Rails/FilePath autocorrect shouldn't remove important trailing slash in dynamic string containing Rails.root #1177
Description
I'm trying to use Rails.root to remove it from an absolute filepath to result in a filepath relative to Rails.root.
my_abs_path = "/Users/me/rails_app/config/locales/text_en.yml" expected_relative_result = "config/locales/text_en.yml" my_abs_path.delete_prefix("#{Rails.root}/") == expected_relative_result # => trueExpected behavior
# this should be allowed by Rails/FilePath cop because the last / in /Users/me/rails_app/ must be deleted, not just /Users/me/rails_app my_abs_path.delete_prefix("#{Rails.root}/")Actual behavior
my_abs_path.delete_prefix("#{Rails.root}/") # raises Rails/FilePath, and is autocorrected to my_abs_path.delete_prefix("#{Rails.root.join('')}") # which raises Style/RedundantInterpolation, so we manually correct to my_abs_path.delete_prefix(Rails.root.join('').to_s) # which is wrong: actual = my_abs_path.delete_prefix(Rails.root.join('').to_s) actual == expected_relative_result # => false puts actual # => "/config/locales/text_en.yml" # so we try giving an argument to join, but still wrong because Rails.root.join never adds a trailing slash: actual = my_abs_path.delete_prefix(Rails.root.join('./').to_s) actual == expected_relative_result # => false puts actual # => "/config/locales/text_en.yml"Steps to reproduce the problem
Copy the below into a file, run RuboCop with autocorrect enabled and manually fix any other cops that are raised, then assert that the result is true.
rubocop-rails-filepath-test.rb
# where Rails.root is /Users/me/rails_app my_abs_path = "/Users/me/rails_app/config/locales/text_en.yml" expected_relative_result = "config/locales/text_en.yml" actual = my_abs_path.delete_prefix("#{Rails.root}/") if actual != expected_relative_result raise "Invalid autocorrection: #{actual.inspect} != #{expected_relative_result.inspect}" endrubocop -a rubocop-rails-filepath-test.rb rubocop -A rubocop-rails-filepath-test.rb # autofix Style/RedundantInterpolation bin/rails c < rubocop-rails-filepath-test.rbRuboCop version
1.57.2 (using Parser 3.2.2.4, rubocop-ast 1.30.0, running on ruby 3.0.6) [arm64-darwin21] - rubocop-rails 2.22.1 - rubocop-rspec 2.18.1