Verify Rails 5.2 support using Travis CI.

.travis.yml

@@ -9,6 +9,10 @@ rvm:
   - 2.0
 
 env:
+  - RAILS=5-2-stable DB=sqlite3
+  - RAILS=5-2-stable DB=mysql
+  - RAILS=5-2-stable DB=postgres
+
   - RAILS=5-0-stable DB=sqlite3
   - RAILS=5-0-stable DB=mysql
   - RAILS=5-0-stable DB=postgres
@@ -35,6 +39,13 @@ env:
 
 matrix:
   exclude:
+    - rvm: 2.1.10
+      env: RAILS=5-2-stable DB=sqlite3
+    - rvm: 2.1.10
+      env: RAILS=5-2-stable DB=mysql
+    - rvm: 2.1.10
+      env: RAILS=5-2-stable DB=postgres
+
     - rvm: 2.1.10
       env: RAILS=5-0-stable DB=sqlite3
     - rvm: 2.1.10
@@ -42,6 +53,13 @@ matrix:
     - rvm: 2.1.10
       env: RAILS=5-0-stable DB=postgres
 
+    - rvm: 2.0
+      env: RAILS=5-2-stable DB=sqlite3
+    - rvm: 2.0
+      env: RAILS=5-2-stable DB=mysql
+    - rvm: 2.0
+      env: RAILS=5-2-stable DB=postgres
+
     - rvm: 2.0
       env: RAILS=5-0-stable DB=sqlite3
     - rvm: 2.0

Gemfile

@@ -38,6 +38,9 @@ else
   if rails == '3-0-stable'
     gem 'mysql2', '< 0.3'
   end
+  if rails == '5-2-stable'
+    gem 'mysql2', '~> 0.4.4'
+  end
 end
 
 if ENV['DB'] =~ /mongoid4/