Fixed #35175 -- Made migraton writer preserve keyword-only arguments.

Thanks Gerald Goh for the report.

django/utils/inspect.py

@@ -16,13 +16,18 @@ def _get_callable_parameters(meth_or_func):
     return _get_func_parameters(func, remove_first=is_method)
 
 
+ARG_KINDS = frozenset(
+    {
+        inspect.Parameter.POSITIONAL_ONLY,
+        inspect.Parameter.KEYWORD_ONLY,
+        inspect.Parameter.POSITIONAL_OR_KEYWORD,
+    }
+)
+
+
 def get_func_args(func):
     params = _get_callable_parameters(func)
-    return [
+    return [param.name for param in params if param.kind in ARG_KINDS]
-        param.name
-        for param in params
-        if param.kind == inspect.Parameter.POSITIONAL_OR_KEYWORD
-    ]
 
 
 def get_func_full_args(func):

tests/custom_migration_operations/operations.py

@@ -68,6 +68,11 @@ class ArgsKwargsOperation(TestOperation):
         )
 
 
+class ArgsAndKeywordOnlyArgsOperation(ArgsKwargsOperation):
+    def __init__(self, arg1, arg2, *, kwarg1, kwarg2):
+        super().__init__(arg1, arg2, kwarg1=kwarg1, kwarg2=kwarg2)
+
+
 class ExpandArgsOperation(TestOperation):
     serialization_expand_args = ["arg"]
 

tests/migrations/test_writer.py

@@ -152,6 +152,24 @@ class OperationWriterTests(SimpleTestCase):
             "),",
         )
 
+    def test_keyword_only_args_signature(self):
+        operation = (
+            custom_migration_operations.operations.ArgsAndKeywordOnlyArgsOperation(
+                1, 2, kwarg1=3, kwarg2=4
+            )
+        )
+        buff, imports = OperationWriter(operation, indentation=0).serialize()
+        self.assertEqual(imports, {"import custom_migration_operations.operations"})
+        self.assertEqual(
+            buff,
+            "custom_migration_operations.operations.ArgsAndKeywordOnlyArgsOperation(\n"
+            "    arg1=1,\n"
+            "    arg2=2,\n"
+            "    kwarg1=3,\n"
+            "    kwarg2=4,\n"
+            "),",
+        )
+
     def test_nested_args_signature(self):
         operation = custom_migration_operations.operations.ArgsOperation(
             custom_migration_operations.operations.ArgsOperation(1, 2),

tests/postgres_tests/test_operations.py

@@ -4,6 +4,7 @@ from migrations.test_base import OperationTestBase
 
 from django.db import IntegrityError, NotSupportedError, connection, transaction
 from django.db.migrations.state import ProjectState
+from django.db.migrations.writer import OperationWriter
 from django.db.models import CheckConstraint, Index, Q, UniqueConstraint
 from django.db.utils import ProgrammingError
 from django.test import modify_settings, override_settings
@@ -393,6 +394,25 @@ class CreateCollationTests(PostgreSQLTestCase):
         self.assertEqual(len(captured_queries), 1)
         self.assertIn("DROP COLLATION", captured_queries[0]["sql"])
 
+    def test_writer(self):
+        operation = CreateCollation(
+            "sample_collation",
+            "und-u-ks-level2",
+            provider="icu",
+            deterministic=False,
+        )
+        buff, imports = OperationWriter(operation, indentation=0).serialize()
+        self.assertEqual(imports, {"import django.contrib.postgres.operations"})
+        self.assertEqual(
+            buff,
+            "django.contrib.postgres.operations.CreateCollation(\n"
+            "    name='sample_collation',\n"
+            "    locale='und-u-ks-level2',\n"
+            "    provider='icu',\n"
+            "    deterministic=False,\n"
+            "),",
+        )
+
 
 @unittest.skipUnless(connection.vendor == "postgresql", "PostgreSQL specific tests.")
 class RemoveCollationTests(PostgreSQLTestCase):