1 files changed, 30 insertions, 0 deletions
diff --git a/spec/ruby/library/cmath/math/shared/cos.rb b/spec/ruby/library/cmath/math/shared/cos.rb
new file mode 100644
index 0000000000..31cb5ab1e5
--- /dev/null
+++ b/spec/ruby/library/cmath/math/shared/cos.rb
@@ -0,0 +1,30 @@
+require_relative '../fixtures/classes'
+
+describe :complex_math_cos, shared: true do
+  it "returns the cosine of the argument expressed in radians" do
+    @object.send(:cos, CMath::PI).should be_close(-1.0, TOLERANCE)
+    @object.send(:cos, 0).should be_close(1.0, TOLERANCE)
+    @object.send(:cos, CMath::PI/2).should be_close(0.0, TOLERANCE)
+    @object.send(:cos, 3*Math::PI/2).should be_close(0.0, TOLERANCE)
+    @object.send(:cos, 2*Math::PI).should be_close(1.0, TOLERANCE)
+  end
+
+  it "returns the cosine for Complex numbers" do
+    @object.send(:cos, Complex(0, CMath::PI)).should be_close(Complex(11.5919532755215, 0.0), TOLERANCE)
+    @object.send(:cos, Complex(3, 4)).should be_close(Complex(-27.0349456030742, -3.85115333481178), TOLERANCE)
+  end
+end
+
+describe :complex_math_cos_bang, shared: true do
+  it "returns the cosine of the argument expressed in radians" do
+    @object.send(:cos!, CMath::PI).should be_close(-1.0, TOLERANCE)
+    @object.send(:cos!, 0).should be_close(1.0, TOLERANCE)
+    @object.send(:cos!, CMath::PI/2).should be_close(0.0, TOLERANCE)
+    @object.send(:cos!, 3*Math::PI/2).should be_close(0.0, TOLERANCE)
+    @object.send(:cos!, 2*Math::PI).should be_close(1.0, TOLERANCE)
+  end
+
+  it "raises a TypeError when passed a Complex number" do
+    -> { @object.send(:cos!, Complex(3, 4)) }.should raise_error(TypeError)
+  end
+end