Relative File Path in RSpec

Question

I have a RSpec test for a class in /lib/classes which needs access to a zip file (no upload). The file is stored in /spec/fixtures/files/test.zip. How do I input the correct path so its environment agnostic, i.e. without absolute path?

Answer 1

I've tackled this issue recently and here's what I came up with:

Define a constant in your spec_helper.rb (or equivalent) pointing to RSpec root:

RSPEC_ROOT = File.dirname __FILE__

Use this variable in your *_spec.rb (or equivalent) test files:

require 'spec_helper'

File.open("#{RSPEC_ROOT}/resources/example_data.json")

Why this solution?

• It doesn't make use of the location of the test file which may be subject to change (spec_helper is likely not)
• It doesn't require any additions to test files other than the already existing require 'spec_helper'
• It doesn't depend on Rails (unlike Rails.root)

Here's a Gist: https://gist.github.com/thisismydesign/9dc142f89b82a07e413a45a5d2983b07

Answer 2

As far as I know (from looking every month or two) there is no better way that building something in spec_helper that uses the __FILE__ value to grab the path to a know bit of content, then build your own helpers on top of that.

You can obviously use a path relative to __FILE__ in the individual *_spec.rb file as well.

Answer 3

Rails.root will give you the app root, so

Rails.root.join "spec/fixtures/files/test.zip"

will give you the absolute path of your file, agnostic of the location of the app on your hard drive.