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## Summary
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References Standardize file naming #4969.
Updates naming in package expect. Uses conventions listed in #4969 (comment):
- Files that primarily export types, objects or classes should use CapitalizedFileNames.js and should mirror what’s inside 1:1.
- Files that export a single function should have the function name with camelCase in it.
- Folder names should use dashes, unless they are special folders.
### Decisions
- Test & snapshot files retained their name, but converted it to camelCase.
- Files which exported an object were named according to the internal object, which was camelCase. However, I believe that the standard referenced above states that objects should have CapitalizedNames. Should the internal objects be renamed too?
- `matchers.js`
- `jestMatchersObject.js`
- `spyMatchers.js`
- `toThrowmatchers.js`
### Questions
How should `asymmetricMatchers.js` be named? It exports a class `AsymmetricMatcher`, but it also exports a bunch of functions, and was named in camelCase before.
## Test plan
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Output of yarn run test on master and standardize filenames in packages/jest circus branches was the same.
[jest-test-expect-master.txt](https://github.com/facebook/jest/files/2532360/jest-test-expect-master.txt)
[jest-test-expect-standardize-filenames.txt](https://github.com/facebook/jest/files/2532363/jest-test-expect-standardize-filenames.txt)
* Add a fake chalk in order to work in older browsers
Closes#4074
* Make fake chalk private
* fix import
* Normalize ansi-styles version
* Remove yarn.lock from npmignore
* Move fake chalk into expect package
* Remove browser builds for sub dependencies
* Add karma browser tests for es5 builds
* Use rollup for browser builds
* Review comment + prettier
* Fix rollup build by using export for jest-matchers
* Run prettier on unrelated file
Simen Bekkhus