## Development Setup

This project uses a monorepo setup that requires using [Yarn](https://yarnpkg.com) because it relies on [Yarn workspaces](https://yarnpkg.com/blog/2017/08/02/introducing-workspaces/).

``` sh
# install dependencies
yarn

# link `vue` executable
# if you have the old vue-cli installed globally, you may
# need to uninstall it first.
cd packages/@vue/cli
yarn link

# create test projects in /packages/test
cd -
cd packages/test
vue create test-app
cd test-app
yarn serve
```

### Testing Tips

The full test suite is rather slow, because it has a number of e2e tests that perform full webpack builds of actual projects. To narrow down the tests needed to run during development, you can pass the test script a regex to match test filenames:

``` sh
yarn test <filenameRegex>
```

Note the regex matches against full paths relative to the project root, so for example if you want to test all the prompt modules in `packages/@vue/cli/lib/promptModules`, you can simply run:

``` sh
yarn test promptModules
```

Alternatively, you can run the tests inside specific packages with the `-p` flag:

``` sh
yarn test -p cli,cli-service
```

If the package is a plugin, you can omit the `cli-plugin-` prefix:

``` sh
yarn test -p typescript
```

You can also pass `--watch` to run tests in watch mode.

Note that `jest --onlyChanged` isn't always accurate because some tests spawn child processes.

### Plugin Development

See [dedicated section in docs](https://github.com/vuejs/vue-cli/blob/dev/docs/dev-guide/plugin-dev.md).
