Question

I have two files in two different directories:

module MyModule
  def my_method path
    p File.join (File.dirname __FILE__), path
  end
end

and

require_relative '../modules/mymodule' # definition of MyModule
class MyClass
  extend MyModule
  my_method 'my_file.yml'
end

I am getting output like my_home_dir/modules/my_file.yml but I want it to be my_home_dir/files/my_file.yml where files is the name of the directory where MyClass is defined.

I know I can use full path when I call my_method but is there a way for imported files to still have __FILE__ set to the name of the importing file?

Basically in my_method I need to have the full path of the file and I want to pass just a path relative to my calling file’s path.

Answer 1

__FILE__ always is the name of the file containing the __FILE__ variable, so saying my_method will always return where my_method is defined, not where MyClass calls it.

You can probably get at the information you want using caller:

module MyModule
  def my_method path
    p caller
  end
end

include MyModule # definition of MyModule
class MyClass
  extend MyModule
  my_method 'my_file.yml'
end

my_class = MyClass.new

Which outputs:

["test.rb:10:in `<class:MyClass>'", "test.rb:8:in `<main>'"]

---

Edit:

the caller array has only file names without paths…

Well, I’d hoped you’d know how to work around that but….

This is in test.rb:

require './test2'
class MyClass
  extend MyModule
  my_method __FILE__, 'my_file.yml'
end

my_class = MyClass.new

This is in test2.rb:

module MyModule
  def my_method path, file
    dir = File.dirname(path)
    p caller.map{ |c| File.join(dir, c) }
  end
end

Running test.rb outputs:

["./test.rb:4:in `<class:MyClass>'", "./test.rb:2:in `<main>'"]