Web-Component-Tester-Istanbul

Istanbul coverage plugin for web-component-tester.

Use this plugin to collect and report test coverage (via istanbul) for your project on each test run.

Installation

npm install web-component-tester-istanbul --saveDev

Basic Usage

Add the following configuration to web-component-tester's config file.

Example

module.exports = {
  plugins: {
    istanbul: {
      dir: "./coverage",
      reporters: ["text-summary", "lcov"],
      include: [
        "**/*.js"
      ],
      exclude: [
        "/polymer/polymer.js",
        "/platform/platform.js"
      ]
    }
  }
}

Options

Below are the available configuration options:

dir

The directory to write coverage reports to.

reporters

An array of istanbul reporters to use.

include

Files to include in instrumentation.

exclude

Files to exclude from instrumentation (this trumps files 'included' with the option above).

Coverage Thresholds

In addition to measuring coverage, this plugin can be used to enforce coverage thresholds. If coverage does not meet the configured thresholds, then the test run will fail, even if all tests passed.

This requires specifying the thresholds option for the plugin

Example

The following configuration will cause the test run to fail if less than 100% of the statements in instrumented files are covered by tests.

module.exports = {
  plugins: {
    istanbul: {
      dir: "./coverage",
      reporters: ["text-summary", "lcov"],
      include: [
        "**/*.js"
      ],
      exclude: [
        "/polymer/polymer.js",
        "/platform/platform.js"
      ],
      thresholds: {
        global: {
          statements: 100
        }
      }
    }
  }
}