1 files changed, 36 insertions, 0 deletions
diff --git a/spec/ruby/core/module/lt_spec.rb b/spec/ruby/core/module/lt_spec.rb
new file mode 100644
index 0000000000..ce0d25b5a2
--- /dev/null
+++ b/spec/ruby/core/module/lt_spec.rb
@@ -0,0 +1,36 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../fixtures/classes', __FILE__)
+
+describe "Module#<" do
+  it "returns true if self is a subclass of or includes the given module" do
+    (ModuleSpecs::Child < ModuleSpecs::Parent).should == true
+    (ModuleSpecs::Child < ModuleSpecs::Basic).should == true
+    (ModuleSpecs::Child < ModuleSpecs::Super).should == true
+    (ModuleSpecs::Super < ModuleSpecs::Basic).should == true
+  end
+
+  it "returns false if self is a superclass of or included by the given module" do
+    (ModuleSpecs::Parent < ModuleSpecs::Child).should be_false
+    (ModuleSpecs::Basic < ModuleSpecs::Child).should be_false
+    (ModuleSpecs::Super < ModuleSpecs::Child).should be_false
+    (ModuleSpecs::Basic < ModuleSpecs::Super).should be_false
+  end
+
+  it "returns false if self is the same as the given module" do
+    (ModuleSpecs::Child  < ModuleSpecs::Child).should == false
+    (ModuleSpecs::Parent < ModuleSpecs::Parent).should == false
+    (ModuleSpecs::Basic  < ModuleSpecs::Basic).should == false
+    (ModuleSpecs::Super  < ModuleSpecs::Super).should == false
+  end
+
+  it "returns nil if self is not related to the given module" do
+    (ModuleSpecs::Parent < ModuleSpecs::Basic).should == nil
+    (ModuleSpecs::Parent < ModuleSpecs::Super).should == nil
+    (ModuleSpecs::Basic  < ModuleSpecs::Parent).should == nil
+    (ModuleSpecs::Super  < ModuleSpecs::Parent).should == nil
+  end
+
+  it "raises a TypeError if the argument is not a class/module" do
+    lambda { ModuleSpecs::Parent < mock('x') }.should raise_error(TypeError)
+  end
+end