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facebook / react-native

A framework for building native applications using React
https://reactnative.dev
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Fix lazy import error from jest and Appearance.js #47629

Open Kudo opened 2 days ago

Kudo commented 2 days ago

Summary:

currently running jest test, it shows an error:

ReferenceError: You are trying to `import` a file after the Jest environment has been torn down. From __tests__/App.test.tsx.

      at getState (node_modules/react-native/Libraries/Utilities/Appearance.js:18:26)
      at addChangeListener (node_modules/react-native/Libraries/Utilities/Appearance.js:71:19)
      at subscribe (node_modules/react-native/Libraries/Utilities/useColorScheme.js:10:66)
      at subscribeToStore (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:6232:10)
      at commitHookEffectListMount (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:13038:26)
      at commitPassiveMountOnFiber (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:14461:11)
      at commitPassiveMountEffects_complete (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:14421:9)
      at commitPassiveMountEffects_begin (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:14408:7)
      at commitPassiveMountEffects (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:14396:3)
      at flushPassiveEffectsImpl (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:16287:3)
      at flushPassiveEffects (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:16236:14)
      at node_modules/react-test-renderer/cjs/react-test-renderer.development.js:16051:9
      at workLoop (node_modules/scheduler/cjs/scheduler.development.js:266:34)
      at flushWork (node_modules/scheduler/cjs/scheduler.development.js:239:14)
      at Immediate.performWorkUntilDeadline [as _onImmediate] (node_modules/scheduler/cjs/scheduler.development.js:533:21)

it is a regression from #46123 that to have a lazy require.

this pr tries to mock useColorScheme to return light. i think we don't necessarily test the color scheme changes in jest runtime. originally useColorScheme also returns light because of this statement

Changelog:

[GENERAL] [FIXED] - Fixed jest error from Appearance.js

Test Plan:

$ npx @react-native-community/cli init RN0762 --pm bun --version 0.76.2
$ cd RN0762
$ bun test run
Kudo commented 1 day ago

we can either mock https://github.com/facebook/react-native/blob/9a60038a40e16925ea1adeb3e3c937c22a615485/packages/react-native/Libraries/Utilities/Appearance.js. but that feels more complex to mock getColorScheme(), setColorScheme(), addChangeListener() to correct behavior.