rake 方法间调用

**rake方法间的调用**
==================================
namespace :test_rake do
? desc "fun 1"
? task :test_a => :environment do
??? puts "test_a"
? end

? desc "fun 2"
? task :test_b => :environment do
??? puts "test_b"
? end

? desc "fun 1 & 2"
? task :test_c => :environment do
??? Rake::Task["test_rake:test_a"].invoke
??? Rake::Task["test_rake:test_b"].invoke
? end
end