]> git.madduck.net Git - etc/vim.git/blob - src/black/cache.py

madduck's git repository

Every one of the projects in this repository is available at the canonical URL git://git.madduck.net/madduck/pub/<projectpath> — see each project's metadata for the exact URL.

All patches and comments are welcome. Please squash your changes to logical commits before using git-format-patch and git-send-email to patches@git.madduck.net. If you'd read over the Git project's submission guidelines and adhered to them, I'd be especially grateful.

SSH access, as well as push access can be individually arranged.

If you use my repositories frequently, consider adding the following snippet to ~/.gitconfig and using the third clone URL listed for each project:

[url "git://git.madduck.net/madduck/"]
  insteadOf = madduck:

Add passing 3.11 CI by exempting blackd tests (#3234)
[etc/vim.git] / src / black / cache.py
1 """Caching of formatted files with feature-based invalidation."""
2
3 import os
4 import pickle
5 import tempfile
6 from pathlib import Path
7 from typing import Dict, Iterable, Set, Tuple
8
9 from platformdirs import user_cache_dir
10
11 from _black_version import version as __version__
12 from black.mode import Mode
13
14 # types
15 Timestamp = float
16 FileSize = int
17 CacheInfo = Tuple[Timestamp, FileSize]
18 Cache = Dict[str, CacheInfo]
19
20
21 def get_cache_dir() -> Path:
22     """Get the cache directory used by black.
23
24     Users can customize this directory on all systems using `BLACK_CACHE_DIR`
25     environment variable. By default, the cache directory is the user cache directory
26     under the black application.
27
28     This result is immediately set to a constant `black.cache.CACHE_DIR` as to avoid
29     repeated calls.
30     """
31     # NOTE: Function mostly exists as a clean way to test getting the cache directory.
32     default_cache_dir = user_cache_dir("black", version=__version__)
33     cache_dir = Path(os.environ.get("BLACK_CACHE_DIR", default_cache_dir))
34     return cache_dir
35
36
37 CACHE_DIR = get_cache_dir()
38
39
40 def read_cache(mode: Mode) -> Cache:
41     """Read the cache if it exists and is well formed.
42
43     If it is not well formed, the call to write_cache later should resolve the issue.
44     """
45     cache_file = get_cache_file(mode)
46     if not cache_file.exists():
47         return {}
48
49     with cache_file.open("rb") as fobj:
50         try:
51             cache: Cache = pickle.load(fobj)
52         except (pickle.UnpicklingError, ValueError, IndexError):
53             return {}
54
55     return cache
56
57
58 def get_cache_file(mode: Mode) -> Path:
59     return CACHE_DIR / f"cache.{mode.get_cache_key()}.pickle"
60
61
62 def get_cache_info(path: Path) -> CacheInfo:
63     """Return the information used to check if a file is already formatted or not."""
64     stat = path.stat()
65     return stat.st_mtime, stat.st_size
66
67
68 def filter_cached(cache: Cache, sources: Iterable[Path]) -> Tuple[Set[Path], Set[Path]]:
69     """Split an iterable of paths in `sources` into two sets.
70
71     The first contains paths of files that modified on disk or are not in the
72     cache. The other contains paths to non-modified files.
73     """
74     todo, done = set(), set()
75     for src in sources:
76         res_src = src.resolve()
77         if cache.get(str(res_src)) != get_cache_info(res_src):
78             todo.add(src)
79         else:
80             done.add(src)
81     return todo, done
82
83
84 def write_cache(cache: Cache, sources: Iterable[Path], mode: Mode) -> None:
85     """Update the cache file."""
86     cache_file = get_cache_file(mode)
87     try:
88         CACHE_DIR.mkdir(parents=True, exist_ok=True)
89         new_cache = {
90             **cache,
91             **{str(src.resolve()): get_cache_info(src) for src in sources},
92         }
93         with tempfile.NamedTemporaryFile(dir=str(cache_file.parent), delete=False) as f:
94             pickle.dump(new_cache, f, protocol=4)
95         os.replace(f.name, cache_file)
96     except OSError:
97         pass