ember-cli-code-coverage

Code coverage using Istanbul for Ember apps.

Requirements

• If using Mocha, Testem >= 1.6.0 for which you need ember-cli > 2.4.3
• If using Mirage you need ember-cli-mirage >= 0.1.13
• If using Pretender (even as a dependency of Mirage) you need pretender >= 0.11.0
• If using Mirage or Pretender, you need to set up a passthrough for coverage to be written.
• ember-cli-babel >= 6.0.0

Installation

• ember install ember-cli-code-coverage

Usage

Coverage will only be generated when an environment variable is true (by default COVERAGE) and running your test command like normal.

For example:

COVERAGE=true ember test

If you want your coverage to work on both Unix and Windows, you can do this:

npm install cross-env --save-dev

and then:

cross-env COVERAGE=true ember test

Coverage also works when running tests in parallel, eg:

COVERAGE=true ember exam --split=2 --parallel=true

Configuration

Configuration is optional. It should be put in a file at config/coverage.js (configPath configuration in package.json is honored). In addition to this you can configure Istanbul by adding a .istanbul.yml file to the root directory of your app (See https://github.com/gotwarlost/istanbul#configuring)

Options

• coverageEnvVar: Defaults to COVERAGE. This is the environment variable that when set will cause coverage metrics to be generated.

• reporters: Defaults to ['lcov', 'html']. The json-summary reporter will be added to anything set here, it is required. This can be any reporters supported by Istanbul.

• excludes: Defaults to ['*/mirage/**/*']. An array of globs to exclude from instrumentation. Useful to exclude files from coverage statistics.

• coverageFolder: Defaults to coverage. A folder relative to the root of your project to store coverage results.

Example

  module.exports = {
    coverageEnvVar: 'COV'
  }

Create a passthrough when intercepting all ajax requests in tests

To work, this addon has to post coverage results back to a middleware at /write-coverage.

If you are using ember-cli-mirage you should add the following:

// in mirage/config.js

  this.passthrough('/write-coverage');
  this.namespace = 'api';  // It's important that the passthrough for coverage is before the namespace, otherwise it will be prefixed.

If you are using ember-cli-pretender you should add the following:

// where ever you set up the Pretender Server

  var server = new Pretender(function () {
    this.post('/write-coverage', this.passthrough);
  });

Testing code coverage goals

You can also test for code coverage goals with the included command ember test-code-coverage.

It takes the following parameters:

• target-lines: The target percentage for lines covered
• target-functions: The target percentage for functions covered
• target-statements: The target percentage for statements covered
• target-branches: The target percentage for branches covered

For example: ember test-code-coverage -target-lines=80 -target-branches=85

You can also configure those in the config/coverage.js file, in their camel cased form, like this:

 module.exports = {
    targetLines: 80,
    targetFunctions: 85.5,
  
    // Other configuration
    coverageEnvVar: 'COV'
  }

These values will then be the defaults when running ember test-code-coverage.

Running the command will output something like this to your console:

+ Lines covered:       60.00%   69.17%
+ Functions covered:   --.--%   72.18%
+ Statements covered:  --.--%   68.93%
- Branches covered:    70.00%   60.16%
- Test coverage check failed

For any type of check where no target is specified, it will simply output the actual value without doing any comparison.

Inspiration

This addon was inspired by ember-cli-blanket. The primary differences are that this addon uses Istanbul rather than Blanket for coverage and it instruments your application code as part of the build, when enabled.