1 files changed, 42 insertions, 0 deletions
diff --git a/spec/ruby/core/math/tan_spec.rb b/spec/ruby/core/math/tan_spec.rb
new file mode 100644
index 0000000000..0318ef8a14
--- /dev/null
+++ b/spec/ruby/core/math/tan_spec.rb
@@ -0,0 +1,42 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../fixtures/classes', __FILE__)
+
+describe "Math.tan" do
+  it "returns a float" do
+    Math.tan(1.35).should be_kind_of(Float)
+  end
+
+  it "returns the tangent of the argument" do
+    Math.tan(0.0).should == 0.0
+    Math.tan(-0.0).should == -0.0
+    Math.tan(4.22).should be_close(1.86406937682395, TOLERANCE)
+    Math.tan(-9.65).should be_close(-0.229109052606441, TOLERANCE)
+  end
+
+  it "returns NaN if called with +-Infinitty" do
+    Math.tan(infinity_value).nan?.should == true
+    Math.tan(-infinity_value).nan?.should == true
+  end
+
+  it "raises a TypeError if the argument cannot be coerced with Float()" do
+    lambda { Math.tan("test") }.should raise_error(TypeError)
+  end
+
+  it "returns NaN given NaN" do
+    Math.tan(nan_value).nan?.should be_true
+  end
+
+  it "raises a TypeError if the argument is nil" do
+    lambda { Math.tan(nil) }.should raise_error(TypeError)
+  end
+
+  it "accepts any argument that can be coerced with Float()" do
+    Math.tan(MathSpecs::Float.new).should be_close(1.5574077246549, TOLERANCE)
+  end
+end
+
+describe "Math#tan" do
+  it "is accessible as a private instance method" do
+    IncludesMath.new.send(:tan, 1.0).should be_close(1.5574077246549, TOLERANCE)
+  end
+end