1 files changed, 49 insertions, 0 deletions
diff --git a/spec/ruby/core/module/method_defined_spec.rb b/spec/ruby/core/module/method_defined_spec.rb
new file mode 100644
index 0000000000..d6206fa57e
--- /dev/null
+++ b/spec/ruby/core/module/method_defined_spec.rb
@@ -0,0 +1,49 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../fixtures/classes', __FILE__)
+
+describe "Module#method_defined?" do
+  it "returns true if a public or private method with the given name is defined in self, self's ancestors or one of self's included modules" do
+    # Defined in Child
+    ModuleSpecs::Child.method_defined?(:public_child).should == true
+    ModuleSpecs::Child.method_defined?("private_child").should == false
+    ModuleSpecs::Child.method_defined?(:accessor_method).should == true
+
+    # Defined in Parent
+    ModuleSpecs::Child.method_defined?("public_parent").should == true
+    ModuleSpecs::Child.method_defined?(:private_parent).should == false
+
+    # Defined in Module
+    ModuleSpecs::Child.method_defined?(:public_module).should == true
+    ModuleSpecs::Child.method_defined?(:protected_module).should == true
+    ModuleSpecs::Child.method_defined?(:private_module).should == false
+
+    # Defined in SuperModule
+    ModuleSpecs::Child.method_defined?(:public_super_module).should == true
+    ModuleSpecs::Child.method_defined?(:protected_super_module).should == true
+    ModuleSpecs::Child.method_defined?(:private_super_module).should == false
+  end
+
+  # unlike alias_method, module_function, public, and friends,
+  it "does not search Object or Kernel when called on a module" do
+    m = Module.new
+
+    m.method_defined?(:module_specs_public_method_on_kernel).should be_false
+  end
+
+  it "raises a TypeError when the given object is not a string/symbol/fixnum" do
+    c = Class.new
+    o = mock('123')
+
+    lambda { c.method_defined?(o) }.should raise_error(TypeError)
+
+    o.should_receive(:to_str).and_return(123)
+    lambda { c.method_defined?(o) }.should raise_error(TypeError)
+  end
+
+  it "converts the given name to a string using to_str" do
+    c = Class.new { def test(); end }
+    (o = mock('test')).should_receive(:to_str).and_return("test")
+
+    c.method_defined?(o).should == true
+  end
+end