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diff --git a/spec/ruby/shared/complex/minus.rb b/spec/ruby/shared/complex/minus.rb
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+++ b/spec/ruby/shared/complex/minus.rb
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+require File.expand_path('../../../spec_helper', __FILE__)
+
+describe :complex_minus, shared: true do
+  describe "with Complex" do
+    it "subtracts both the real and imaginary components" do
+      (Complex(1, 2) - Complex(10, 20)).should == Complex(1 - 10, 2 - 20)
+      (Complex(1.5, 2.1) - Complex(100.2, -30.3)).should == Complex(1.5 - 100.2, 2.1 - (-30.3))
+    end
+  end
+
+  describe "with Integer" do
+    it "subtracts the real number from the real component of self" do
+      (Complex(1, 2) - 50).should == Complex(-49, 2)
+      (Complex(1, 2) - 50.5).should == Complex(-49.5, 2)
+    end
+  end
+
+  describe "with Object" do
+    it "tries to coerce self into other" do
+      value = Complex(3, 9)
+
+      obj = mock("Object")
+      obj.should_receive(:coerce).with(value).and_return([2, 5])
+      (value - obj).should == 2 - 5
+    end
+  end
+
+  describe "passed Numeric which responds to #real? with true" do
+    it "coerces the passed argument to the type of the real part and subtracts the resulting elements" do
+      n = mock_numeric('n')
+      n.should_receive(:real?).and_return(true)
+      n.should_receive(:coerce).with(1).and_return([1, 4])
+      (Complex(1, 2) - n).should == Complex(-3, 2)
+    end
+  end
+
+  describe "passed Numeric which responds to #real? with false" do
+    it "coerces the passed argument to Complex and subtracts the resulting elements" do
+      n = mock_numeric('n')
+      n.should_receive(:real?).and_return(false)
+      n.should_receive(:coerce).with(Complex(1, 2)).and_return([Complex(1, 2), Complex(3, 4)])
+      (Complex(1, 2) - n).should == Complex(-2, -2)
+    end
+  end
+end