1 files changed, 37 insertions, 11 deletions
diff --git a/spec/ruby/core/integer/plus_spec.rb b/spec/ruby/core/integer/plus_spec.rb
index 7e919a16db..38428e56c5 100644
--- a/spec/ruby/core/integer/plus_spec.rb
+++ b/spec/ruby/core/integer/plus_spec.rb
@@ -2,20 +2,14 @@ require_relative '../../spec_helper'
 require_relative 'shared/arithmetic_coerce'
 
 describe "Integer#+" do
-  ruby_version_is "2.4"..."2.5" do
-    it_behaves_like :integer_arithmetic_coerce_rescue, :+
-  end
-
-  ruby_version_is "2.5" do
-    it_behaves_like :integer_arithmetic_coerce_not_rescue, :+
-  end
+  it_behaves_like :integer_arithmetic_coerce_not_rescue, :+
 
   context "fixnum" do
     it "returns self plus the given Integer" do
       (491 + 2).should == 493
       (90210 + 10).should == 90220
 
-      (9 + bignum_value).should == 9223372036854775817
+      (9 + bignum_value).should == 18446744073709551625
       (1001 + 5.219).should == 1006.219
     end
 
@@ -35,9 +29,9 @@ describe "Integer#+" do
     end
 
     it "returns self plus the given Integer" do
-      (@bignum + 4).should == 9223372036854775888
-      (@bignum + 4.2).should be_close(9223372036854775888.2, TOLERANCE)
-      (@bignum + bignum_value(3)).should == 18446744073709551695
+      (@bignum + 4).should == 18446744073709551696
+      (@bignum + 4.2).should be_close(18446744073709551696.2, TOLERANCE)
+      (@bignum + bignum_value(3)).should == 36893488147419103311
     end
 
     it "raises a TypeError when given a non-Integer" do
@@ -46,4 +40,36 @@ describe "Integer#+" do
       -> { @bignum + :symbol}.should raise_error(TypeError)
     end
   end
+
+  it "can be redefined" do
+    code = <<~RUBY
+      class Integer
+        alias_method :old_plus, :+
+        def +(other)
+          self - other
+        end
+      end
+      result = 1 + 2
+      Integer.alias_method :+, :old_plus
+      print result
+    RUBY
+    ruby_exe(code).should == "-1"
+  end
+
+  it "coerces the RHS and calls #coerce" do
+    obj = mock("integer plus")
+    obj.should_receive(:coerce).with(6).and_return([6, 3])
+    (6 + obj).should == 9
+  end
+
+  it "coerces the RHS and calls #coerce even if it's private" do
+    obj = Object.new
+    class << obj
+      private def coerce(n)
+        [n, 3]
+      end
+    end
+
+    (6 + obj).should == 9
+  end
 end