Merge pull request #380 from RickCSong/master

Fix compatibility issues for Ruby 2.4.0

Author: liveh2o

.travis.yml

@@ -22,6 +22,7 @@ rvm:
   - 2.2
   - 2.2.2
   - 2.3
+  - 2.4
   - jruby-9.1.7.0
   - rbx-2
 env:

lib/protobuf/enum.rb

@@ -259,10 +259,16 @@ def initialize(parent_class, name, tag)
       super(tag)
     end
 
-    # Overriding the class so ActiveRecord/Arel visitor will visit the enum as a Fixnum
+    # Overriding the class so ActiveRecord/Arel visitor will visit the enum as an
+    # Integer.
     #
     def class
-      Fixnum
+      # This is done for backward compatibility for < 2.4.0. This ensures that
+      # if Ruby version >= 2.4.0, this will return Integer. If below, then will
+      # return Fixnum.
+      #
+      # This prevents the constant deprecation warnings on Fixnum.
+      tag.class
     end
 
     def inspect

spec/lib/protobuf/enum_spec.rb

@@ -214,7 +214,7 @@
   end
 
   subject { Test::EnumTestType::ONE }
-  specify { expect(subject.class).to eq(Fixnum) }
+  specify { expect(subject.class).to eq(1.class) }
   specify { expect(subject.parent_class).to eq(Test::EnumTestType) }
   specify { expect(subject.name).to eq(:ONE) }
   specify { expect(subject.tag).to eq(1) }