https://github.com/webpack-contrib/istanbul-instrumenter-loader
Istanbul Instrumenter Loader
https://github.com/webpack-contrib/istanbul-instrumenter-loader
coverage istanbul karma webpack-loader
Last synced: 5 months ago
JSON representation
Istanbul Instrumenter Loader
- Host: GitHub
- URL: https://github.com/webpack-contrib/istanbul-instrumenter-loader
- Owner: webpack-contrib
- License: mit
- Archived: true
- Created: 2014-09-25T02:48:17.000Z (over 11 years ago)
- Default Branch: master
- Last Pushed: 2020-12-10T17:11:12.000Z (over 5 years ago)
- Last Synced: 2025-12-21T07:56:20.339Z (5 months ago)
- Topics: coverage, istanbul, karma, webpack-loader
- Language: JavaScript
- Homepage:
- Size: 1.04 MB
- Stars: 270
- Watchers: 14
- Forks: 63
- Open Issues: 27
-
Metadata Files:
- Readme: README.md
- Changelog: CHANGELOG.md
- License: LICENSE
Awesome Lists containing this project
README
[![npm][npm]][npm-url]
[![node][node]][node-url]
[![deps][deps]][deps-url]
[![tests][tests]][tests-url]
[![coverage][cover]][cover-url]
[![chat][chat]][chat-url]
Istanbul Instrumenter Loader
Instrument JS files with [istanbul-lib-instrument](https://github.com/istanbuljs/istanbuljs/tree/master/packages/istanbul-lib-instrument) for subsequent code coverage reporting
Install
```bash
npm i -D istanbul-instrumenter-loader
```
Usage
### `References`
* [karma-webpack](https://github.com/webpack/karma-webpack)
* [karma-coverage-istanbul-reporter](https://github.com/mattlewis92/karma-coverage-istanbul-reporter)
### `Structure`
```
├─ src
│ |– components
│ | |– bar
│ | │ |─ index.js
│ | |– foo/
│ |– index.js
|– test
| |– src
| | |– components
| | | |– foo
| | | | |– index.js
```
To create a code coverage report for all components (even for those for which you have no tests yet) you have to require all the 1) sources and 2) tests. Something like it's described in ["alternative usage" of karma-webpack](https://github.com/webpack/karma-webpack#alternative-usage)
**test/index.js**
```js
// requires all tests in `project/test/src/components/**/index.js`
const tests = require.context('./src/components/', true, /index\.js$/);
tests.keys().forEach(tests);
// requires all components in `project/src/components/**/index.js`
const components = require.context('../src/components/', true, /index\.js$/);
components.keys().forEach(components);
```
> ℹ️ This file will be the only `entry` point for `karma`
**karma.conf.js**
```js
config.set({
...
files: [
'test/index.js'
],
preprocessors: {
'test/index.js': 'webpack'
},
webpack: {
...
module: {
rules: [
// instrument only testing sources with Istanbul
{
test: /\.js$/,
use: { loader: 'istanbul-instrumenter-loader' },
include: path.resolve('src/components/')
}
]
}
...
},
reporters: [ 'progress', 'coverage-istanbul' ],
coverageIstanbulReporter: {
reports: [ 'text-summary' ],
fixWebpackSourcePaths: true
}
...
});
```
### with `Babel`
You must run the instrumentation as a post step
**webpack.config.js**
```js
{
test: /\.js$|\.jsx$/,
use: {
loader: 'istanbul-instrumenter-loader',
options: { esModules: true }
},
enforce: 'post',
exclude: /node_modules|\.spec\.js$/,
}
```
Options
The loader supports all options supported by `istanbul-lib-instrument`
|Name|Type|Default|Description|
|:--:|:--:|:-----:|:----------|
|**`debug`**|`{Boolean}`|`false`|Turn on debugging mode|
|**`compact`**|`{Boolean}`|`true`|Generate compact code|
|**`autoWrap`**|`{Boolean}`|`false`|Set to `true` to allow return statements outside of functions|
|**`esModules`**|`{Boolean}`|`false`|Set to `true` to instrument ES2015 Modules|
|**`coverageVariable`**|`{String}`|`__coverage__`|Name of global coverage variable|
|**`preserveComments`**|`{Boolean}`|`false`|Preserve comments in `output`|
|**`produceSourceMap`**|`{Boolean}`|`false`|Set to `true` to produce a source map for the instrumented code|
|**`sourceMapUrlCallback`**|`{Function}`|`null`|A callback function that is called when a source map URL is found in the original code. This function is called with the source filename and the source map URL|
**webpack.config.js**
```js
{
test: /\.js$/,
use: {
loader: 'istanbul-instrumenter-loader',
options: {...options}
}
}
```
Maintainers
Kir Belevich
Juho Vepsäläinen
Joshua Wiens
Michael Ciniawsky
Matt Lewis
[npm]: https://img.shields.io/npm/v/istanbul-instrumenter-loader.svg
[npm-url]: https://npmjs.com/package/istanbul-instrumenter-loader
[node]: https://img.shields.io/node/v/istanbul-instrumenter-loader.svg
[node-url]: https://nodejs.org
[deps]: https://david-dm.org/webpack-contrib/istanbul-instrumenter-loader.svg
[deps-url]: https://david-dm.org/webpack-contrib/istanbul-instrumenter-loader
[tests]: http://img.shields.io/travis/webpack-contrib/istanbul-instrumenter-loader.svg
[tests-url]: https://travis-ci.org/webpack-contrib/istanbul-instrumenter-loader
[cover]: https://codecov.io/gh/webpack-contrib/istanbul-instrumenter-loader/branch/master/graph/badge.svg
[cover-url]: https://codecov.io/gh/webpack-contrib/istanbul-instrumenter-loader
[chat]: https://badges.gitter.im/webpack/webpack.svg
[chat-url]: https://gitter.im/webpack/webpack