1 files changed, 107 insertions, 0 deletions
diff --git a/spec/ruby/core/module/remove_const_spec.rb b/spec/ruby/core/module/remove_const_spec.rb
new file mode 100644
index 0000000000..35a9d65105
--- /dev/null
+++ b/spec/ruby/core/module/remove_const_spec.rb
@@ -0,0 +1,107 @@
+require_relative '../../spec_helper'
+require_relative '../../fixtures/constants'
+
+describe "Module#remove_const" do
+  it "removes the constant specified by a String or Symbol from the receiver's constant table" do
+    ConstantSpecs::ModuleM::CS_CONST252 = :const252
+    ConstantSpecs::ModuleM::CS_CONST252.should == :const252
+
+    ConstantSpecs::ModuleM.send :remove_const, :CS_CONST252
+    -> { ConstantSpecs::ModuleM::CS_CONST252 }.should raise_error(NameError)
+
+    ConstantSpecs::ModuleM::CS_CONST253 = :const253
+    ConstantSpecs::ModuleM::CS_CONST253.should == :const253
+
+    ConstantSpecs::ModuleM.send :remove_const, "CS_CONST253"
+    -> { ConstantSpecs::ModuleM::CS_CONST253 }.should raise_error(NameError)
+  end
+
+  it "returns the value of the removed constant" do
+    ConstantSpecs::ModuleM::CS_CONST254 = :const254
+    ConstantSpecs::ModuleM.send(:remove_const, :CS_CONST254).should == :const254
+  end
+
+  it "raises a NameError and does not call #const_missing if the constant is not defined" do
+    ConstantSpecs.should_not_receive(:const_missing)
+    -> { ConstantSpecs.send(:remove_const, :Nonexistent) }.should raise_error(NameError)
+  end
+
+  it "raises a NameError and does not call #const_missing if the constant is not defined directly in the module" do
+    begin
+      ConstantSpecs::ModuleM::CS_CONST255 = :const255
+      ConstantSpecs::ContainerA::CS_CONST255.should == :const255
+      ConstantSpecs::ContainerA.should_not_receive(:const_missing)
+
+      -> do
+        ConstantSpecs::ContainerA.send :remove_const, :CS_CONST255
+      end.should raise_error(NameError)
+    ensure
+      ConstantSpecs::ModuleM.send :remove_const, "CS_CONST255"
+    end
+  end
+
+  it "raises a NameError if the name does not start with a capital letter" do
+    -> { ConstantSpecs.send :remove_const, "name" }.should raise_error(NameError)
+  end
+
+  it "raises a NameError if the name starts with a non-alphabetic character" do
+    -> { ConstantSpecs.send :remove_const, "__CONSTX__" }.should raise_error(NameError)
+    -> { ConstantSpecs.send :remove_const, "@Name" }.should raise_error(NameError)
+    -> { ConstantSpecs.send :remove_const, "!Name" }.should raise_error(NameError)
+    -> { ConstantSpecs.send :remove_const, "::Name" }.should raise_error(NameError)
+  end
+
+  it "raises a NameError if the name contains non-alphabetic characters except '_'" do
+    ConstantSpecs::ModuleM::CS_CONST256 = :const256
+    ConstantSpecs::ModuleM.send :remove_const, "CS_CONST256"
+    -> { ConstantSpecs.send :remove_const, "Name=" }.should raise_error(NameError)
+    -> { ConstantSpecs.send :remove_const, "Name?" }.should raise_error(NameError)
+  end
+
+  it "calls #to_str to convert the given name to a String" do
+    ConstantSpecs::CS_CONST257 = :const257
+    name = mock("CS_CONST257")
+    name.should_receive(:to_str).and_return("CS_CONST257")
+    ConstantSpecs.send(:remove_const, name).should == :const257
+  end
+
+  it "raises a TypeError if conversion to a String by calling #to_str fails" do
+    name = mock('123')
+    -> { ConstantSpecs.send :remove_const, name }.should raise_error(TypeError)
+
+    name.should_receive(:to_str).and_return(123)
+    -> { ConstantSpecs.send :remove_const, name }.should raise_error(TypeError)
+  end
+
+  it "is a private method" do
+    Module.private_methods.should include(:remove_const)
+  end
+
+  it "returns nil when removing autoloaded constant" do
+    ConstantSpecs.autoload :AutoloadedConstant, 'a_file'
+    ConstantSpecs.send(:remove_const, :AutoloadedConstant).should be_nil
+  end
+
+  it "updates the constant value" do
+    module ConstantSpecs::RemovedConstantUpdate
+      module M
+        FOO = 'm'
+      end
+
+      module A
+        include M
+        FOO = 'a'
+        def self.foo
+          FOO
+        end
+      end
+
+      A.foo.should == 'a'
+
+      A.send(:remove_const,:FOO)
+      A.foo.should == 'm'
+    end
+  ensure
+    ConstantSpecs.send(:remove_const, :RemovedConstantUpdate)
+  end
+end