refactor: drop support for Python 3.7 (copier-org#1252)

.github/workflows/ci.yml

@@ -32,7 +32,7 @@ jobs:
           - macos-latest
           - ubuntu-latest
           - windows-latest
-        python-version: ["3.7", "3.8", "3.9", "3.10", "3.11"]
+        python-version: ["3.8", "3.9", "3.10", "3.11"]
     runs-on: ${{ matrix.os }}
     steps:
       # HACK https://github.com/actions/cache/issues/315

README.md

@@ -21,7 +21,7 @@ A library and CLI app for rendering project templates.
 
 ## Installation
 
-1. Install Python 3.7 or newer (3.8 or newer if you're on Windows).
+1. Install Python 3.8 or newer.
 1. Install Git 2.27 or newer.
 1. To use as a CLI app: `pipx install copier`
 1. To use as a library: `pip install copier` or `conda install -c conda-forge copier`

copier/main.py

@@ -7,11 +7,22 @@
 from contextlib import suppress
 from dataclasses import asdict, field, replace
 from filecmp import dircmp
-from functools import partial
+from functools import cached_property, partial
 from itertools import chain
 from pathlib import Path
 from shutil import rmtree
-from typing import Callable, Iterable, Mapping, Optional, Sequence, Set, Union
+from tempfile import TemporaryDirectory
+from typing import (
+    Callable,
+    Iterable,
+    Literal,
+    Mapping,
+    Optional,
+    Sequence,
+    Set,
+    Union,
+    get_args,
+)
 from unicodedata import normalize
 
 from jinja2.loaders import FileSystemLoader
@@ -34,45 +45,18 @@
 )
 from .subproject import Subproject
 from .template import Task, Template
-from .tools import OS, Style, TemporaryDirectory, printf, readlink
+from .tools import OS, Style, printf, readlink
 from .types import (
     MISSING,
     AnyByStrDict,
     JSONSerializable,
-    Literal,
     OptStr,
     RelativePath,
     StrOrPath,
     StrSeq,
 )
 from .user_data import DEFAULT_DATA, AnswersMap, Question
 
-# HACK https://github.com/python/mypy/issues/8520#issuecomment-772081075
-if sys.version_info >= (3, 8):
-    from functools import cached_property
-else:
-    from backports.cached_property import cached_property
-
-# Backport of `shutil.copytree` for python 3.7 to accept `dirs_exist_ok` argument
-if sys.version_info >= (3, 8):
-    from shutil import copytree
-else:
-    from distutils.dir_util import copy_tree
-
-    def copytree(src: Path, dst: Path, dirs_exist_ok: bool = False):
-        """Backport of `shutil.copytree` with `dirs_exist_ok` argument.
-
-        Can be remove once python 3.7 dropped.
-        """
-        copy_tree(str(src), str(dst))
-
-
-# HACK https://github.com/python/mypy/issues/8520#issuecomment-772081075
-if sys.version_info >= (3, 8):
-    from typing import get_args
-else:
-    from typing_extensions import get_args
-
 
 @dataclass(config=ConfigDict(extra="forbid"))
 class Worker:

copier/subproject.py

@@ -3,7 +3,7 @@
 A *subproject* is a project that gets rendered and/or updated with Copier.
 """
 
-import sys
+from functools import cached_property
 from pathlib import Path
 from typing import Optional
 
@@ -16,12 +16,6 @@
 from .types import AbsolutePath, AnyByStrDict, VCSTypes
 from .vcs import is_in_git_repo
 
-# HACK https://github.com/python/mypy/issues/8520#issuecomment-772081075
-if sys.version_info >= (3, 8):
-    from functools import cached_property
-else:
-    from backports.cached_property import cached_property
-
 
 @dataclass
 class Subproject:

copier/template.py

@@ -1,12 +1,12 @@
 """Tools related to template management."""
 import re
-import sys
 from collections import ChainMap, defaultdict
 from contextlib import suppress
 from dataclasses import field
+from functools import cached_property
 from pathlib import Path
 from shutil import rmtree
-from typing import List, Mapping, Optional, Sequence, Set, Tuple
+from typing import List, Literal, Mapping, Optional, Sequence, Set, Tuple
 from warnings import warn
 
 import dunamai
@@ -30,14 +30,6 @@
 from .types import AnyByStrDict, Env, OptStr, StrSeq, Union, VCSTypes
 from .vcs import checkout_latest_tag, clone, get_repo
 
-# HACK https://github.com/python/mypy/issues/8520#issuecomment-772081075
-if sys.version_info >= (3, 8):
-    from functools import cached_property
-else:
-    from backports.cached_property import cached_property
-
-from .types import Literal
-
 # Default list of files in the template to exclude from the rendered project
 DEFAULT_EXCLUDE: Tuple[str, ...] = (
     "copier.yaml",

copier/tools.py

@@ -3,27 +3,19 @@
 import errno
 import os
 import platform
-import shutil
 import stat
 import sys
-import tempfile
-import warnings
 from contextlib import suppress
+from importlib.metadata import version
 from pathlib import Path
 from types import TracebackType
-from typing import Any, Callable, Optional, TextIO, Tuple, Union, cast
+from typing import Any, Callable, Literal, Optional, TextIO, Tuple, Union, cast
 
 import colorama
 from packaging.version import Version
 from pydantic import StrictBool
 
-from .types import IntSeq, Literal
-
-# TODO Remove condition when dropping python 3.8 support
-if sys.version_info < (3, 8):
-    from importlib_metadata import version
-else:
-    from importlib.metadata import version
+from .types import IntSeq
 
 colorama.init()
 
@@ -142,7 +134,8 @@ def handle_remove_readonly(
 ) -> None:
     """Handle errors when trying to remove read-only files through `shutil.rmtree`.
 
-    This handler makes sure the given file is writable, then re-execute the given removal function.
+    On Windows, `shutil.rmtree` does not handle read-only files very well. This handler
+    makes sure the given file is writable, then re-execute the given removal function.
 
     Arguments:
         func: An OS-dependant function used to remove a file.
@@ -157,41 +150,12 @@ def handle_remove_readonly(
         raise
 
 
-# See https://github.com/copier-org/copier/issues/345
-class TemporaryDirectory(tempfile.TemporaryDirectory):
-    """A custom version of `tempfile.TemporaryDirectory` that handles read-only files better.
-
-    On Windows, before Python 3.8, `shutil.rmtree` does not handle read-only files very well.
-    This custom class makes use of a [special error handler][copier.tools.handle_remove_readonly]
-    to make sure that a temporary directory containing read-only files (typically created
-    when git-cloning a repository) is properly cleaned-up (i.e. removed) after using it
-    in a context manager.
-    """
-
-    @classmethod
-    def _cleanup(cls, name, warn_message):
-        cls._robust_cleanup(name)
-        warnings.warn(warn_message, ResourceWarning)
-
-    def cleanup(self):
-        """Remove directory safely."""
-        if self._finalizer.detach():
-            self._robust_cleanup(self.name)
-
-    @staticmethod
-    def _robust_cleanup(name):
-        shutil.rmtree(name, ignore_errors=False, onerror=handle_remove_readonly)
-
-
 def readlink(link: Path) -> Path:
     """A custom version of os.readlink/pathlib.Path.readlink.
 
     pathlib.Path.readlink is what we ideally would want to use, but it is only available on python>=3.9.
-    os.readlink doesn't support Path and bytes on Windows for python<3.8
     """
     if sys.version_info >= (3, 9):
         return link.readlink()
-    elif sys.version_info >= (3, 8) or os.name != "nt":
-        return Path(os.readlink(link))
     else:
-        return Path(os.readlink(str(link)))
+        return Path(os.readlink(link))

copier/types.py

@@ -2,16 +2,20 @@
 
 import sys
 from pathlib import Path
-from typing import Any, Dict, Mapping, NewType, Optional, Sequence, TypeVar, Union
+from typing import (
+    Any,
+    Dict,
+    Literal,
+    Mapping,
+    NewType,
+    Optional,
+    Sequence,
+    TypeVar,
+    Union,
+)
 
 from pydantic import AfterValidator
 
-# HACK https://github.com/python/mypy/issues/8520#issuecomment-772081075
-if sys.version_info >= (3, 8):
-    from typing import Literal
-else:
-    from typing_extensions import Literal
-
 if sys.version_info >= (3, 9):
     from typing import Annotated
 else:

copier/user_data.py

@@ -1,24 +1,14 @@
 """Functions used to load user data."""
 import json
-import sys
 import warnings
 from collections import ChainMap
 from dataclasses import field
 from datetime import datetime
+from functools import cached_property
 from hashlib import sha512
 from os import urandom
 from pathlib import Path
-from typing import (
-    TYPE_CHECKING,
-    Any,
-    Callable,
-    Dict,
-    Mapping,
-    Optional,
-    Sequence,
-    Set,
-    Union,
-)
+from typing import Any, Callable, Dict, Mapping, Optional, Sequence, Set, Union
 
 import yaml
 from jinja2 import UndefinedError
@@ -35,15 +25,6 @@
 from .tools import cast_str_to_bool, force_str_end
 from .types import MISSING, AnyByStrDict, MissingType, OptStr, OptStrOrPath, StrOrPath
 
-# HACK https://github.com/python/mypy/issues/8520#issuecomment-772081075
-if sys.version_info >= (3, 8):
-    from functools import cached_property
-else:
-    from backports.cached_property import cached_property
-
-if TYPE_CHECKING:
-    pass
-
 
 # TODO Remove these two functions as well as DEFAULT_DATA in a future release
 def _now():

copier/vcs.py

@@ -4,7 +4,7 @@
 import sys
 from contextlib import suppress
 from pathlib import Path
-from tempfile import mkdtemp
+from tempfile import TemporaryDirectory, mkdtemp
 from warnings import warn
 
 from packaging import version
@@ -13,7 +13,6 @@
 from plumbum.cmd import git
 
 from .errors import DirtyLocalWarning, ShallowCloneWarning
-from .tools import TemporaryDirectory
 from .types import OptBool, OptStr, StrOrPath
 
 GIT_PREFIX = ("git@", "git://", "git+", "https://github.com/", "https://gitlab.com/")