Rake 0.7.0 Released

These changes for Rake have been brewing for a long time. Here they are, I hope you enjoy them.

Changes

New Features

  • Name space support for task names (see below).
  • Prerequisites can be executed in parallel (see below).
  • Added safe_ln support for openAFS (via Ludvig Omholt).
  • RDoc defaults to internal (in-process) invocation. The old behavior is still available by setting the external flag to true.
  • Rakefiles are now loaded with the expanded path to prevent accidental polution from the Ruby load path.
  • Task objects my now be used in prerequisite lists directly.
  • Task objects (in addition to task names) may now be included in the prerequisite list of a task.
  • Internals cleanup and refactoring.

Bug Fixes

  • Compatibility fixes for Ruby 1.8.4 FileUtils changes.

Namespaces

Tasks can now be nested inside their own namespaces. Tasks within one namespace will not accidently interfer with tasks named in a different namespace.

For example:

  namespace "main" do
    task :build do
      # Build the main program
    end
  end

  namespace "samples" do
    task :build do
      # Build the sample programs
    end
  end

  task :build_all => ["main:build", "samples:build"]

Even though both tasks are named :build, they are separate tasks in their own namespaces. The :build_all task (defined in the toplevel namespace) references both build tasks in its prerequisites.

You may invoke each of the individual build tasks with the following commands:

  rake main:build
  rake samples:build

Or invoke both via the :build_all command:

  rake build_all

Namespaces may be nested arbitrarily. Since the name of file tasks correspond to the name of a file in the external file system, FileTasks are not affected by the namespaces.

See the Rakefile format documentation (in the Rake API documents) for more information.

Parallel Tasks

Sometimes you have several tasks that can be executed in parallel. By specifying these tasks as prerequisites to a multitask task.

In the following example the tasks copy_src, copy_doc and copy_bin will all execute in parallel in their own thread.

  multitask :copy_files => [:copy_src, :copy_doc, :copy_bin] do
    puts "All Copies Complete"
  end

What is Rake

Rake is a build tool similar to the make program in many ways. But instead of cryptic make recipes, Rake uses standard Ruby code to declare tasks and dependencies. You have the full power of a modern scripting language built right into your build tool.

Availability

The easiest way to get and install rake is via RubyGems …

  gem install rake    (you may need root/admin privileges)

Otherwise, you can get it from the more traditional places:

Home Page:rake.rubyforge.org/
Download:rubyforge.org/project/showfiles.php?group_id=50

Thanks

As usual, it was input from users that drove a alot of these changes. The following people either contributed patches, made suggestions or made otherwise helpful comments. Thanks to …

  • Doug Young (inspriation for the parallel task)
  • David Heinemeier Hansson (for —trace message enhancement and for pushing for namespace support).
  • Ludvig Omholt (for the openAFS fix)