Update tests, proper handling of return values

src/transformers/utils/chat_template_utils.py

@@ -36,9 +36,12 @@ def _convert_type_hints_to_json_schema(func):
     properties = {}
 
     signature = inspect.signature(func)
-    required = [
+    required = []
-        param_name for param_name, param in signature.parameters.items() if param.default == inspect.Parameter.empty
+    for param_name, param in signature.parameters.items():
-    ]
+        if param.annotation == inspect.Parameter.empty:
+            raise ValueError(f"Argument {param.name} is missing a type hint in function {func.__name__}")
+        if param.default == inspect.Parameter.empty:
+            required.append(param_name)
 
     for param_name, param_type in type_hints.items():
         if param_name == "return":
@@ -51,8 +54,7 @@ def _convert_type_hints_to_json_schema(func):
 
     return schema
 
-# TODO: Return types!! How are those even handled? Does it even matter? I should check what the different APIs do for this
+
-#       and also add tests
 def _parse_type_hint(hint):
     if (origin := get_origin(hint)) is not None:
         if origin is Union:

tests/utils/test_chat_template_utils.py

@@ -15,7 +15,15 @@ class JsonSchemaGeneratorTest(unittest.TestCase):
             return x
 
         schema = get_json_schema(fn)
-        expected_schema = {'name': 'fn', 'description': 'Test function', 'parameters': {'type': 'object', 'properties': {'x': {'type': 'integer', 'description': 'The input'}}, 'required': ['x']}}
+        expected_schema = {
+            "name": "fn",
+            "description": "Test function",
+            "parameters": {
+                "type": "object",
+                "properties": {"x": {"type": "integer", "description": "The input"}},
+                "required": ["x"],
+            },
+        }
         self.assertEqual(schema, expected_schema)
 
     def test_union(self):
@@ -28,7 +36,15 @@ class JsonSchemaGeneratorTest(unittest.TestCase):
             return x
 
         schema = get_json_schema(fn)
-        expected_schema = {'name': 'fn', 'description': 'Test function', 'parameters': {'type': 'object', 'properties': {'x': {'type': ['integer', 'number'], 'description': 'The input'}}, 'required': ['x']}}
+        expected_schema = {
+            "name": "fn",
+            "description": "Test function",
+            "parameters": {
+                "type": "object",
+                "properties": {"x": {"type": ["integer", "number"], "description": "The input"}},
+                "required": ["x"],
+            },
+        }
         self.assertEqual(schema, expected_schema)
 
     def test_optional(self):
@@ -41,7 +57,15 @@ class JsonSchemaGeneratorTest(unittest.TestCase):
             return x
 
         schema = get_json_schema(fn)
-        expected_schema = {'name': 'fn', 'description': 'Test function', 'parameters': {'type': 'object', 'properties': {'x': {'type': 'integer', 'description': 'The input', "nullable": True}}, 'required': ['x']}}
+        expected_schema = {
+            "name": "fn",
+            "description": "Test function",
+            "parameters": {
+                "type": "object",
+                "properties": {"x": {"type": "integer", "description": "The input", "nullable": True}},
+                "required": ["x"],
+            },
+        }
         self.assertEqual(schema, expected_schema)
 
     def test_default_arg(self):
@@ -54,7 +78,11 @@ class JsonSchemaGeneratorTest(unittest.TestCase):
             return x
 
         schema = get_json_schema(fn)
-        expected_schema = {'name': 'fn', 'description': 'Test function', 'parameters': {'type': 'object', 'properties': {'x': {'type': 'integer', 'description': 'The input'}}}}
+        expected_schema = {
+            "name": "fn",
+            "description": "Test function",
+            "parameters": {"type": "object", "properties": {"x": {"type": "integer", "description": "The input"}}},
+        }
         self.assertEqual(schema, expected_schema)
 
     def test_nested_list(self):
@@ -67,7 +95,21 @@ class JsonSchemaGeneratorTest(unittest.TestCase):
             return x
 
         schema = get_json_schema(fn)
-        expected_schema = {'name': 'fn', 'description': 'Test function', 'parameters': {'type': 'object', 'properties': {'x': {'type': 'array', 'items': {'type': 'array', 'items': {'type': ['integer', 'string']}}, 'description': 'The input'}}, 'required': ['x']}}
+        expected_schema = {
+            "name": "fn",
+            "description": "Test function",
+            "parameters": {
+                "type": "object",
+                "properties": {
+                    "x": {
+                        "type": "array",
+                        "items": {"type": "array", "items": {"type": ["integer", "string"]}},
+                        "description": "The input",
+                    }
+                },
+                "required": ["x"],
+            },
+        }
         self.assertEqual(schema, expected_schema)
 
     def test_multiple_arguments(self):
@@ -81,7 +123,18 @@ class JsonSchemaGeneratorTest(unittest.TestCase):
             return x
 
         schema = get_json_schema(fn)
-        expected_schema = {'name': 'fn', 'description': 'Test function', 'parameters': {'type': 'object', 'properties': {'x': {'type': 'integer', 'description': 'The input'}, 'y': {'type': 'string', 'description': 'Also the input'}}, 'required': ['x', 'y']}}
+        expected_schema = {
+            "name": "fn",
+            "description": "Test function",
+            "parameters": {
+                "type": "object",
+                "properties": {
+                    "x": {"type": "integer", "description": "The input"},
+                    "y": {"type": "string", "description": "Also the input"},
+                },
+                "required": ["x", "y"],
+            },
+        }
         self.assertEqual(schema, expected_schema)
 
     def test_multiple_complex_arguments(self):
@@ -95,7 +148,22 @@ class JsonSchemaGeneratorTest(unittest.TestCase):
             return x
 
         schema = get_json_schema(fn)
-        expected_schema = {'name': 'fn', 'description': 'Test function', 'parameters': {'type': 'object', 'properties': {'x': {'type': 'array', 'items': {'type': ['integer', 'number']}, 'description': 'The input'}, 'y': {'anyOf': [{'type': 'integer'}, {'type': 'string'}], 'nullable': True, 'description': 'Also the input'}}, 'required': ['x']}}
+        expected_schema = {
+            "name": "fn",
+            "description": "Test function",
+            "parameters": {
+                "type": "object",
+                "properties": {
+                    "x": {"type": "array", "items": {"type": ["integer", "number"]}, "description": "The input"},
+                    "y": {
+                        "anyOf": [{"type": "integer"}, {"type": "string"}],
+                        "nullable": True,
+                        "description": "Also the input",
+                    },
+                },
+                "required": ["x"],
+            },
+        }
         self.assertEqual(schema, expected_schema)
 
     def test_missing_docstring(self):
@@ -126,3 +194,25 @@ class JsonSchemaGeneratorTest(unittest.TestCase):
 
         with self.assertRaises(ValueError):
             get_json_schema(fn)
+
+    def test_return_value_has_no_effect(self):
+        # We ignore return values, so we want to make sure they don't affect the schema
+        def fn(x: int) -> int:
+            """
+            Test function
+
+            :param x: The input
+            """
+            return x
+
+        schema = get_json_schema(fn)
+        expected_schema = {
+            "name": "fn",
+            "description": "Test function",
+            "parameters": {
+                "type": "object",
+                "properties": {"x": {"type": "integer", "description": "The input"}},
+                "required": ["x"],
+            },
+        }
+        self.assertEqual(schema, expected_schema)