26 lines
		
	
	
		
			793 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
		
		
			
		
	
	
			26 lines
		
	
	
		
			793 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
|  | # babel-jest
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|  | 
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|  | [Babel](https://github.com/babel/babel) [jest](https://github.com/facebook/jest) plugin | ||
|  | 
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|  | ## Usage
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|  | 
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|  | If you are already using `jest-cli`, just add `babel-jest` and it will automatically compile JavaScript code using Babel. | ||
|  | 
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|  | ```bash | ||
|  | yarn add --dev babel-jest @babel/core | ||
|  | ``` | ||
|  | 
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|  | If you would like to write your own preprocessor, uninstall and delete babel-jest and set the [config.transform](https://jestjs.io/docs/configuration#transform-object-string-string) option to your preprocessor. | ||
|  | 
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|  | ## Setup
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|  | 
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|  | _Note: this step is only required if you are using `babel-jest` with additional code preprocessors._ | ||
|  | 
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|  | To explicitly define `babel-jest` as a transformer for your JavaScript code, map _.js_ files to the `babel-jest` module. | ||
|  | 
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|  | ```json | ||
|  | "transform": { | ||
|  |   "^.+\\.jsx?$": "babel-jest" | ||
|  | }, | ||
|  | ``` |