Drop black dependency

CHANGES.rst

@@ -21,6 +21,8 @@ Added
   other formatters in the future. There's also a dummy ``none`` formatter plugin.
 - ``--formatter=none`` now skips running Black. This is useful when you only want to run
   Isort or Flynt_.
+- Black_ is no longer installed by default. Use ``pip install 'darker[black]'`` to get
+  Black support.
 
 Removed
 -------

README.rst

@@ -133,11 +133,11 @@ How?
 
 To install or upgrade, use::
 
-  pip install --upgrade darker~=2.1.1
+  pip install --upgrade darker[black]~=2.1.1
 
 Or, if you're using Conda_ for package management::
 
-  conda install -c conda-forge darker~=2.1.1 isort
+  conda install -c conda-forge darker~=2.1.1 black isort
   conda update -c conda-forge darker
 
 ..
@@ -146,6 +146,8 @@ Or, if you're using Conda_ for package management::
     specifier for Darker. See `Guarding against Black compatibility breakage`_ for more
     information.
 
+*New in version 3.0.0:* Black is no longer installed by default.
+
 The ``darker <myfile.py>`` or ``darker <directory>`` command
 reads the original file(s),
 formats them using Black_,
@@ -478,7 +480,7 @@ PyCharm/IntelliJ IDEA
 
 1. Install ``darker``::
 
-     $ pip install darker
+     $ pip install 'darker[black]'
 
 2. Locate your ``darker`` installation folder.
 
@@ -540,7 +542,7 @@ Visual Studio Code
 
 1. Install ``darker``::
 
-     $ pip install darker
+     $ pip install 'darker[black]'
 
 2. Locate your ``darker`` installation folder.
 
@@ -683,16 +685,20 @@ other reformatter tools you use to known compatible versions, for example:
 Using arguments
 ---------------
 
-You can provide arguments, such as enabling isort, by specifying ``args``.
-Note the inclusion of the isort Python package under ``additional_dependencies``:
+You can provide arguments, such as disabling Darker or enabling isort,
+by specifying ``args``.
+Note the absence of Black and the inclusion of the isort Python package
+under ``additional_dependencies``:
 
 .. code-block:: yaml
 
    - repo: https://github.com/akaihola/darker
      rev: v2.1.1
      hooks:
        - id: darker
-         args: [--isort]
+         args:
+           - --formatter=none
+           - --isort
          additional_dependencies:
            - isort~=5.9
 
@@ -779,6 +785,9 @@ The ``lint:`` option.
 Removed the ``lint:`` option and moved it into the GitHub action
 of the Graylint_ package.
 
+*New in version 3.0.0:*
+Black is now explicitly installed when running the action.
+
 
 Syntax highlighting
 ===================

action/main.py

@@ -22,7 +22,7 @@
 
 run([sys.executable, "-m", "venv", str(ENV_PATH)], check=True)  # nosec
 
-req = ["darker[color,isort]"]
+req = ["darker[black,color,isort]"]
 if VERSION:
     if VERSION.startswith("@"):
         req[0] = f"git+https://github.com/akaihola/darker{VERSION}#egg={req[0]}"

action/tests/test_main.py

@@ -91,23 +91,25 @@ def test_creates_virtualenv(tmp_path, main_patch):
 
 
 @pytest.mark.kwparametrize(
-    dict(run_main_env={}, expect=["darker[color,isort]"]),
+    dict(run_main_env={}, expect=["darker[black,color,isort]"]),
     dict(
-        run_main_env={"INPUT_VERSION": "1.5.0"}, expect=["darker[color,isort]==1.5.0"]
+        run_main_env={"INPUT_VERSION": "1.5.0"},
+        expect=["darker[black,color,isort]==1.5.0"],
     ),
     dict(
         run_main_env={"INPUT_VERSION": "@master"},
         expect=[
-            "git+https://github.com/akaihola/darker@master#egg=darker[color,isort]"
+            "git+https://github.com/akaihola/darker"
+            "@master#egg=darker[black,color,isort]"
         ],
     ),
     dict(
         run_main_env={"INPUT_LINT": "dummy"},
-        expect=["darker[color,isort]"],
+        expect=["darker[black,color,isort]"],
     ),
     dict(
         run_main_env={"INPUT_LINT": "dummy,foobar"},
-        expect=["darker[color,isort]"],
+        expect=["darker[black,color,isort]"],
     ),
 )
 def test_installs_packages(tmp_path, main_patch, run_main_env, expect):
@@ -208,15 +210,15 @@ def test_error_if_pip_fails(tmp_path, capsys):
         run_module("main")
 
     assert main_patch.subprocess.run.call_args_list[-1] == call(
-        [ANY, "-m", "pip", "install", "darker[color,isort]"],
+        [ANY, "-m", "pip", "install", "darker[black,color,isort]"],
         check=False,
         stdout=PIPE,
         stderr=STDOUT,
         encoding="utf-8",
     )
     assert (
         capsys.readouterr().out.splitlines()[-1]
-        == "::error::Failed to install darker[color,isort]."
+        == "::error::Failed to install darker[black,color,isort]."
     )
     main_patch.sys.exit.assert_called_once_with(42)
 

setup.cfg

@@ -28,7 +28,6 @@ package_dir =
 packages = find:
 install_requires =
     # NOTE: remember to keep `constraints-oldest.txt` in sync with these
-    black>=22.3.0
     darkgraylib~=2.1.0
     toml>=0.10.0
     typing_extensions>=4.0.1
@@ -52,6 +51,8 @@ console_scripts =
     darker = darker.__main__:main_with_error_handling
 
 [options.extras_require]
+black =
+    black>=22.3.0
 flynt =
     flynt>=0.76
 isort =

src/darker/command_line.py

@@ -5,8 +5,6 @@
 from functools import partial
 from typing import List, Optional, Tuple
 
-from black import TargetVersion
-
 import darkgraylib.command_line
 from darker import help as hlp
 from darker.config import (
@@ -15,6 +13,7 @@
     DarkerConfig,
     OutputMode,
 )
+from darker.configuration.target_version import TargetVersion
 from darker.formatters import get_formatter_names
 from darker.version import __version__
 from darkgraylib.command_line import add_parser_argument

src/darker/configuration/__init__.py

@@ -0,0 +1 @@
+"""Configuration and command line handling."""

src/darker/configuration/target_version.py

@@ -0,0 +1,19 @@
+"""Data structures configuring Darker and formatter plugin behavior."""
+
+from enum import Enum
+
+
+class TargetVersion(Enum):
+    """Python version numbers."""
+
+    PY33 = 3
+    PY34 = 4
+    PY35 = 5
+    PY36 = 6
+    PY37 = 7
+    PY38 = 8
+    PY39 = 9
+    PY310 = 10
+    PY311 = 11
+    PY312 = 12
+    PY313 = 13

src/darker/files.py

@@ -2,18 +2,9 @@
 
 from __future__ import annotations
 
-import inspect
-from typing import TYPE_CHECKING, Collection
-
-from black import (
-    DEFAULT_EXCLUDES,
-    DEFAULT_INCLUDES,
-    Report,
-    err,
-    find_user_pyproject_toml,
-    gen_python_files,
-    re_compile_maybe_verbose,
-)
+import re
+from functools import lru_cache
+from typing import TYPE_CHECKING, Collection, Iterable, Iterator, Pattern
 
 from darkgraylib.files import find_project_root
 
@@ -25,22 +16,116 @@
 
 def find_pyproject_toml(path_search_start: tuple[str, ...]) -> str | None:
     """Find the absolute filepath to a pyproject.toml if it exists"""
+
     path_project_root = find_project_root(path_search_start)
     path_pyproject_toml = path_project_root / "pyproject.toml"
     if path_pyproject_toml.is_file():
         return str(path_pyproject_toml)
+    return None
+
+
+DEFAULT_EXCLUDE_RE = re.compile(
+    r"/(\.direnv"
+    r"|\.eggs"
+    r"|\.git"
+    r"|\.hg"
+    r"|\.ipynb_checkpoints"
+    r"|\.mypy_cache"
+    r"|\.nox"
+    r"|\.pytest_cache"
+    r"|\.ruff_cache"
+    r"|\.tox"
+    r"|\.svn"
+    r"|\.venv"
+    r"|\.vscode"
+    r"|__pypackages__"
+    r"|_build"
+    r"|buck-out"
+    r"|build"
+    r"|dist"
+    r"|venv)/"
+)
+DEFAULT_INCLUDE_RE = re.compile(r"(\.pyi?|\.ipynb)$")
+
+
+@lru_cache
+def _cached_resolve(path: Path) -> Path:
+    return path.resolve()
+
 
+def _resolves_outside_root_or_cannot_stat(path: Path, root: Path) -> bool:
+    """Return whether path is a symlink that points outside the root directory.
+
+    Also returns True if we failed to resolve the path.
+
+    This function has been adapted from Black 24.10.0.
+
+    """
     try:
-        path_user_pyproject_toml = find_user_pyproject_toml()
-        return (
-            str(path_user_pyproject_toml)
-            if path_user_pyproject_toml.is_file()
-            else None
-        )
-    except (PermissionError, RuntimeError) as e:
-        # We do not have access to the user-level config directory, so ignore it.
-        err(f"Ignoring user configuration directory due to {e!r}")
-        return None
+        resolved_path = _cached_resolve(path)
+    except OSError:
+        return True
+    try:
+        resolved_path.relative_to(root)
+    except ValueError:
+        return True
+    return False
+
+
+def _path_is_excluded(
+    normalized_path: str,
+    pattern: Pattern[str] | None,
+) -> bool:
+    """Return whether the path is excluded by the pattern.
+
+    This function has been adapted from Black 24.10.0.
+
+    """
+    match = pattern.search(normalized_path) if pattern else None
+    return bool(match and match.group(0))
+
+
+def _gen_python_files(
+    paths: Iterable[Path],
+    root: Path,
+    exclude: Pattern[str],
+    extend_exclude: Pattern[str] | None,
+    force_exclude: Pattern[str] | None,
+) -> Iterator[Path]:
+    """Generate all files under ``path`` whose paths are not excluded.
+
+    This function has been adapted from Black 24.10.0.
+
+    """
+    if not root.is_absolute():
+        message = f"`root` must be absolute, not {root}"
+        raise ValueError(message)
+    for child in paths:
+        if not child.is_absolute():
+            message = f"`child` must be absolute, not {child}"
+            raise ValueError(message)
+        root_relative_path = child.relative_to(root).as_posix()
+
+        # Then ignore with `--exclude` `--extend-exclude` and `--force-exclude` options.
+        root_relative_path = f"/{root_relative_path}"
+        if child.is_dir():
+            root_relative_path = f"{root_relative_path}/"
+
+        if any(
+            _path_is_excluded(root_relative_path, x)
+            for x in [exclude, extend_exclude, force_exclude]
+        ) or _resolves_outside_root_or_cannot_stat(child, root):
+            continue
+
+        if child.is_dir():
+            yield from _gen_python_files(
+                child.iterdir(), root, exclude, extend_exclude, force_exclude
+            )
+
+        elif child.is_file():
+            include_match = DEFAULT_INCLUDE_RE.search(root_relative_path)
+            if include_match:
+                yield child
 
 
 def filter_python_files(
@@ -58,32 +143,16 @@ def filter_python_files(
              ``black_config``, relative to ``root``.
 
     """
-    sig = inspect.signature(gen_python_files)
-    # those two exist and are required in black>=21.7b1.dev9
-    kwargs = {"verbose": False, "quiet": False} if "verbose" in sig.parameters else {}
-    # `gitignore=` was replaced with `gitignore_dict=` in black==22.10.1.dev19+gffaaf48
-    for param in sig.parameters:
-        if param == "gitignore":
-            kwargs[param] = None  # type: ignore[assignment]
-        elif param == "gitignore_dict":
-            kwargs[param] = {}  # type: ignore[assignment]
     absolute_paths = {p.resolve() for p in paths}
     directories = {p for p in absolute_paths if p.is_dir()}
     files = {p for p in absolute_paths if p not in directories}
     files_from_directories = set(
-        gen_python_files(
+        _gen_python_files(
             directories,
             root,
-            include=DEFAULT_INCLUDE_RE,
-            exclude=formatter.get_exclude(DEFAULT_EXCLUDE_RE),
-            extend_exclude=formatter.get_extend_exclude(),
-            force_exclude=formatter.get_force_exclude(),
-            report=Report(),
-            **kwargs,  # type: ignore[arg-type]
+            formatter.get_exclude(DEFAULT_EXCLUDE_RE),
+            formatter.get_extend_exclude(),
+            formatter.get_force_exclude(),
         )
     )
     return {p.resolve().relative_to(root) for p in files_from_directories | files}
-
-
-DEFAULT_EXCLUDE_RE = re_compile_maybe_verbose(DEFAULT_EXCLUDES)
-DEFAULT_INCLUDE_RE = re_compile_maybe_verbose(DEFAULT_INCLUDES)