README.md
# grunt-flow-type-check
> Run Facebook's Flow static type checker
[](https://travis-ci.org/isuttell/grunt-flow-type-check)
[](https://codeclimate.com/github/isuttell/grunt-flow-type-check)
[](https://codeclimate.com/github/isuttell/grunt-flow-type-check)
[](https://www.npmjs.org/package/grunt-flow-type-check)
[](https://www.npmjs.org/package/grunt-flow-type-check)
## Getting Started
This plugin requires Grunt `>=0.4.0`
If you haven't used [Grunt](http://gruntjs.com/) before, be sure to check out the [Getting Started](http://gruntjs.com/getting-started) guide, as it explains how to create a [Gruntfile](http://gruntjs.com/sample-gruntfile) as well as install and use Grunt plugins. Once you're familiar with that process, you may install this plugin with this command:
```shell
npm install grunt-flow-type-check --save-dev
```
Once the plugin has been installed, it may be enabled inside your Gruntfile with this line of JavaScript:
```js
grunt.loadNpmTasks('grunt-flow-type-check');
```
## The "flow" task
_Run this task with the `grunt flow` command._
[Flow](http://flowtype.org) is a static type checker, designed to find type errors in JavaScript programs. Typed Flow code easily transforms down to regular JavaScript, so it runs anywhere.
### Overview
In your project's Gruntfile, add a section named `flow` to the data object passed into `grunt.initConfig()`.
```js
grunt.initConfig({
flow: {
app: {
src: 'src/', // `.flowconfig` folder
options: {
background: false, // Watch/Server mode
all: false, // Check all files regardless
lib: '', // Library directory
stripRoot: false, // Relative vs Absolute paths
weak: false, // Force weak check
showAllErrors: false, // Show more than 50 errors
}
}
}
});
```
### Options
#### src
Type: `String`
Default value: `.`
Default location of `.flowconfig`
#### options.weak
Type: `Boolean`
Default value: `false`
Use the weak option to check the files.
#### options.lib
Type: `String`
Default value: ``
Library folder. This can be defined here or in `flowconfig`.
#### options.showAllErrors
Type: `Boolean`
Default value: `false`
By default only the first 50 errors are shown. This will show all of them.
#### options.stripRoot
Type: `Boolean`
Default value: `false`
Use relative paths instead of absolute
#### options.all
Type: `Boolean`
Default value: `false`
Checks all files regardless of if they have `/* @flow */` at the top. Use this with care.
#### options.background
Type: `Boolean`
Default value: `false`
Run the Flow server in the background. This is used in conjunction with watch.
### Usage Examples
#### Basic
By default we check for `.flowconfig` in the root directory and then run `flow check`
```js
grunt.initConfig({
flow: {
app: {
src: '.',
options: {
background: false,
}
}
},
});
```
#### Watch
Running `flow check` each time can be slow. Alternatively, you can run the Flow server in the background and use [grunt-contrib-watch](https://github.com/gruntjs/grunt-contrib-watch) to get any current errors when a files changes.
```js
grunt.initConfig({
flow: {
watch: {
src: '.',
options: {
// Task-specific options go here.
background: true
}
}
},
watch : {
flow: {
files: ['src/**/*.jsx'],
tasks: ['flow:watch:status'] // Get the status from the server
}
}
});
// Run 'flow:watch:start' before the watch task to start the server
grunt.registerTask('watchFlow', ['flow:watch:start', 'watch']);
```
#### Single File
You can also run a single file at a time through `flow`, however this it not recommended for projects with multiple files and/or external dependencies.
```js
grunt.initConfig({
flow: {
app: {
options: {
showAllErrors: false, // This the only option avaiable in this mode
},
files: {
src: ['src/**/*.js'] // Will run flow individually on each .js file in the src/ directory
}
}
},
});
```
## Contributing
Please take care to maintain the existing coding style. Add unit tests for any new or changed functionality. Lint and test your code using 'grunt test'.
## Release History
* v0.4.4 - Switched to flow-bin
* v0.4.3 - Updated binaries and task to support flow 0.4.0
* v0.4.2 - Refactor and removed extraneous option
* v0.4.1 - Fixed bug where watch didn't work
* v0.4.0 - Added single file check, colors and Flow binaries to 0.1.2
* v0.3.0 - Added additional options
* v0.2.1 - Fixed path issue for Flow binaries
* v0.2.0 - Added watch support
* v0.1.0 - Initial Release