JavaScript codecoverage tool for Grunt
npm install grunt-istanbulnpm install grunt-istanbul
Gruntfile.js gruntfile:
javascript
grunt.loadNpmTasks('grunt-istanbul');
`
[grunt]: https://github.com/cowboy/grunt
[getting_started]: https://github.com/cowboy/grunt/blob/master/docs/getting_started.md
Documentation
To use this grunt-istanbul plugin, register a grunt task to run the following:
1. Instrument your source code
2. Run your test suite against your instrumented source code
3. Store your coverage results
4. Make the report
For step 2, an environment variable can be used to determine which path to use for loading
the source code to run the tests against. For example, when you normally run your tests you
want them to point directly at your source code. But when you run your instanbul code coverage
task you want your tests to point at your instrumented source code. The grunt-env plugin
can be used for setting an environment variable in a grunt task. Here's an example solution
that solves this problem using grunt-env and grunt-mocha-test:
`javascript
// in Gruntfile.js
module.exports = function (grunt) {
grunt.initConfig({
env: {
coverage: {
APP_DIR_FOR_CODE_COVERAGE: '../test/coverage/instrument/app/'
}
},
instrument: {
files: 'app/*.js',
options: {
lazy: true,
basePath: 'test/coverage/instrument/'
}
},
mochaTest: {
options: {
reporter: 'spec'
},
src: ['test/*.js']
},
storeCoverage: {
options: {
dir: 'test/coverage/reports'
}
},
makeReport: {
src: 'test/coverage/reports/*/.json',
options: {
type: 'lcov',
dir: 'test/coverage/reports',
print: 'detail'
}
}
});
grunt.registerTask('coverage', ['env:coverage', 'instrument', 'mochaTest',
'storeCoverage', 'makeReport']);
};
`
`javascript
// require_helper.js
module.exports = function (path) {
return require((process.env.APP_DIR_FOR_CODE_COVERAGE || '../app/') + path);
};
`
`javascript
// using requireHelper in a test
var requireHelper = require('../require_helper');
var formValidator = requireHelper('form_validator');
`
You can also pass an instrumenter argument to the instrument options as well as any other arguments that your instrumenter takes.
`javascript
// in Gruntfile.js
module.exports = function (grunt) {
var isparta = require('isparta');
grunt.initConfig({
instrument: {
files: 'app/*.es6',
options: {
lazy: true,
basePath: 'test/coverage/instrument/'
babel: {ignore: false, experimental: true, extensions: ['.es6']},
instrumenter: isparta.Instrumenter
}
}
});
};
`
If you want to specify a current working directory, you can specify a path the cwd options :
`javascript
// in Gruntfile.js
module.exports = function (grunt) {
var isparta = require('isparta');
grunt.initConfig({
instrument: {
files: '*/.es6',
options: {
cwd: 'app/'
lazy: true,
basePath: 'test/coverage/instrument/'
babel: {ignore: false, experimental: true, extensions: ['.es6']}
}
}
});
};
`
If you wan to insturment multiple locations, you specify multiple task targets:
`javascript
// in Gruntfile.js
module.exports = function (grunt) {
grunt.initConfig({
env: {
coverage: {
APP_DIR_FOR_CODE_COVERAGE: '../test/coverage/instrument/app/'
}
},
instrument: {
api: {
files: 'app/*.js',
options: {
basePath: 'test/coverage/instrument/'
}
},
web: {
files: 'web/*.js',
options: {
basePath: 'test/coverage/instrument/'
}
}
},
mochaTest: {
options: {
reporter: 'spec'
},
src: ['test/*.js']
},
storeCoverage: {
options: {
dir: 'test/coverage/reports'
}
},
makeReport: {
src: 'test/coverage/reports/*/.json',
options: {
type: 'lcov',
dir: 'test/coverage/reports',
print: 'detail'
}
}
});
grunt.registerTask('coverage', function(arg) {
var insturment = arg ? 'insturment:' + arg : 'insturment';
grunt.task.run(['env:coverage', instrument, 'mochaTest',
'storeCoverage', 'makeReport']);
});
`
`bash
coverage with api and web insturmentation
$ grunt coverage
coverage with api insturmentation
$ grunt coverage:api
coverage with web insturmentation
$ grunt coverage:web
`
By default only files that have coverage are stored. When the 'include-all-sources' option is set to true it will show all instrumented files even if their coverage percentage is 0. To see all instrumented files you can init the storeCoverage task as follows:
`javascript
grunt.initConfig({
storeCoverage: {
options: {
dir: 'test/coverage/reports',
'include-all-sources': true
}
}
});
`
Also, checkout the example Gruntfile.js in this repo (note that you do not need to implement the
reloadTasks` task in this example):