEV
react-dom-test-utils.development.js	0.0%	-0.0%	54.7 KB	54.7 KB	15.03 KB	15.03 KB	NODE_DEV
react-dom-server.node.development.js	0.0%	-0.0%	129.05 KB	129.05 KB	34.3 KB	34.3 KB	NODE_DEV
react-dom-test-utils.production.min.js	0.0%	-0.0%	12.12 KB	12.12 KB	4.48 KB	4.48 KB	NODE_PROD
react-dom-server.browser.development.js	0.0%	-0.0%	127.83 KB	127.83 KB	34.05 KB	34.05 KB	NODE_DEV
react-dom.development.js	-0.0%	-0.0%	939.02 KB	938.56 KB	205.19 KB	205.16 KB	UMD_DEV
react-dom-unstable-native-dependencies.development.js	0.0%	-0.0%	57.71 KB	57.71 KB	14.36 KB	14.36 KB	UMD_DEV
ReactDOMForked-dev.js	-0.1%	-0.0%	962.79 KB	962.29 KB	214.16 KB	214.08 KB	FB_WWW_DEV
react-dom-unstable-native-dependencies.production.min.js	0.0%	-0.0%	10.32 KB	10.32 KB	3.49 KB	3.49 KB	UMD_PROD
ReactDOMServer-dev.js	0.0%	-0.0%	135.47 KB	135.47 KB	34.6 KB	34.6 KB	FB_WWW_DEV
ReactDOMServer-prod.js	0.0%	-0.0%	45.91 KB	45.91 KB	10.67 KB	10.67 KB	FB_WWW_PROD
react-dom.development.js	-0.0%	-0.0%	894.04 KB	893.6 KB	202.7 KB	202.67 KB	NODE_DEV
ReactDOMForked-profiling.js	0.0%	-0.0%	416.74 KB	416.74 KB	75.49 KB	75.48 KB	FB_WWW_PROFILING
react-dom-unstable-native-dependencies.development.js	0.0%	-0.0%	54.72 KB	54.72 KB	14.14 KB	14.14 KB	NODE_DEV
react-dom-unstable-fizz.node.development.js	0.0%	-0.1%	3.69 KB	3.69 KB	1.34 KB	1.34 KB	NODE_DEV
react-dom-unstable-native-dependencies.production.min.js	0.0%	-0.0%	10.05 KB	10.05 KB	3.38 KB	3.38 KB	NODE_PROD
react-dom-unstable-fizz.node.production.min.js	0.0%	-0.2%	1.16 KB	1.16 KB	662 B	661 B	NODE_PROD

react-art

File	Filesize Diff	Gzip Diff	Prev Size	Current Size	Prev Gzip	Current Gzip	ENV
ReactART-dev.js	-0.1%	-0.0%	579.3 KB	578.81 KB	121.65 KB	121.6 KB	FB_WWW_DEV
react-art.development.js	-0.1%	-0.0%	657.47 KB	657 KB	137.97 KB	137.95 KB	UMD_DEV
react-art.production.min.js	0.0%	-0.0%	109 KB	109 KB	33.06 KB	33.06 KB	UMD_PROD
react-art.development.js	-0.1%	-0.0%	560.72 KB	560.28 KB	120.36 KB	120.32 KB	NODE_DEV

react-native-renderer

File	Filesize Diff	Gzip Diff	Prev Size	Current Size	Prev Gzip	Current Gzip	ENV
ReactNativeRenderer-dev.js	-0.1%	-0.0%	657.7 KB	657.33 KB	142.08 KB	142.04 KB	RN_FB_DEV
ReactFabric-dev.js	0.0%	-0.0%	636.85 KB	636.85 KB	137.34 KB	137.34 KB	RN_OSS_DEV
ReactFabric-prod.js	0.0%	0.0%	260.81 KB	260.81 KB	45.16 KB	45.16 KB	RN_OSS_PROD
ReactFabric-profiling.js	0.0%	0.0%	272.65 KB	272.65 KB	47.39 KB	47.4 KB	RN_OSS_PROFILING
ReactFabric-dev.js	-0.1%	-0.0%	639.57 KB	639.2 KB	137.67 KB	137.62 KB	RN_FB_DEV
ReactNativeRenderer-prod.js	0.0%	-0.0%	268.82 KB	268.82 KB	46.64 KB	46.64 KB	RN_OSS_PROD
ReactNativeRenderer-profiling.js	0.0%	-0.0%	280.67 KB	280.67 KB	48.89 KB	48.89 KB	RN_OSS_PROFILING

react-reconciler

File	Filesize Diff	Gzip Diff	Prev Size	Current Size	Prev Gzip	Current Gzip	ENV
react-reconciler-reflection.development.js	0.0%	-0.0%	15.56 KB	15.56 KB	4.73 KB	4.73 KB	NODE_DEV
react-reconciler-reflection.production.min.js	0.0%	-0.1%	2.58 KB	2.58 KB	1.09 KB	1.09 KB	NODE_PROD
react-reconciler.development.js	-0.1%	-0.0%	601.08 KB	600.65 KB	126.67 KB	126.63 KB	NODE_DEV

ReactDOM: size: 0.0%, gzip: -0.0%

Size changes (experimental)

Generated by 🚫 dangerJS against e508cee

[gaearon]

Seems like bundle tests fail.

[eps1lon]

Seems like bundle tests fail.

It seems like react-test-renderer is not using beginWork from the react-reconciler package in test-build (but is in test).

Apparently test-build rewrites some react-reconciler/ imports but I'm a bit confused why react-reconciler sometimes imports via relative specifier (e.g. ./ReactFiberRoot) and sometimes via deep specifier (e.g. react-reconciler/src/ReactRootTags). Maybe I'm looking in the wrong spot.

[eps1lon]

Following https://github.com/facebook/react/pull/14639/files#diff-0b241de0dfec2d07bb2b2fef76b254d2R11-R24 though I don't think I understand the distinction between source and build tests.

[gaearon]

It seems like react-test-renderer is not using beginWork from the react-reconciler package in test-build (but is in test).

Not sure what you mean by this. In the bundle tests, react-reconciler is bundled inside of react-test-renderer bundle. Just like it's bundled inside of react-dom.

The difference is that you can't set feature flags for bundle tests. Because nothing will read them. They're already compiled away.

[gaearon]

Looks good. Thanks.