CI. Run against Rails 4.2 on Ruby 2.7

Author: andrykonchin

.travis.yml

@@ -6,6 +6,7 @@ rvm:
   - ruby-2.4.6
   - ruby-2.5.5
   - ruby-2.6.3
+  - ruby-2.7.0
   - jruby-9.2.14.0
 gemfile:
   - gemfiles/rails_4_2.gemfile
@@ -16,15 +17,6 @@ gemfile:
 
 matrix:
   include:
-    # Ruby 2.7
-    # Rails works with Ruby 2.7 only from Rails 5.0
-    - rvm: ruby-2.7.0
-      gemfile: gemfiles/rails_5_0.gemfile
-    - rvm: ruby-2.7.0
-      gemfile: gemfiles/rails_5_1.gemfile
-    - rvm: ruby-2.7.0
-      gemfile: gemfiles/rails_5_2.gemfile
-
     # Rails 6.0
     # It requires Ruby 2.5 and above
     - rvm: ruby-2.5.3

Appraisals

@@ -2,6 +2,15 @@
 
 appraise 'rails-4-2' do
   gem 'activemodel', '~> 4.2.0'
+
+  # Add bigdecimal gem to support Ruby 2.7 and above:
+  # https://github.com/rails/rails/issues/34822
+
+  # Compatibility with Ruby versions:
+  # https://github.com/ruby/bigdecimal#which-version-should-you-select
+  #
+  # Actually bigdecimal 1.4.x works on all the Ruby versions till Ruby 3.0
+  gem 'bigdecimal', '~> 1.4.0', platform: :mri
 end
 
 appraise 'rails-5-0' do

gemfiles/rails_4_2.gemfile

@@ -1,11 +1,9 @@
-# frozen_string_literal: true
-
 # This file was generated by Appraisal
 
-source 'https://rubygems.org'
+source "https://rubygems.org"
 
-gem 'activemodel', '~> 4.2.0'
-gem 'nokogiri', '~> 1.6.8'
-gem 'pry-byebug', platforms: :ruby
+gem "pry-byebug", platforms: :ruby
+gem "activemodel", "~> 4.2.0"
+gem "bigdecimal", "~> 1.4.0", platform: :mri
 
-gemspec path: '../'
+gemspec path: "../"