1 files changed, 41 insertions, 2 deletions
diff --git a/spec/ruby/core/thread/thread_variable_spec.rb b/spec/ruby/core/thread/thread_variable_spec.rb
index 6bd1950c04..1b021e9404 100644
--- a/spec/ruby/core/thread/thread_variable_spec.rb
+++ b/spec/ruby/core/thread/thread_variable_spec.rb
@@ -10,12 +10,51 @@ describe "Thread#thread_variable?" do
   end
 
   it "returns false if the thread variables do not contain 'key'" do
-    @t.thread_variable_set :a, 2
+    @t.thread_variable_set(:a, 2)
     @t.thread_variable?(:b).should be_false
   end
 
   it "returns true if the thread variables contain 'key'" do
-    @t.thread_variable_set :a, 2
+    @t.thread_variable_set(:a, 2)
     @t.thread_variable?(:a).should be_true
   end
+
+  it "accepts String and Symbol keys interchangeably" do
+    @t.thread_variable?('a').should be_false
+    @t.thread_variable?(:a).should be_false
+
+    @t.thread_variable_set(:a, 49)
+
+    @t.thread_variable?('a').should be_true
+    @t.thread_variable?(:a).should be_true
+  end
+
+  it "converts a key that is neither String nor Symbol with #to_str" do
+    key = mock('key')
+    key.should_receive(:to_str).and_return('a')
+    @t.thread_variable_set(:a, 49)
+    @t.thread_variable?(key).should be_true
+  end
+
+  it "does not raise FrozenError if the thread is frozen" do
+    @t.freeze
+    @t.thread_variable?(:a).should be_false
+  end
+
+  it "raises a TypeError if the key is neither Symbol nor String when thread variables are already set" do
+    @t.thread_variable_set(:a, 49)
+    -> { @t.thread_variable?(123) }.should raise_error(TypeError, /123 is not a symbol/)
+  end
+
+  ruby_version_is '3.4' do
+    it "raises a TypeError if the key is neither Symbol nor String when no thread variables are set" do
+      -> { @t.thread_variable?(123) }.should raise_error(TypeError, /123 is not a symbol/)
+    end
+
+    it "raises a TypeError if the key is neither Symbol nor String without calling #to_sym" do
+      key = mock('key')
+      key.should_not_receive(:to_sym)
+      -> { @t.thread_variable?(key) }.should raise_error(TypeError, /#{Regexp.escape(key.inspect)} is not a symbol/)
+    end
+  end
 end