1 files changed, 91 insertions, 0 deletions
diff --git a/spec/ruby/core/kernel/freeze_spec.rb b/spec/ruby/core/kernel/freeze_spec.rb
new file mode 100644
index 0000000000..079617dce4
--- /dev/null
+++ b/spec/ruby/core/kernel/freeze_spec.rb
@@ -0,0 +1,91 @@
+require_relative '../../spec_helper'
+require_relative 'fixtures/classes'
+
+describe "Kernel#freeze" do
+  it "prevents self from being further modified" do
+    o = mock('o')
+    o.frozen?.should == false
+    o.freeze
+    o.frozen?.should == true
+  end
+
+  it "returns self" do
+    o = Object.new
+    o.freeze.should.equal?(o)
+  end
+
+  describe "on integers" do
+    it "has no effect since they are already frozen" do
+      1.frozen?.should == true
+      1.freeze
+
+      bignum = bignum_value
+      bignum.frozen?.should == true
+      bignum.freeze
+    end
+  end
+
+  describe "on a Float" do
+    it "has no effect since it is already frozen" do
+      1.2.frozen?.should == true
+      1.2.freeze
+    end
+  end
+
+  describe "on a Symbol" do
+    it "has no effect since it is already frozen" do
+      :sym.frozen?.should == true
+      :sym.freeze
+    end
+  end
+
+  describe "on true, false and nil" do
+    it "has no effect since they are already frozen" do
+      nil.frozen?.should == true
+      true.frozen?.should == true
+      false.frozen?.should == true
+
+      nil.freeze
+      true.freeze
+      false.freeze
+    end
+  end
+
+  describe "on a Complex" do
+    it "has no effect since it is already frozen" do
+      c = Complex(1.3, 3.1)
+      c.frozen?.should == true
+      c.freeze
+    end
+  end
+
+  describe "on a Rational" do
+    it "has no effect since it is already frozen" do
+      r = Rational(1, 3)
+      r.frozen?.should == true
+      r.freeze
+    end
+  end
+
+  it "causes mutative calls to raise RuntimeError" do
+    o = Class.new do
+      def mutate; @foo = 1; end
+    end.new
+    o.freeze
+    -> {o.mutate}.should.raise(RuntimeError)
+  end
+
+  it "causes instance_variable_set to raise RuntimeError" do
+    o = Object.new
+    o.freeze
+    -> {o.instance_variable_set(:@foo, 1)}.should.raise(RuntimeError)
+  end
+
+  it "freezes an object's singleton class" do
+    o = Object.new
+    c = o.singleton_class
+    c.frozen?.should == false
+    o.freeze
+    c.frozen?.should == true
+  end
+end