Make i18n dependency optional

.github/workflows/test.yml

@@ -24,3 +24,10 @@ jobs:
  - run: bundle install --jobs=3 --retry=3 --path=vendor/bundle
  - run: bundle exec rake spec
  continue-on-error: ${{ matrix.entry.allowed-failure }}
+ - name: Specs for when the i18n gem is not available
+ run: |
+ cd spec_i18n
+ bundle install --jobs=3 --retry=3
+ pwd
+ bundle exec rake spec
+ continue-on-error: ${{ matrix.entry.allowed-failure }}

CHANGELOG.md

@@ -1,5 +1,6 @@
 ### 1.0.0 (Next)
 
+* [#41](https://github.com/dblock/ruby-enum/pull/41): Make i18n dependency optional - [@peterfication](https://github.com/peterfication).
 * [#43](https://github.com/dblock/ruby-enum/pull/43): Add exhaustive case matcher - [@peterfication](https://github.com/peterfication).
 * [#40](https://github.com/dblock/ruby-enum/pull/39): Enable new Rubocop cops and address/allowlist lints - [@petergoldstein](https://github.com/petergoldstein).
 * [#39](https://github.com/dblock/ruby-enum/pull/39): Require Ruby >= 2.7 - [@petergoldstein](https://github.com/petergoldstein).

README.md

@@ -25,6 +25,7 @@ Enum-like behavior for Ruby, heavily inspired by [this](http://www.rubyfleebie.c
  - [Duplicate enumerator keys or duplicate values](#duplicate-enumerator-keys-or-duplicate-values)
  - [Inheritance](#inheritance)
  - [Exhaustive case matcher](#exhaustive-case-matcher)
+ - [I18n support](#i18n-support)
 - [Benchmarks](#benchmarks)
 - [Contributing](#contributing)
 - [Copyright and License](#copyright-and-license)
@@ -300,6 +301,15 @@ Color.Case(color, {
 })
 ```
 
+### I18n support
+
+This gem has an optional dependency to `i18n`. If it's available, the error messages will have a nice description and can be translated. If it's not available, the errors will only contain the message keys.
+
+```ruby
+# Add this to your Gemfile if you want to have a nice error description instead of just a message key.
+gem "i18n"
+```
+
 ## Benchmarks
 
 Benchmark scripts are defined in the [`benchmarks`](benchmarks) folder and can be run with Rake:

lib/ruby-enum.rb

@@ -1,12 +1,23 @@
 # frozen_string_literal: true
 
-require 'i18n'
-
 require 'ruby-enum/version'
 require 'ruby-enum/enum'
 require 'ruby-enum/enum/case'
+require 'ruby-enum/enum/i18n_mock'
+
+# Try to load the I18n gem and provide a mock if it is not available.
+begin
+ require 'i18n'
+ Ruby::Enum.i18n = I18n
+rescue LoadError
+ # I18n is not available
+ # :nocov:
+ # Tests for this loading are in the spec_i18n folder
+ Ruby::Enum.i18n = Ruby::Enum::I18nMock
+ # :nocov:
+end
 
-I18n.load_path << File.join(File.dirname(__FILE__), 'config', 'locales', 'en.yml')
+Ruby::Enum.i18n.load_path << File.join(File.dirname(__FILE__), 'config', 'locales', 'en.yml')
 
 require 'ruby-enum/errors/base'
 require 'ruby-enum/errors/uninitialized_constant_error'

lib/ruby-enum/enum.rb

@@ -2,6 +2,11 @@
 
 module Ruby
  module Enum
+ class << self
+ # Needed for I18n mock
+ attr_accessor :i18n
+ end
+
  attr_reader :key, :value
 
  def initialize(key, value)

lib/ruby-enum/enum/i18n_mock.rb

@@ -0,0 +1,19 @@
+# frozen_string_literal: true
+
+# :nocov:
+module Ruby
+ module Enum
+ ##
+ # Mock I18n module in case the i18n gem is not available.
+ module I18nMock
+ def self.load_path
+ []
+ end
+
+ def self.translate(key, _options = {})
+ key
+ end
+ end
+ end
+end
+# :nocov:

lib/ruby-enum/errors/base.rb

@@ -39,7 +39,7 @@ def compose_message(key, attributes = {})
  #
  # Returns a localized error message string.
  def translate(key, options)
- ::I18n.translate("#{BASE_KEY}.#{key}", locale: :en, **options).strip
+ Ruby::Enum.i18n.translate("#{BASE_KEY}.#{key}", locale: :en, **options).strip
  end
 
  # Create the problem.

ruby-enum.gemspec

@@ -16,6 +16,5 @@ Gem::Specification.new do |s|
  s.homepage = 'http://github.com/dblock/ruby-enum'
  s.licenses = ['MIT']
  s.summary = 'Enum-like behavior for Ruby.'
- s.add_dependency 'i18n'
  s.metadata['rubygems_mfa_required'] = 'true'
 end

spec/ruby-enum/enum_spec.rb

@@ -23,8 +23,24 @@ class SecondSubclass < FirstSubclass
  expect(Colors::GREEN).to eq 'green'
  end
 
- it 'raises UninitializedConstantError on an invalid constant' do
- expect { Colors::ANYTHING }.to raise_error Ruby::Enum::Errors::UninitializedConstantError, /The constant Colors::ANYTHING has not been defined./
+ context 'when the i18n gem is loaded' do
+ it 'raises UninitializedConstantError on an invalid constant' do
+ expect do
+ Colors::ANYTHING
+ end.to raise_error Ruby::Enum::Errors::UninitializedConstantError, /The constant Colors::ANYTHING has not been defined./
+ end
+ end
+
+ context 'when the i18n gem is not loaded' do
+ before do
+ allow(described_class).to receive(:i18n).and_return(Ruby::Enum::I18nMock)
+ end
+
+ it 'raises UninitializedConstantError on an invalid constant' do
+ expect do
+ Colors::ANYTHING
+ end.to raise_error Ruby::Enum::Errors::UninitializedConstantError, /ruby.enum.errors.messages.uninitialized_constant.summary/
+ end
  end
 
  describe '#each' do
@@ -151,22 +167,54 @@ class SecondSubclass < FirstSubclass
  end
 
  context 'when a duplicate key is used' do
- it 'raises DuplicateKeyError' do
- expect do
- Colors.class_eval do
- define :RED, 'some'
- end
- end.to raise_error Ruby::Enum::Errors::DuplicateKeyError, /The constant Colors::RED has already been defined./
+ context 'when the i18n gem is loaded' do
+ it 'raises DuplicateKeyError' do
+ expect do
+ Colors.class_eval do
+ define :RED, 'some'
+ end
+ end.to raise_error Ruby::Enum::Errors::DuplicateKeyError, /The constant Colors::RED has already been defined./
+ end
+ end
+
+ context 'when the i18n gem is not loaded' do
+ before do
+ allow(described_class).to receive(:i18n).and_return(Ruby::Enum::I18nMock)
+ end
+
+ it 'raises DuplicateKeyError' do
+ expect do
+ Colors.class_eval do
+ define :RED, 'some'
+ end
+ end.to raise_error Ruby::Enum::Errors::DuplicateKeyError, /ruby.enum.errors.messages.duplicate_key.message/
+ end
  end
  end
 
  context 'when a duplicate value is used' do
- it 'raises a DuplicateValueError' do
- expect do
- Colors.class_eval do
- define :Other, 'red'
- end
- end.to raise_error Ruby::Enum::Errors::DuplicateValueError, /The value red has already been defined./
+ context 'when the i18n gem is loaded' do
+ it 'raises a DuplicateValueError' do
+ expect do
+ Colors.class_eval do
+ define :Other, 'red'
+ end
+ end.to raise_error Ruby::Enum::Errors::DuplicateValueError, /The value red has already been defined./
+ end
+ end
+
+ context 'when the i18n gem is not loaded' do
+ before do
+ allow(described_class).to receive(:i18n).and_return(Ruby::Enum::I18nMock)
+ end
+
+ it 'raises a DuplicateValueError' do
+ expect do
+ Colors.class_eval do
+ define :Other, 'red'
+ end
+ end.to raise_error Ruby::Enum::Errors::DuplicateValueError, /ruby.enum.errors.messages.duplicate_value.summary/
+ end
  end
  end
 

spec_i18n/Gemfile

@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+source 'http://rubygems.org'
+
+gemspec path: '../', name: 'ruby-enum'
+
+# This Gemfile should not include any gem that has i18n as a dependency.
+gem 'rake'
+gem 'rspec', '~> 3.0'

spec_i18n/Rakefile

@@ -0,0 +1,12 @@
+# frozen_string_literal: true
+
+require 'rubygems'
+
+require 'rspec/core'
+require 'rspec/core/rake_task'
+
+RSpec::Core::RakeTask.new(:spec) do |spec|
+ spec.pattern = FileList['spec/**/*_spec.rb']
+end
+
+task default: %i[spec]

spec_i18n/spec/i18n_spec.rb

@@ -0,0 +1,52 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+test_class = Class.new do
+ include Ruby::Enum
+
+ define :RED, 'red'
+ define :GREEN, 'green'
+end
+
+describe Ruby::Enum do
+ context 'when the i18n gem is not loaded' do
+ it 'raises UninitializedConstantError on an invalid constant' do
+ expect do
+ test_class::ANYTHING
+ end.to raise_error Ruby::Enum::Errors::UninitializedConstantError, /ruby.enum.errors.messages.uninitialized_constant.summary/
+ end
+ end
+
+ context 'when a duplicate key is used' do
+ context 'when the i18n gem is not loaded' do
+ before do
+ allow(described_class).to receive(:i18n).and_return(Ruby::Enum::I18nMock)
+ end
+
+ it 'raises DuplicateKeyError' do
+ expect do
+ test_class.class_eval do
+ define :RED, 'some'
+ end
+ end.to raise_error Ruby::Enum::Errors::DuplicateKeyError, /ruby.enum.errors.messages.duplicate_key.message/
+ end
+ end
+ end
+
+ context 'when a duplicate value is used' do
+ context 'when the i18n gem is not loaded' do
+ before do
+ allow(described_class).to receive(:i18n).and_return(Ruby::Enum::I18nMock)
+ end
+
+ it 'raises a DuplicateValueError' do
+ expect do
+ test_class.class_eval do
+ define :Other, 'red'
+ end
+ end.to raise_error Ruby::Enum::Errors::DuplicateValueError, /ruby.enum.errors.messages.duplicate_value.summary/
+ end
+ end
+ end
+end

spec_i18n/spec/spec_helper.rb

@@ -0,0 +1,8 @@
+# frozen_string_literal: true
+
+$LOAD_PATH.unshift(File.join(File.dirname(__FILE__), '..', '..', 'lib'))
+
+require 'rubygems'
+
+require 'rspec'
+require 'ruby-enum'