grunt-image-check

Verify that your images are correctly resized for different resolutions

Getting Started

This plugin requires Grunt ~0.4.0

If you haven't used Grunt before, be sure to check out the Getting Started guide, as it explains how to create a Gruntfile as well as install and use Grunt plugins. Once you're familiar with that process, you may install this plugin with this command:

npm install grunt-image-check --save-dev

Once the plugin has been installed, it may be enabled inside your Gruntfile with this line of JavaScript:

grunt.loadNpmTasks('grunt-image-check');

The "image_check" task

Overview

In your project's Gruntfile, add a section named image_check to the data object passed into grunt.initConfig().

grunt.initConfig({
  image_check: {
    your_target: {
      // Target-specific options
    },
  },
});

Options

options.baseline

Type: String

Path to a folder where the images that are going to be used as baseline live

optsion.match

Type: String

A minimatch pattern that will be used to chose the files we actually want to compare. All files not matching the pattern will be ignored

options.compare

Type: Array

Array of objects representing the folders you want to compare against. The format of the object is:

{
  path: 'Path to the folder where the resized images live',
  proportion: 'Proportion you expect images in the given path to have compared to the baseline. If it is 2, then you expect images to be twice as large.'
}

Usage Examples

Check for images double the size

grunt.initConfig({
  image_check: {
    retina: {
      baseline: 'images/1x/',
      compare: [
        {
          path: 'images/2x/',
          proportion: 2
        }
      ]
    }
  },
});

Development

Tests

To run all the tests use this command:

grunt test

Integration tests

We have a few integration tests where we expect the task to fail. For these scenarios we use a special flag: negateOutput to return true when the task fails and false when the task passes.

Unit tests

We use mocha for our unit tests. You can find them under tests/unit/