Add support for Python 3.12 (#308)

There were a couple of minor fixes we had to do in order to support
Python 3.12. In addition, we had to use more up-to-date versions of mypy
and pylint for Python versions >= 3.12.

Author: mristin

.github/workflows/ci.yml

@@ -12,7 +12,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: ['3.8', '3.9', '3.10', '3.11']
+        python-version: ['3.8', '3.9', '3.10', '3.11', '3.12']
 
     steps:
       - uses: actions/checkout@master
@@ -26,6 +26,8 @@ jobs:
         run: |
           python3 -m pip install --upgrade pip
           pip3 install --upgrade coveralls
+          # Python >=3.12 does not ship setuptools with pip anymore.
+          pip3 install setuptools
           pip3 install -e .[dev]
 
       - name: Run checks

icontract/_recompute.py

@@ -232,7 +232,7 @@ def _translate_all_expression_to_a_module(
             )  # type: Union[ast.FunctionDef, ast.AsyncFunctionDef]
 
             module_node = ast.Module(body=[func_def_node])
-        else:
+        elif sys.version_info < (3, 12):
             func_def_node = ast.FunctionDef(
                 name=generated_function_name,
                 args=ast.arguments(
@@ -248,6 +248,24 @@ def _translate_all_expression_to_a_module(
                 body=block,
             )
 
+            module_node = ast.Module(body=[func_def_node], type_ignores=[])
+        else:
+            func_def_node = ast.FunctionDef(
+                name=generated_function_name,
+                args=ast.arguments(
+                    args=args,
+                    posonlyargs=[],
+                    kwonlyargs=[],
+                    kw_defaults=[],
+                    defaults=[],
+                    vararg=None,
+                    kwarg=None,
+                ),
+                body=block,
+                decorator_list=[],
+                type_params=[],
+            )
+
             module_node = ast.Module(body=[func_def_node], type_ignores=[])
     else:
         if sys.version_info < (3, 8):
@@ -266,6 +284,23 @@ def _translate_all_expression_to_a_module(
             )
 
             module_node = ast.Module(body=[async_func_def_node])
+        elif sys.version_info < (3, 12):
+            async_func_def_node = ast.AsyncFunctionDef(
+                name=generated_function_name,
+                args=ast.arguments(
+                    args=args,
+                    posonlyargs=[],
+                    kwonlyargs=[],
+                    kw_defaults=[],
+                    defaults=[],
+                    vararg=None,
+                    kwarg=None,
+                ),
+                decorator_list=[],
+                body=block,
+            )
+
+            module_node = ast.Module(body=[async_func_def_node], type_ignores=[])
         else:
             async_func_def_node = ast.AsyncFunctionDef(
                 name=generated_function_name,
@@ -280,6 +315,7 @@ def _translate_all_expression_to_a_module(
                 ),
                 decorator_list=[],
                 body=block,
+                type_params=[],
             )
 
             module_node = ast.Module(body=[async_func_def_node], type_ignores=[])
@@ -925,6 +961,21 @@ def _execute_comprehension(
             )
 
             module_node = ast.Module(body=[func_def_node])
+        elif sys.version_info < (3, 12):
+            func_def_node = ast.FunctionDef(
+                name="generator_expr",
+                args=ast.arguments(
+                    args=args,
+                    posonlyargs=[],
+                    kwonlyargs=[],
+                    kw_defaults=[],
+                    defaults=[],
+                ),
+                decorator_list=[],
+                body=[ast.Return(node)],
+            )
+
+            module_node = ast.Module(body=[func_def_node], type_ignores=[])
         else:
             func_def_node = ast.FunctionDef(
                 name="generator_expr",
@@ -937,6 +988,7 @@ def _execute_comprehension(
                 ),
                 decorator_list=[],
                 body=[ast.Return(node)],
+                type_params=[],
             )
 
             module_node = ast.Module(body=[func_def_node], type_ignores=[])

precommit.py

@@ -99,8 +99,18 @@ def main() -> int:
             pylint_targets.append("tests_3_8")
             pylint_targets.append("tests_with_others")
 
+        import pylint
+        import packaging.version
+
+        if packaging.version.parse(pylint.__version__) < packaging.version.parse(
+            "3.3.7"
+        ):
+            rcfile = "pylint.lt_3.3.7.rc"
+        else:
+            rcfile = "pylint.ge_3.3.7.rc"
+
         subprocess.check_call(
-            ["pylint", "--rcfile=pylint.rc"] + pylint_targets, cwd=str(repo_root)
+            ["pylint", f"--rcfile={rcfile}"] + pylint_targets, cwd=str(repo_root)
         )
 
     print("Pydocstyle'ing...")

pylint.ge_3.3.7.rc

@@ -0,0 +1,9 @@
+[TYPECHECK]
+ignored-modules = numpy
+ignored-classes = numpy,PurePath
+
+[FORMAT]
+max-line-length=120
+
+[MESSAGES CONTROL]
+disable=too-few-public-methods,len-as-condition,duplicate-code,no-else-raise,too-many-locals,too-many-branches,too-many-lines,too-many-arguments,too-many-statements,too-many-nested-blocks,too-many-function-args,too-many-instance-attributes,too-many-public-methods,protected-access,consider-using-in,no-member,consider-using-f-string,use-dict-literal,redundant-keyword-arg,no-else-return,too-many-positional-arguments

pylint.rc pylint.lt_3.3.7.rcpylint.rc renamed to pylint.lt_3.3.7.rc

@@ -1,11 +1,9 @@
 [TYPECHECK]
 ignored-modules = numpy
 ignored-classes = numpy,PurePath
-generated-members=bottle\.request\.forms\.decode,bottle\.request\.query\.decode
 
 [FORMAT]
 max-line-length=120
 
 [MESSAGES CONTROL]
 disable=too-few-public-methods,len-as-condition,duplicate-code,no-else-raise,too-many-locals,too-many-branches,too-many-lines,too-many-arguments,too-many-statements,too-many-nested-blocks,too-many-function-args,too-many-instance-attributes,too-many-public-methods,protected-access,consider-using-in,no-member,consider-using-f-string,use-dict-literal,redundant-keyword-arg,no-else-return
-

setup.py

@@ -36,13 +36,13 @@
         # fmt: off
         'Development Status :: 5 - Production/Stable',
         'Intended Audience :: Developers',
-        'License :: OSI Approved :: MIT License',
         'Programming Language :: Python :: 3.6',
         'Programming Language :: Python :: 3.7',
         'Programming Language :: Python :: 3.8',
         'Programming Language :: Python :: 3.9',
         'Programming Language :: Python :: 3.10',
         'Programming Language :: Python :: 3.11',
+        'Programming Language :: Python :: 3.12',
         # fmt: on
     ],
     license="License :: OSI Approved :: MIT License",
@@ -55,7 +55,8 @@
     ],
     extras_require={
         "dev": [
-            'pylint==3.2.7;python_version>="3.8"',
+            'pylint==2.17.5;python_version>="3.7" and python_version<"3.12"',
+            'pylint==4.0.2;python_version>="3.12"',
             "tox>=3.0.0",
             "pydocstyle>=6.3.0,<7",
             "coverage>=6.5.0,<7",
@@ -67,8 +68,9 @@
             "typeguard>=2,<5",
             "astor==0.8.1",
             "numpy>=1,<2",
-            'mypy==1.14.1;python_version>="3.8"',
-            'black==24.8.0;python_version>="3.8"',
+            'mypy==1.5.1;python_version>="3.8" and python_version<"3.12"',
+            'mypy==1.18.2;python_version>="3.12"',
+            'black==23.9.1;python_version>="3.8"',
             'deal>=4,<5;python_version>="3.8"',
             'asyncstdlib==3.9.1;python_version>="3.8"',
         ]

tests/test_inheritance_postcondition.py

@@ -535,11 +535,16 @@ class B(A):
                 "Can't instantiate abstract class B with abstract methods func",
                 str(type_err),
             )
-        else:
+        elif sys.version_info < (3, 12):
             self.assertEqual(
                 "Can't instantiate abstract class B with abstract method func",
                 str(type_err),
             )
+        else:
+            self.assertEqual(
+                "Can't instantiate abstract class B without an implementation for abstract method 'func'",
+                str(type_err),
+            )
 
 
 if __name__ == "__main__":

tests/test_inheritance_precondition.py

@@ -587,11 +587,16 @@ class B(A):
                 "Can't instantiate abstract class B with abstract methods func",
                 str(type_err),
             )
-        else:
+        elif sys.version_info < (3, 12):
             self.assertEqual(
                 "Can't instantiate abstract class B with abstract method func",
                 str(type_err),
             )
+        else:
+            self.assertEqual(
+                "Can't instantiate abstract class B without an implementation for abstract method 'func'",
+                str(type_err),
+            )
 
     def test_cant_weaken_base_function_without_preconditions(self) -> None:
         class A(icontract.DBC):

tests_with_others/test_deal.py

@@ -1,7 +1,6 @@
 # pylint: disable=missing-docstring
 # pylint: disable=broad-except
 # pylint: disable=invalid-name
-
 import unittest
 from typing import Optional
 
@@ -10,7 +9,11 @@
 
 class TestDeal(unittest.TestCase):
     def test_recursion_handled_in_preconditions(self) -> None:
-        @deal.pre(lambda _: another_func())  # type: ignore
+        # NOTE (mristin):
+        # Mypy 1.5.1 throws here a misc error -- that the untyped decorator forces the function to be untyped as well.
+        # On the other hand, mypy 1.18.2 can figure this situation, and throws unused-ignore. We ignore both cases
+        # to be able to support both versions of mypy.
+        @deal.pre(lambda _: another_func())  # type: ignore[unused-ignore,misc]
         @deal.pre(lambda _: yet_another_func())
         def some_func() -> bool:
             return True