grunt2gulp

Download it on NPM: npm install grunt2gulp

Converts a Gruntfile.js to a gulp-compliant file. Why? Because if you're going to create a new tool to replace an old one, why not automate the process of porting configuration files over.

In the future, a standard for building JavaScript files should emerge and be usable by whatever build tools exist. Maybe something like GNU Make? Ah, but that's a mere fantasy...

Installation

It's strongly preferable to install grunt2gulp using the Github repo rather than from the central NPM:

npm install https://github.com/omouse/grunt2gulp.js/archive/0.0.2-cool-card.tar.gz

Usage

Print out a gulp file to standard output:

grunt2gulp.js Gruntfile.js

Save the generated gulp file:

grunt2gulp.js Gruntfile.js > gulpfile.js

Drawbacks, Caveats

This is a very very rough tool, you will need to go over the generated gulp file to ensure that it works and is correct.

To see the difference, run the examples/simple-gruntfile.js through grunt2gulp and compare it to examples/simple-gulpfile.js. It got 90% of the way to a complete conversion though and it took only a bit of tweaking to get it to that state.

If there are duplicate tasks, a warning is added to the code.

How does it work?

It loads up the Gruntfile and emulates Grunt's API. When it's done looping through all the tasks in the grunt config, it shoves them into definitions or tasks. Definitions are non-objects, like strings, which need to be declared as variables when using Gulp. Tasks are converted into Gulp tasks but some special cases have to be handled, such as Karma and Watch.

Hacking on grunt2gulp

The code is dirty because Grunt is very permissive in its input. You can specify files in multiple ways: as a string, as a list of strings, or within a files property as a string or list. If Grunt were more modular it would be possible to just rip out the parser that Grunt uses to turn a config into a set of tasks without also importing the task running capability and all the other stuff.

The core functions you will want to check out are processGruntTask and processGruntConfig.

Using Docker for Testing

Build the image:

docker build -t omouse/grunt2gulp.js .

Run a container with the Gruntfile to test:

mkdir cool
touch cool/Gruntfile.js
docker run --rm -v $(realpath .):/data/package omouse/grunt2gulp.js

This will mount the cool directory to /data/package into the container. The container will run the grunt2gulp command using Gruntfile.js as input and output gulpfile.js into the cool directory.

The --rm will delete the container after it's done running.

To use docker for testing grunt2gulp on different files you can use npm test.

This requires that Docker is installed and that you have built the image. It also requires GNU Coreutils and realpath command. On Mac OS X you can use brew install coreutils.

Adding new gruntfile examples

1. Create a new directory in the examples/ directory
2. Create the Gruntfile.js in that new directory
3. Add a new line to docker-test-examples.sh

How to Report Issues

When reporting an issue with grunt2gulp.js, please try to include the Gruntfile that you were trying to convert and the error message that you received.

You can report issues here: https://github.com/omouse/grunt2gulp.js/issues

Documentation

You can generate the documentation using jsdoc:

jsdoc node_modules/grunt2gulp/bin/grunt2gulp.js

License

Licensed under the GPL version 3 or later.

Copyright (C) 2014-2016 Rudolf Olah [email protected]

See LICENSE for full text of license.

Known Issues With Gruntfiles

The following is a list of issues that you will have to correct yourself before trying to convert a Gruntfile. These are issues that are found by the linter (lintGruntFile).

Most of these issues can be fixed simply by removing or commenting out the offending line in the Gruntfile but will typically require extra work to be done to work as a gulpfile.

time-grunt or grunt-timer

It is useful to know how long a task runs for. With Grunt you would use time-grunt or the grunt-timer package. In gulp, you can use the gulp-duration and/or the time-require packages.

grunt.loadTasks or grunt.task.loadTasks

LoadTasks will load custom-defined tasks for Grunt. You will have to convert those tasks to work with gulp. The guide on writing a plugin for gulp is a good starting point.