Add a test case for ToolChoice="none"

Author: toshiakit

tests/topenAIChat.m

@@ -77,6 +77,12 @@ function errorsWhenPassingToolChoiceWithEmptyTools(testCase)
             testCase.verifyError(@()generate(chat,"input", ToolChoice="bla"), "llms:mustSetFunctionsForCall");
         end
 
+        function errorsWhenPassingToolChoiceWithNone(testCase)
+            functions = openAIFunction("funName");
+            chat = openAIChat(ApiKey="this-is-not-a-real-key",Tools=functions);
+            testCase.verifyWarningFree(@()generate(chat,"This is okay","ToolChoice","none"));
+        end
+
         function invalidInputsConstructor(testCase, InvalidConstructorInput)
             testCase.verifyError(@()openAIChat(InvalidConstructorInput.Input{:}), InvalidConstructorInput.Error);
         end