1 files changed, 46 insertions, 2 deletions
diff --git a/spec/ruby/core/rational/minus_spec.rb b/spec/ruby/core/rational/minus_spec.rb
index 9e0f81556b..a61b62ebe6 100644
--- a/spec/ruby/core/rational/minus_spec.rb
+++ b/spec/ruby/core/rational/minus_spec.rb
@@ -1,7 +1,51 @@
-require_relative '../../shared/rational/minus'
+require_relative '../../spec_helper'
 require_relative '../../shared/rational/arithmetic_exception_in_coerce'
 
 describe "Rational#-" do
-  it_behaves_like :rational_minus, :-
   it_behaves_like :rational_arithmetic_exception_in_coerce, :-
+
+  it "calls #coerce on the passed argument with self" do
+    rational = Rational(3, 4)
+    obj = mock("Object")
+    obj.should_receive(:coerce).with(rational).and_return([1, 2])
+
+    rational - obj
+  end
+
+  it "calls #- on the coerced Rational with the coerced Object" do
+    rational = Rational(3, 4)
+
+    coerced_rational = mock("Coerced Rational")
+    coerced_rational.should_receive(:-).and_return(:result)
+
+    coerced_obj = mock("Coerced Object")
+
+    obj = mock("Object")
+    obj.should_receive(:coerce).and_return([coerced_rational, coerced_obj])
+
+    (rational - obj).should == :result
+  end
+end
+
+describe "Rational#- passed a Rational" do
+  it "returns the result of subtracting other from self as a Rational" do
+    (Rational(3, 4) - Rational(0, 1)).should eql(Rational(3, 4))
+    (Rational(3, 4) - Rational(1, 4)).should eql(Rational(1, 2))
+
+    (Rational(3, 4) - Rational(2, 1)).should eql(Rational(-5, 4))
+  end
+end
+
+describe "Rational#- passed a Float" do
+  it "returns the result of subtracting other from self as a Float" do
+    (Rational(3, 4) - 0.2).should eql(0.55)
+    (Rational(3, 4) - 2.5).should eql(-1.75)
+  end
+end
+
+describe "Rational#- passed an Integer" do
+  it "returns the result of subtracting other from self as a Rational" do
+    (Rational(3, 4) - 1).should eql(Rational(-1, 4))
+    (Rational(3, 4) - 2).should eql(Rational(-5, 4))
+  end
 end