Mergit

Mergit is a way to merge a bunch of required files into one file.

This allows you develop, design, and test your ruby script using normal ruby best practices (rspec, etc.) and then distribute them as a single-file ruby script.

Some use cases include:

• Administration scripts
• Simple tools
• Programs that need to work on any ruby without installing gems

When I wrote the original mergit, my goal was to distribute development/build scripts to a variety of systems.

These scripts had the following requirements:

1. The scripts needed to be easy to install.
   • Our developers hadn't had experience with Ruby yet. This is before ruby 1.9.2 was released!
   • We didn't have an in-house RPM server (which wouldn't help our Windows systems anyway).
2. The scripts needed minimal or no requirements.
   • Bundler and RVM were new and a pain to automatically install.
   • Not all systems had the (easy) root access needed to install required gems or build tools.
   • All the CentOS systems had Ruby (>= 1.8.7 by default)
   • All the Windows systems could easily get a version of Ruby (a quirk of our development/build environment).
   • We had a mechanism to get a reasonably current ruby for Solaris.
3. The scripts needed to work on Windows, Solaris, and CentOS.
4. I wanted to write the scripts with the best practices; unit tests, one-class-per-file, SOLID design.
   • I needed the scripts to work reliably, so I needed good tests.
   • It was easier to work on if we followed SOLID design principles.

The scripts I wrote in the end could be installed on any development or build system via a simple curl and only required any working ruby of version 1.8.7 or greater.

This was possible because all the .rb files were merged into single files, including the one gem I needed (the pure ruby minitar).

Mergit uses simple text processing, therefore it can be tripped up. Some known problems include:

• require statements nested in code instead of at outermost scope of a file will expand in-place. This probably isn't what you want.
• The order required files are pulled in may be different than ruby.
• The replacement feature is very brute force. Be careful using it.

Add this line to your application's Gemfile:

gem 'mergit', '~> 1.1'

And then execute:

$ bundle

Or install it yourself as:

$ gem install mergit

Note: Mergit uses Semantic Versioning.

The command line tool, mergit, is pretty self-explanatory.

You specify the ruby file you want requires merged into on the command line (via standard in, if you specify -) and any library directories you want required from.

You can specify the --lib flag multiple times.

There is also a --replace flag that lets you specify a string or regular expression (a string surrounded by /) that should be replaced.

Example:

bin/mergit --replace mouse=cat filename

This will replace all occurances of "mouse" with "cat".

You can specify the --replace flag multiple times.

Use the --output flag to send the resulting output to someplace other than stdout.

You can also cause any line to be skipped by adding a Mergit directive in a comment at the end of the line.

Example:

raise "This won't be in the merged output." # MERGIT: skip

Simple usage:

search_path = [ '/path/to/lib', '/path/to/other/lib' ]
mergit = Mergit.new(:search_path => search_path)

string_of_merged_file = mergit.process_file('/path/to/file')
# or
string_of_merged_string = mergit.process(some_string)

For more detailed information, see the documentation.

To use up less space, you can compress the resulting script with gzexe.

File an issue.

Make sure it includes the steps needed to reproduce it as well as what you expected to happen.

1. Fork it
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create new Pull Request

Repeat Level 2 until I give you write access on github. :-)