Test against all versions of Rails 5 and Ruby

Later versions of Rails require higher ruby versions; early versions
of Ruby can't run recent Rails, and vice versa. This exclusion matrix
will get more complicated until we drop some compatibility.

Note that in order to avoid having to install a specific version of
bundler for each ruby version, we need to constraint the one installed
to a verson compatible with Ruby 2.1; the latest bundler on the 1.x
branch requires Ruby 2.3 or above.

In order to ensure we have the right version of sqlite3 (since a
specific version is required by these versions of active record), we
define it explicitly in the appraisals file. We can also use this to
add minitest for the Rails 3.2 build automatically.

Author: lazyatom

.travis.yml

@@ -1,16 +1,44 @@
 language: ruby
 rvm:
+  - 2.6
+  - 2.5
+  - 2.4
+  - 2.3
   - 2.2
   - 2.1
 cache: bundler
-before_install: gem install bundler
+before_install: gem install bundler -v 1.16.2
 gemfile:
   - gemfiles/rails_3.2.gemfile
   - gemfiles/rails_4.0.gemfile
   - gemfiles/rails_4.1.gemfile
   - gemfiles/rails_4.2.gemfile
   - gemfiles/rails_5.0.gemfile
+  - gemfiles/rails_5.1.gemfile
+  - gemfiles/rails_5.2.gemfile
 matrix:
   exclude:
   - rvm: 2.1
     gemfile: gemfiles/rails_5.0.gemfile
+  - rvm: 2.1
+    gemfile: gemfiles/rails_5.1.gemfile
+  - rvm: 2.1
+    gemfile: gemfiles/rails_5.2.gemfile
+  - rvm: 2.4
+    gemfile: gemfiles/rails_3.2.gemfile
+  - rvm: 2.4
+    gemfile: gemfiles/rails_4.0.gemfile
+  - rvm: 2.4
+    gemfile: gemfiles/rails_4.1.gemfile
+  - rvm: 2.5
+    gemfile: gemfiles/rails_3.2.gemfile
+  - rvm: 2.5
+    gemfile: gemfiles/rails_4.0.gemfile
+  - rvm: 2.5
+    gemfile: gemfiles/rails_4.1.gemfile
+  - rvm: 2.6
+    gemfile: gemfiles/rails_3.2.gemfile
+  - rvm: 2.6
+    gemfile: gemfiles/rails_4.0.gemfile
+  - rvm: 2.6
+    gemfile: gemfiles/rails_4.1.gemfile

Appraisals

@@ -1,15 +1,35 @@
 appraise "rails-3.2" do
+  gem "sqlite3", "~> 1.3.6"
   gem "activerecord", "~> 3.2.22"
+  gem "minitest"
 end
 
 appraise "rails-4.0" do
+  gem 'sqlite3', '~> 1.3.6'
   gem "activerecord", "~> 4.0.13"
 end
 
 appraise "rails-4.1" do
+  gem 'sqlite3', '~> 1.3.6'
   gem "activerecord", "~> 4.1.11"
 end
 
 appraise "rails-4.2" do
+  gem 'sqlite3', '~> 1.3.6'
   gem "activerecord", "~> 4.2.2"
 end
+
+appraise "rails-5.0" do
+  gem 'sqlite3', '~> 1.3.6'
+  gem "activerecord", "~> 5.0.0"
+end
+
+appraise "rails-5.1" do
+  gem 'sqlite3', '~> 1.3.6'
+  gem "activerecord", "~> 5.1.0"
+end
+
+appraise "rails-5.2" do
+  gem 'sqlite3', '~> 1.3.6'
+  gem "activerecord", "~> 5.2.0"
+end

gemfiles/rails_3.2.gemfile

@@ -3,7 +3,8 @@
 source "http://www.rubygems.org"
 
 gem "appraisal"
+gem "sqlite3", "~> 1.3.6"
 gem "activerecord", "~> 3.2.22"
-gem 'minitest' # To fix ruby 2.2 + rails 3.2 build
+gem "minitest"
 
 gemspec :path => "../"

gemfiles/rails_4.0.gemfile

@@ -3,6 +3,7 @@
 source "http://www.rubygems.org"
 
 gem "appraisal"
+gem "sqlite3", "~> 1.3.6"
 gem "activerecord", "~> 4.0.13"
 
 gemspec :path => "../"

gemfiles/rails_4.1.gemfile

@@ -3,6 +3,7 @@
 source "http://www.rubygems.org"
 
 gem "appraisal"
+gem "sqlite3", "~> 1.3.6"
 gem "activerecord", "~> 4.1.11"
 
 gemspec :path => "../"

gemfiles/rails_4.2.gemfile

@@ -3,6 +3,7 @@
 source "http://www.rubygems.org"
 
 gem "appraisal"
+gem "sqlite3", "~> 1.3.6"
 gem "activerecord", "~> 4.2.2"
 
 gemspec :path => "../"

gemfiles/rails_5.0.gemfile

@@ -3,6 +3,7 @@
 source "http://www.rubygems.org"
 
 gem "appraisal"
+gem "sqlite3", "~> 1.3.6"
 gem "activerecord", "~> 5.0.0"
 
 gemspec :path => "../"

gemfiles/rails_5.1.gemfile

@@ -0,0 +1,9 @@
+# This file was generated by Appraisal
+
+source "http://www.rubygems.org"
+
+gem "appraisal"
+gem "sqlite3", "~> 1.3.6"
+gem "activerecord", "~> 5.1.0"
+
+gemspec :path => "../"

gemfiles/rails_5.2.gemfile

@@ -0,0 +1,9 @@
+# This file was generated by Appraisal
+
+source "http://www.rubygems.org"
+
+gem "appraisal"
+gem "sqlite3", "~> 1.3.6"
+gem "activerecord", "~> 5.2.0"
+
+gemspec :path => "../"