module Rake::DSL

Describes the next rake task. Duplicate descriptions are discarded. Descriptions are shown with rake -T (up to the first sentence) and rake -D (the entire description).

Example:

desc "Run the Unit Tests"
task test: [:build]
  # ... run tests
end

# File lib/rake/dsl_definition.rb, line 171
def desc(description) # :doc:
  Rake.application.last_description = description
end

Declare a set of files tasks to create the given directories on demand.

Example:

directory "testdata/doc"

# File lib/rake/dsl_definition.rb, line 98
def directory(*args, &block) # :doc:
  result = file_create(*args, &block)
  dir, _ = *Rake.application.resolve_args(args)
  dir = Rake.from_pathname(dir)
  Rake.each_dir_parent(dir) do |d|
    file_create d do |t|
      mkdir_p t.name unless File.exist?(t.name)
    end
  end
  result
end

Declare a file task.

Example:

 file "config.cfg" => ["config.template"] do
   open("config.cfg", "w") do |outfile|
     open("config.template") do |infile|
       while line = infile.gets
         outfile.puts line
       end
     end
   end
end

# File lib/rake/dsl_definition.rb, line 82
def file(*args, &block) # :doc:
  Rake::FileTask.define_task(*args, &block)
end

Import the partial Rakefiles fn. Imported files are loaded after the current file is completely loaded. This allows the import statement to appear anywhere in the importing file, and yet allowing the imported files to depend on objects defined in the importing file.

A common use of the import statement is to include files containing dependency declarations.

See also the –rakelibdir command line option.

Example:

import ".depend", "my_rules"

# File lib/rake/dsl_definition.rb, line 189
def import(*fns) # :doc:
  fns.each do |fn|
    Rake.application.add_import(fn)
  end
end

Declare a task that performs its prerequisites in parallel. Multitasks does not guarantee that its prerequisites will execute in any given order (which is obvious when you think about it)

Example:

multitask deploy: %w[deploy_gem deploy_rdoc]

# File lib/rake/dsl_definition.rb, line 118
def multitask(*args, &block) # :doc:
  Rake::MultiTask.define_task(*args, &block)
end

Create a new rake namespace and use it for evaluating the given block. Returns a NameSpace object that can be used to lookup tasks defined in the namespace.

Example:

ns = namespace "nested" do
  # the "nested:run" task
  task :run
end
task_run = ns[:run] # find :run in the given namespace.

Tasks can also be defined in a namespace by using a “:” in the task name:

task "nested:test" do
  # ...
end

# File lib/rake/dsl_definition.rb, line 141
def namespace(name=nil, &block) # :doc:
  name = name.to_s if name.kind_of?(Symbol)
  name = name.to_str if name.respond_to?(:to_str)
  unless name.kind_of?(String) || name.nil?
    raise ArgumentError, "Expected a String or Symbol for a namespace name"
  end
  Rake.application.in_namespace(name, &block)
end

Declare a rule for auto-tasks.

Example:

rule '.o' => '.c' do |t|
  sh 'cc', '-o', t.name, t.source
end

# File lib/rake/dsl_definition.rb, line 157
def rule(*args, &block) # :doc:
  Rake::Task.create_rule(*args, &block)
end

Declare a basic task. The task_name is always the first argument. If the task name contains a “:” it is defined in that namespace.

The dependencies may be a single task name or an Array of task names. The argument (a single name) or arguments (an Array of names) define the arguments provided to the task.

The task, argument and dependency names may be either symbols or strings.

A task with a single dependency:

task clobber: %w[clean] do
  rm_rf "html"
end

A task with an argument and a dependency:

task :package, [:version] => :test do |t, args|
  # ...
end

To invoke this task from the command line:

$ rake package[1.2.3]

Alternate definition:

task :package, :version, needs: :test do |t, args|
  # ...
end

# File lib/rake/dsl_definition.rb, line 65
def task(*args, &block) # :doc:
  Rake::Task.define_task(*args, &block)
end