ruby - How to test rake task callbacks -

i create test code rspec. want test callback executed or not.
task main: [:callback] means run callback before main, doesn't it?

but test failed. looks callback not executed. why?

require 'rails_helper' require 'rake'  rspec.describe 'rake::task'   before(:all)     @rake = rake::application.new     rake.application = @rake     rake.application.rake_require('rspec_before', ["#{rails.root}/lib/tasks"])   end    subject { @rake['rspec_before:main'].execute }    "expects run callback before main task"     expect{ subject }.to output(/hello, world/).to_stdout   end end 

my rake task below.

namespace :rspec_before   task :callback     @greeting = "hello, world"   end    # case 1   # in case, `callback` not executed in rspec   # in console, `callback` executed !!!!   desc "main task"   task main: [:callback]     puts @greeting   end    # case 2   # in case, `callback` executed in rspec   # task :main   #   rake::task['rspec_before:callback'].execute   #   puts @greeting   # end end 

so, i'm not sure call :callback callback, it's more of dependency. callback implies happens after main task done, whereas when do

task main: [:callback] 

what you're saying depend on other task having run first. end changing name of that, though that's sample/throwaway name question. but, digress , i'll continue calling task :callback written answer.

---

the main issue here when call execute on rake task, task gets executed. because there may situations don't want or need call entire dependency chain. let's add task file:

desc "secondary task" task :secondary   @greeting = 'goodbye, cruel world'    rake::task['rspec_before:main'].execute end 

if run this, want main task output goodbye, cruel world, instead of hello, world , if call dependencies, main end calling :callback override our @greeting , end outputting hello, world.

there is, however, task call entire dependency chain: invoke:

desc "secondary task" task :secondary   @greeting = 'goodbye, cruel world'   rake::task['rspec_before:main'].invoke end 

if run task, we'll see hello, world instead of goodbye, cruel world. so, having said of this, mean rspec test? need change subject to:

subject { @rake['rspec_before:main'].invoke } 

because wanting run dependencies.

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