context-require/README.md

Allows you to require files in a custom vm context.

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  context-require
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</h1>

Creates a new require function which runs all required modules in a context other than `global`.
Supports custom `require extensions` and `resolvers`. Useful for things like mocking the `package.json`
browser field without a bundler and using JSDOM (without using jsdom global) along side the native
commonjs require system.

Although other uses are possible this module was built to run tests in a browser like context
with out using a bundler. Because modules are cached once per context this tool also makes it easy to
isolate globals and state between tests running in the same process.

# Installation

```console
npm install context-require
```

# Example

**./index.js**
```javascript
import createRequire from "context-require";

const browserRequire = createRequire({
  dir: __dirname,
  context: new JSDOM('<div>Hello World</div>').window, // This object becomes the context for any required files.
  extensions: ..., // Same as require.extensions but only used in the above context.
  resolve(from, request, parentModule) {...} // Override file resolution for this context.
});

browserRequire("./get-document-body").innerHTML; // <div>Hello World</div>
```

**./get-document-body.js**
```js
typeof global; // undefined
module.exports = document.body;
```

### Contributions

* Use `npm test` to build and run tests.

Please feel free to create a PR!