Make cache work with non-default line lenghts (#163)

diff --git a/README.md b/README.md
index e2f91effd32fed6093fc4c0f79057ce6bcaa0061..02cf2f92a7646af06ad284f8ef1e3690c5280383 100644 (file)
--- a/README.md
+++ b/README.md
@@ -458,9 +458,9 @@ location of the file depends on the black version and the system on which black
 is run. The file is non-portable. The standard location on common operating systems
 is:
 
-* Windows: `C:\\Users\<username>\AppData\Local\black\black\Cache\<version>\cache.pickle`
-* macOS: `/Users/<username>/Library/Caches/black/<version>/cache.pickle`
-* Linux: `/home/<username>/.cache/black/<version>/cache.pickle`
+* Windows: `C:\\Users\<username>\AppData\Local\black\black\Cache\<version>\cache.<line-length>.pickle`
+* macOS: `/Users/<username>/Library/Caches/black/<version>/cache.<line-length>.pickle`
+* Linux: `/home/<username>/.cache/black/<version>/cache.<line-length>.pickle`
 
 
 ## Testimonials

diff --git a/black.py b/black.py
index 11386d23f9df76ad9b57129ea2bb28eba4792f5d..aeb740226f3ee4461c7d7b81f361634d63835b07 100644 (file)
--- a/black.py
+++ b/black.py
@@ -233,7 +233,7 @@ def reformat_one(
         else:
             cache: Cache = {}
             if write_back != WriteBack.DIFF:
-                cache = read_cache()
+                cache = read_cache(line_length)
                 src = src.resolve()
                 if src in cache and cache[src] == get_cache_info(src):
                     changed = Changed.CACHED
@@ -245,7 +245,7 @@ def reformat_one(
             ):
                 changed = Changed.YES
             if write_back != WriteBack.DIFF and changed is not Changed.NO:
-                write_cache(cache, [src])
+                write_cache(cache, [src], line_length)
         report.done(src, changed)
     except Exception as exc:
         report.failed(src, str(exc))
@@ -269,7 +269,7 @@ async def schedule_formatting(
     """
     cache: Cache = {}
     if write_back != WriteBack.DIFF:
-        cache = read_cache()
+        cache = read_cache(line_length)
         sources, cached = filter_cached(cache, sources)
         for src in cached:
             report.done(src, Changed.CACHED)
@@ -312,7 +312,7 @@ async def schedule_formatting(
     if cancelled:
         await asyncio.gather(*cancelled, loop=loop, return_exceptions=True)
     if write_back != WriteBack.DIFF and formatted:
-        write_cache(cache, formatted)
+        write_cache(cache, formatted, line_length)
 
 
 def format_file_in_place(
@@ -2473,18 +2473,22 @@ def sub_twice(regex: Pattern[str], replacement: str, original: str) -> str:
 
 
 CACHE_DIR = Path(user_cache_dir("black", version=__version__))
-CACHE_FILE = CACHE_DIR / "cache.pickle"
 
 
-def read_cache() -> Cache:
+def get_cache_file(line_length: int) -> Path:
+    return CACHE_DIR / f"cache.{line_length}.pickle"
+
+
+def read_cache(line_length: int) -> Cache:
     """Read the cache if it exists and is well formed.
 
     If it is not well formed, the call to write_cache later should resolve the issue.
     """
-    if not CACHE_FILE.exists():
+    cache_file = get_cache_file(line_length)
+    if not cache_file.exists():
         return {}
 
-    with CACHE_FILE.open("rb") as fobj:
+    with cache_file.open("rb") as fobj:
         try:
             cache: Cache = pickle.load(fobj)
         except pickle.UnpicklingError:
@@ -2517,13 +2521,14 @@ def filter_cached(
     return todo, done
 
 
-def write_cache(cache: Cache, sources: List[Path]) -> None:
+def write_cache(cache: Cache, sources: List[Path], line_length: int) -> None:
     """Update the cache file."""
+    cache_file = get_cache_file(line_length)
     try:
         if not CACHE_DIR.exists():
             CACHE_DIR.mkdir(parents=True)
         new_cache = {**cache, **{src.resolve(): get_cache_info(src) for src in sources}}
-        with CACHE_FILE.open("wb") as fobj:
+        with cache_file.open("wb") as fobj:
             pickle.dump(new_cache, fobj, protocol=pickle.HIGHEST_PROTOCOL)
     except OSError:
         pass

diff --git a/tests/test_black.py b/tests/test_black.py
index dd3beed99abe0e5b6d7b3f37188fa41420f38493..94cbe35da391aca617be1dbde47a98cd797a4a9f 100644 (file)
--- a/tests/test_black.py
+++ b/tests/test_black.py
@@ -57,8 +57,7 @@ def cache_dir(exists: bool = True) -> Iterator[Path]:
         cache_dir = Path(workspace)
         if not exists:
             cache_dir = cache_dir / "new"
-        cache_file = cache_dir / "cache.pkl"
-        with patch("black.CACHE_DIR", cache_dir), patch("black.CACHE_FILE", cache_file):
+        with patch("black.CACHE_DIR", cache_dir):
             yield cache_dir
 
 
@@ -492,15 +491,16 @@ class BlackTestCase(unittest.TestCase):
 
     def test_cache_broken_file(self) -> None:
         with cache_dir() as workspace:
-            with black.CACHE_FILE.open("w") as fobj:
+            cache_file = black.get_cache_file(black.DEFAULT_LINE_LENGTH)
+            with cache_file.open("w") as fobj:
                 fobj.write("this is not a pickle")
-            self.assertEqual(black.read_cache(), {})
+            self.assertEqual(black.read_cache(black.DEFAULT_LINE_LENGTH), {})
             src = (workspace / "test.py").resolve()
             with src.open("w") as fobj:
                 fobj.write("print('hello')")
             result = CliRunner().invoke(black.main, [str(src)])
             self.assertEqual(result.exit_code, 0)
-            cache = black.read_cache()
+            cache = black.read_cache(black.DEFAULT_LINE_LENGTH)
             self.assertIn(src, cache)
 
     def test_cache_single_file_already_cached(self) -> None:
@@ -508,7 +508,7 @@ class BlackTestCase(unittest.TestCase):
             src = (workspace / "test.py").resolve()
             with src.open("w") as fobj:
                 fobj.write("print('hello')")
-            black.write_cache({}, [src])
+            black.write_cache({}, [src], black.DEFAULT_LINE_LENGTH)
             result = CliRunner().invoke(black.main, [str(src)])
             self.assertEqual(result.exit_code, 0)
             with src.open("r") as fobj:
@@ -525,14 +525,14 @@ class BlackTestCase(unittest.TestCase):
             two = (workspace / "two.py").resolve()
             with two.open("w") as fobj:
                 fobj.write("print('hello')")
-            black.write_cache({}, [one])
+            black.write_cache({}, [one], black.DEFAULT_LINE_LENGTH)
             result = CliRunner().invoke(black.main, [str(workspace)])
             self.assertEqual(result.exit_code, 0)
             with one.open("r") as fobj:
                 self.assertEqual(fobj.read(), "print('hello')")
             with two.open("r") as fobj:
                 self.assertEqual(fobj.read(), 'print("hello")\n')
-            cache = black.read_cache()
+            cache = black.read_cache(black.DEFAULT_LINE_LENGTH)
             self.assertIn(one, cache)
             self.assertIn(two, cache)
 
@@ -543,24 +543,26 @@ class BlackTestCase(unittest.TestCase):
                 fobj.write("print('hello')")
             result = CliRunner().invoke(black.main, [str(src), "--diff"])
             self.assertEqual(result.exit_code, 0)
-            self.assertFalse(black.CACHE_FILE.exists())
+            cache_file = black.get_cache_file(black.DEFAULT_LINE_LENGTH)
+            self.assertFalse(cache_file.exists())
 
     def test_no_cache_when_stdin(self) -> None:
         with cache_dir():
             result = CliRunner().invoke(black.main, ["-"], input="print('hello')")
             self.assertEqual(result.exit_code, 0)
-            self.assertFalse(black.CACHE_FILE.exists())
+            cache_file = black.get_cache_file(black.DEFAULT_LINE_LENGTH)
+            self.assertFalse(cache_file.exists())
 
     def test_read_cache_no_cachefile(self) -> None:
         with cache_dir():
-            self.assertEqual(black.read_cache(), {})
+            self.assertEqual(black.read_cache(black.DEFAULT_LINE_LENGTH), {})
 
     def test_write_cache_read_cache(self) -> None:
         with cache_dir() as workspace:
             src = (workspace / "test.py").resolve()
             src.touch()
-            black.write_cache({}, [src])
-            cache = black.read_cache()
+            black.write_cache({}, [src], black.DEFAULT_LINE_LENGTH)
+            cache = black.read_cache(black.DEFAULT_LINE_LENGTH)
             self.assertIn(src, cache)
             self.assertEqual(cache[src], black.get_cache_info(src))
 
@@ -583,7 +585,7 @@ class BlackTestCase(unittest.TestCase):
     def test_write_cache_creates_directory_if_needed(self) -> None:
         with cache_dir(exists=False) as workspace:
             self.assertFalse(workspace.exists())
-            black.write_cache({}, [])
+            black.write_cache({}, [], black.DEFAULT_LINE_LENGTH)
             self.assertTrue(workspace.exists())
 
     @event_loop(close=False)
@@ -599,14 +601,14 @@ class BlackTestCase(unittest.TestCase):
                 fobj.write('print("hello")\n')
             result = CliRunner().invoke(black.main, [str(workspace)])
             self.assertEqual(result.exit_code, 123)
-            cache = black.read_cache()
+            cache = black.read_cache(black.DEFAULT_LINE_LENGTH)
             self.assertNotIn(failing, cache)
             self.assertIn(clean, cache)
 
     def test_write_cache_write_fail(self) -> None:
         with cache_dir(), patch.object(Path, "open") as mock:
             mock.side_effect = OSError
-            black.write_cache({}, [])
+            black.write_cache({}, [], black.DEFAULT_LINE_LENGTH)
 
     def test_check_diff_use_together(self) -> None:
         with cache_dir():
@@ -626,6 +628,16 @@ class BlackTestCase(unittest.TestCase):
             )
             self.assertEqual(result.exit_code, 1)
 
+    def test_read_cache_line_lengths(self) -> None:
+        with cache_dir() as workspace:
+            path = (workspace / "file.py").resolve()
+            path.touch()
+            black.write_cache({}, [path], 1)
+            one = black.read_cache(1)
+            self.assertIn(path, one)
+            two = black.read_cache(2)
+            self.assertNotIn(path, two)
+
 
 if __name__ == "__main__":
     unittest.main()