Rake Default Task and Namespaces

Question

I have read through the docs and looked at quite a few examples but I am not clear on defaults and namespaces. (using rake, version 10.0.3)

First it seems, though I do not recall seeing this explicitly, that there can be only ONE default task regardless of how many are defined. Apparently the load order (PROJECT_NAME::Application.load_tasks) determines the winner. When I have struggled to create a namespaced default I have found that I have sometimes overridden the normal default for a rails app where:

rake

defaults to running the tests.

First here is the "rake -T" command:

$ rake -T a_name
rake a_name:a_task_1         # a_task_1
rake a_name:a_task_2         # a_task_2
rake a_name:b_name:b_task_1  # b_task_1
rake a_name:b_name:b_task_2  # b_task_2
rake a_name:default          # This is hopefully a namespaced default

When I run the namespace only which I am hoping is the "default" I get:

$ rake a_name
rake aborted!
Don't know how to build task 'a_name'

(See full trace by running task with --trace)

I was expecting this to run the b_task_1 in the b_name namespace because I have declared it as the default

However, If I explicitly tack on the word "default" I get this:

$  rake a_name:default
a_task_1

Anyway I am thoroughly confused. Can anyone help clarify this for me...

namespace :a_name do

  desc "a_task_1"
  task :a_task_1 do
    puts "a_task_1"
  end

  desc "a_task_2"
  task :a_task_2 do
    puts "a_task_2"
  end

  namespace :b_name do

    desc "b_task_1"
    task :b_task_1 do
      puts "b_task_1"
    end

    desc "b_task_2"
      task :b_task_2 do
    puts "b_task_2"
    end

  end

  desc "This is hopefully a namespaced default"
  task :default => 'b_name:b_task_1'
end

Answer 1

You can define a task with the same name as your namespace. It is not as pretty as having the default task defined inside the namespace itself I think.

desc "runs bar & baz in foo"
task foo: ["foo:bar", "foo:baz"]

namespace :foo do
  desc "bar in foo"
  task :bar do
    puts "bar"
  end

  desc "baz in foo"
  task :baz do
    puts "baz"
  end
end

And that's how they get listed:

rake foo                               # runs bar & baz in foo
rake foo:bar                           # bar in foo
rake foo:baz                           # baz in foo