4 files changed, 39 insertions, 2 deletions
diff --git a/spec/ruby/core/false/case_compare_spec.rb b/spec/ruby/core/false/case_compare_spec.rb
new file mode 100644
index 0000000000..0bd0ab44ae
--- /dev/null
+++ b/spec/ruby/core/false/case_compare_spec.rb
@@ -0,0 +1,14 @@
+require_relative '../../spec_helper'
+
+describe "FalseClass#===" do
+  it "returns true for false" do
+    (false === false).should == true
+  end
+
+  it "returns false for non-false object" do
+    (false === 0).should == false
+    (false === "").should == false
+    (false === Object).should == false
+    (false === nil).should == false
+  end
+end
diff --git a/spec/ruby/core/false/falseclass_spec.rb b/spec/ruby/core/false/falseclass_spec.rb
index a944edd348..c018ef2421 100644
--- a/spec/ruby/core/false/falseclass_spec.rb
+++ b/spec/ruby/core/false/falseclass_spec.rb
@@ -2,13 +2,13 @@ require_relative '../../spec_helper'
 
 describe "FalseClass" do
   it ".allocate raises a TypeError" do
-    lambda do
+    -> do
       FalseClass.allocate
     end.should raise_error(TypeError)
   end
 
   it ".new is undefined" do
-    lambda do
+    -> do
       FalseClass.new
     end.should raise_error(NoMethodError)
   end
diff --git a/spec/ruby/core/false/singleton_method_spec.rb b/spec/ruby/core/false/singleton_method_spec.rb
new file mode 100644
index 0000000000..738794b46c
--- /dev/null
+++ b/spec/ruby/core/false/singleton_method_spec.rb
@@ -0,0 +1,15 @@
+require_relative '../../spec_helper'
+
+describe "FalseClass#singleton_method" do
+  ruby_version_is '3.3' do
+    it "raises regardless of whether FalseClass defines the method" do
+      -> { false.singleton_method(:foo) }.should raise_error(NameError)
+      begin
+        def (false).foo; end
+        -> { false.singleton_method(:foo) }.should raise_error(NameError)
+      ensure
+        FalseClass.send(:remove_method, :foo)
+      end
+    end
+  end
+end
diff --git a/spec/ruby/core/false/to_s_spec.rb b/spec/ruby/core/false/to_s_spec.rb
index 40853da88b..62f67f6f55 100644
--- a/spec/ruby/core/false/to_s_spec.rb
+++ b/spec/ruby/core/false/to_s_spec.rb
@@ -4,4 +4,12 @@ describe "FalseClass#to_s" do
   it "returns the string 'false'" do
     false.to_s.should == "false"
   end
+
+  it "returns a frozen string" do
+    false.to_s.should.frozen?
+  end
+
+  it "always returns the same string" do
+    false.to_s.should equal(false.to_s)
+  end
 end