add tests

groovy/transpiler.py

@@ -508,10 +508,28 @@ def get_expr_type(self, node: ast.AST) -> type | None:
         return None
 
 
-def transpile(fn: Callable) -> str:
+def transpile(fn: Callable, validate: bool = False) -> str:
     """
     Transpiles a Python function to JavaScript and returns the JavaScript code as a string.
+
+    Parameters:
+        fn: The Python function to transpile.
+        validate: If True, the function will be validated to ensure it takes no arguments & only returns gradio component property updates.
+
+    Returns:
+        The JavaScript code as a string.
+
+    Raises:
+        TranspilerError: If the function cannot be transpiled or if the transpiled function is not valid.
     """
+    if validate:
+        sig = inspect.signature(fn)
+        if sig.parameters:
+            param_names = list(sig.parameters.keys())
+            raise TranspilerError(
+                message=f"Function must take no arguments, but got: {param_names}"
+            )
+
     try:
         source = inspect.getsource(fn)
         source = textwrap.dedent(source)

tests/test_transpiler.py

@@ -219,3 +219,26 @@ def filter_rows_by_term(data: list, search_term: str) -> list:
     return data.filter(row => row[0].includes(search_term));
 }"""
     assert transpile(filter_rows_by_term).strip() == expected.strip()
+
+
+def test_validate_no_arguments():
+    def no_args_function():
+        return gradio.Textbox(value="This is valid")
+
+    # This should pass validation
+    result = transpile(no_args_function, validate=True)
+    expected = """function no_args_function() {
+    return {"value": "This is valid", "__type__": "update"};
+}"""
+    assert result.strip() == expected.strip()
+
+
+def test_validate_with_arguments():
+    def function_with_args(text_input):
+        return gradio.Textbox(value=f"You entered: {text_input}")
+
+    # This should fail validation
+    with pytest.raises(TranspilerError) as e:
+        transpile(function_with_args, validate=True)
+
+    assert "text_input" in str(e.value)