X-Git-Url: https://git.madduck.net/etc/vim.git/blobdiff_plain/69ca0a4c7a365c5f5eea519a90980bab72cab764..8e618f386995fa89434834e6a793a1057e58112a:/tests/test_black.py

diff --git a/tests/test_black.py b/tests/test_black.py
index e5e1777..dee6ead 100644
--- a/tests/test_black.py
+++ b/tests/test_black.py
@@ -104,6 +104,7 @@ class FakeContext(click.Context):
 
     def __init__(self) -> None:
         self.default_map: Dict[str, Any] = {}
+        self.params: Dict[str, Any] = {}
         # Dummy root, since most of the tests don't care about it
         self.obj: Dict[str, Any] = {"root": PROJECT_ROOT}
 
@@ -148,8 +149,7 @@ class BlackTestCase(BlackBaseTestCase):
         tmp_file = Path(black.dump_to_file())
         try:
             self.assertFalse(ff(tmp_file, write_back=black.WriteBack.YES))
-            with open(tmp_file, encoding="utf8") as f:
-                actual = f.read()
+            actual = tmp_file.read_text(encoding="utf-8")
         finally:
             os.unlink(tmp_file)
         self.assertFormatEqual(expected, actual)
@@ -177,7 +177,7 @@ class BlackTestCase(BlackBaseTestCase):
                     ff(tmp_file, mode=mode, write_back=black.WriteBack.YES)
                 )
                 with open(tmp_file, "rb") as f:
-                    actual = f.read().decode("utf8")
+                    actual = f.read().decode("utf-8")
             finally:
                 os.unlink(tmp_file)
             self.assertFormatEqual(expected, actual)
@@ -197,7 +197,7 @@ class BlackTestCase(BlackBaseTestCase):
                 f"--line-length={black.DEFAULT_LINE_LENGTH}",
                 f"--config={EMPTY_CONFIG}",
             ],
-            input=BytesIO(source.encode("utf8")),
+            input=BytesIO(source.encode("utf-8")),
         )
         self.assertEqual(result.exit_code, 0)
         self.assertFormatEqual(expected, result.output)
@@ -207,8 +207,8 @@ class BlackTestCase(BlackBaseTestCase):
 
     def test_piping_diff(self) -> None:
         diff_header = re.compile(
-            r"(STDIN|STDOUT)\t\d\d\d\d-\d\d-\d\d \d\d:\d\d:\d\d\.\d\d\d\d\d\d "
-            r"\+\d\d\d\d"
+            r"(STDIN|STDOUT)\t\d\d\d\d-\d\d-\d\d \d\d:\d\d:\d\d\.\d\d\d\d\d\d"
+            r"\+\d\d:\d\d"
         )
         source, _ = read_data("simple_cases", "expression.py")
         expected, _ = read_data("simple_cases", "expression.diff")
@@ -220,7 +220,7 @@ class BlackTestCase(BlackBaseTestCase):
             f"--config={EMPTY_CONFIG}",
         ]
         result = BlackRunner().invoke(
-            black.main, args, input=BytesIO(source.encode("utf8"))
+            black.main, args, input=BytesIO(source.encode("utf-8"))
         )
         self.assertEqual(result.exit_code, 0)
         actual = diff_header.sub(DETERMINISTIC_HEADER, result.output)
@@ -238,7 +238,7 @@ class BlackTestCase(BlackBaseTestCase):
             f"--config={EMPTY_CONFIG}",
         ]
         result = BlackRunner().invoke(
-            black.main, args, input=BytesIO(source.encode("utf8"))
+            black.main, args, input=BytesIO(source.encode("utf-8"))
         )
         actual = result.output
         # Again, the contents are checked in a different test, so only look for colors.
@@ -271,13 +271,21 @@ class BlackTestCase(BlackBaseTestCase):
         versions = black.detect_target_versions(root)
         self.assertIn(black.TargetVersion.PY38, versions)
 
+    def test_pep_695_version_detection(self) -> None:
+        for file in ("type_aliases", "type_params"):
+            source, _ = read_data("py_312", file)
+            root = black.lib2to3_parse(source)
+            features = black.get_features_used(root)
+            self.assertIn(black.Feature.TYPE_PARAMS, features)
+            versions = black.detect_target_versions(root)
+            self.assertIn(black.TargetVersion.PY312, versions)
+
     def test_expression_ff(self) -> None:
         source, expected = read_data("simple_cases", "expression.py")
         tmp_file = Path(black.dump_to_file(source))
         try:
             self.assertTrue(ff(tmp_file, write_back=black.WriteBack.YES))
-            with open(tmp_file, encoding="utf8") as f:
-                actual = f.read()
+            actual = tmp_file.read_text(encoding="utf-8")
         finally:
             os.unlink(tmp_file)
         self.assertFormatEqual(expected, actual)
@@ -291,7 +299,7 @@ class BlackTestCase(BlackBaseTestCase):
         tmp_file = Path(black.dump_to_file(source))
         diff_header = re.compile(
             rf"{re.escape(str(tmp_file))}\t\d\d\d\d-\d\d-\d\d "
-            r"\d\d:\d\d:\d\d\.\d\d\d\d\d\d \+\d\d\d\d"
+            r"\d\d:\d\d:\d\d\.\d\d\d\d\d\d\+\d\d:\d\d"
         )
         try:
             result = BlackRunner().invoke(
@@ -380,8 +388,7 @@ class BlackTestCase(BlackBaseTestCase):
             black.main, [str(tmp_file), "-x", f"--config={EMPTY_CONFIG}"]
         )
         self.assertEqual(result.exit_code, 0)
-        with open(tmp_file, encoding="utf8") as f:
-            actual = f.read()
+        actual = tmp_file.read_text(encoding="utf-8")
         self.assertFormatEqual(source, actual)
 
     def test_skip_source_first_line_when_mixing_newlines(self) -> None:
@@ -402,7 +409,7 @@ class BlackTestCase(BlackBaseTestCase):
         tmp_file = Path(black.dump_to_file(source))
         diff_header = re.compile(
             rf"{re.escape(str(tmp_file))}\t\d\d\d\d-\d\d-\d\d "
-            r"\d\d:\d\d:\d\d\.\d\d\d\d\d\d \+\d\d\d\d"
+            r"\d\d:\d\d:\d\d\.\d\d\d\d\d\d\+\d\d:\d\d"
         )
         try:
             result = BlackRunner().invoke(
@@ -567,10 +574,8 @@ class BlackTestCase(BlackBaseTestCase):
             self.assertEqual(err_lines[-1], "error: cannot format e1: boom")
             self.assertEqual(
                 unstyle(str(report)),
-                (
-                    "1 file reformatted, 2 files left unchanged, 1 file failed to"
-                    " reformat."
-                ),
+                "1 file reformatted, 2 files left unchanged, 1 file failed to"
+                " reformat.",
             )
             self.assertEqual(report.return_code, 123)
             report.done(Path("f3"), black.Changed.YES)
@@ -579,10 +584,8 @@ class BlackTestCase(BlackBaseTestCase):
             self.assertEqual(out_lines[-1], "reformatted f3")
             self.assertEqual(
                 unstyle(str(report)),
-                (
-                    "2 files reformatted, 2 files left unchanged, 1 file failed to"
-                    " reformat."
-                ),
+                "2 files reformatted, 2 files left unchanged, 1 file failed to"
+                " reformat.",
             )
             self.assertEqual(report.return_code, 123)
             report.failed(Path("e2"), "boom")
@@ -591,10 +594,8 @@ class BlackTestCase(BlackBaseTestCase):
             self.assertEqual(err_lines[-1], "error: cannot format e2: boom")
             self.assertEqual(
                 unstyle(str(report)),
-                (
-                    "2 files reformatted, 2 files left unchanged, 2 files failed to"
-                    " reformat."
-                ),
+                "2 files reformatted, 2 files left unchanged, 2 files failed to"
+                " reformat.",
             )
             self.assertEqual(report.return_code, 123)
             report.path_ignored(Path("wat"), "no match")
@@ -603,10 +604,8 @@ class BlackTestCase(BlackBaseTestCase):
             self.assertEqual(out_lines[-1], "wat ignored: no match")
             self.assertEqual(
                 unstyle(str(report)),
-                (
-                    "2 files reformatted, 2 files left unchanged, 2 files failed to"
-                    " reformat."
-                ),
+                "2 files reformatted, 2 files left unchanged, 2 files failed to"
+                " reformat.",
             )
             self.assertEqual(report.return_code, 123)
             report.done(Path("f4"), black.Changed.NO)
@@ -615,28 +614,22 @@ class BlackTestCase(BlackBaseTestCase):
             self.assertEqual(out_lines[-1], "f4 already well formatted, good job.")
             self.assertEqual(
                 unstyle(str(report)),
-                (
-                    "2 files reformatted, 3 files left unchanged, 2 files failed to"
-                    " reformat."
-                ),
+                "2 files reformatted, 3 files left unchanged, 2 files failed to"
+                " reformat.",
             )
             self.assertEqual(report.return_code, 123)
             report.check = True
             self.assertEqual(
                 unstyle(str(report)),
-                (
-                    "2 files would be reformatted, 3 files would be left unchanged, 2"
-                    " files would fail to reformat."
-                ),
+                "2 files would be reformatted, 3 files would be left unchanged, 2"
+                " files would fail to reformat.",
             )
             report.check = False
             report.diff = True
             self.assertEqual(
                 unstyle(str(report)),
-                (
-                    "2 files would be reformatted, 3 files would be left unchanged, 2"
-                    " files would fail to reformat."
-                ),
+                "2 files would be reformatted, 3 files would be left unchanged, 2"
+                " files would fail to reformat.",
             )
 
     def test_report_quiet(self) -> None:
@@ -678,10 +671,8 @@ class BlackTestCase(BlackBaseTestCase):
             self.assertEqual(err_lines[-1], "error: cannot format e1: boom")
             self.assertEqual(
                 unstyle(str(report)),
-                (
-                    "1 file reformatted, 2 files left unchanged, 1 file failed to"
-                    " reformat."
-                ),
+                "1 file reformatted, 2 files left unchanged, 1 file failed to"
+                " reformat.",
             )
             self.assertEqual(report.return_code, 123)
             report.done(Path("f3"), black.Changed.YES)
@@ -689,10 +680,8 @@ class BlackTestCase(BlackBaseTestCase):
             self.assertEqual(len(err_lines), 1)
             self.assertEqual(
                 unstyle(str(report)),
-                (
-                    "2 files reformatted, 2 files left unchanged, 1 file failed to"
-                    " reformat."
-                ),
+                "2 files reformatted, 2 files left unchanged, 1 file failed to"
+                " reformat.",
             )
             self.assertEqual(report.return_code, 123)
             report.failed(Path("e2"), "boom")
@@ -701,10 +690,8 @@ class BlackTestCase(BlackBaseTestCase):
             self.assertEqual(err_lines[-1], "error: cannot format e2: boom")
             self.assertEqual(
                 unstyle(str(report)),
-                (
-                    "2 files reformatted, 2 files left unchanged, 2 files failed to"
-                    " reformat."
-                ),
+                "2 files reformatted, 2 files left unchanged, 2 files failed to"
+                " reformat.",
             )
             self.assertEqual(report.return_code, 123)
             report.path_ignored(Path("wat"), "no match")
@@ -712,10 +699,8 @@ class BlackTestCase(BlackBaseTestCase):
             self.assertEqual(len(err_lines), 2)
             self.assertEqual(
                 unstyle(str(report)),
-                (
-                    "2 files reformatted, 2 files left unchanged, 2 files failed to"
-                    " reformat."
-                ),
+                "2 files reformatted, 2 files left unchanged, 2 files failed to"
+                " reformat.",
             )
             self.assertEqual(report.return_code, 123)
             report.done(Path("f4"), black.Changed.NO)
@@ -723,28 +708,22 @@ class BlackTestCase(BlackBaseTestCase):
             self.assertEqual(len(err_lines), 2)
             self.assertEqual(
                 unstyle(str(report)),
-                (
-                    "2 files reformatted, 3 files left unchanged, 2 files failed to"
-                    " reformat."
-                ),
+                "2 files reformatted, 3 files left unchanged, 2 files failed to"
+                " reformat.",
             )
             self.assertEqual(report.return_code, 123)
             report.check = True
             self.assertEqual(
                 unstyle(str(report)),
-                (
-                    "2 files would be reformatted, 3 files would be left unchanged, 2"
-                    " files would fail to reformat."
-                ),
+                "2 files would be reformatted, 3 files would be left unchanged, 2"
+                " files would fail to reformat.",
             )
             report.check = False
             report.diff = True
             self.assertEqual(
                 unstyle(str(report)),
-                (
-                    "2 files would be reformatted, 3 files would be left unchanged, 2"
-                    " files would fail to reformat."
-                ),
+                "2 files would be reformatted, 3 files would be left unchanged, 2"
+                " files would fail to reformat.",
             )
 
     def test_report_normal(self) -> None:
@@ -788,10 +767,8 @@ class BlackTestCase(BlackBaseTestCase):
             self.assertEqual(err_lines[-1], "error: cannot format e1: boom")
             self.assertEqual(
                 unstyle(str(report)),
-                (
-                    "1 file reformatted, 2 files left unchanged, 1 file failed to"
-                    " reformat."
-                ),
+                "1 file reformatted, 2 files left unchanged, 1 file failed to"
+                " reformat.",
             )
             self.assertEqual(report.return_code, 123)
             report.done(Path("f3"), black.Changed.YES)
@@ -800,10 +777,8 @@ class BlackTestCase(BlackBaseTestCase):
             self.assertEqual(out_lines[-1], "reformatted f3")
             self.assertEqual(
                 unstyle(str(report)),
-                (
-                    "2 files reformatted, 2 files left unchanged, 1 file failed to"
-                    " reformat."
-                ),
+                "2 files reformatted, 2 files left unchanged, 1 file failed to"
+                " reformat.",
             )
             self.assertEqual(report.return_code, 123)
             report.failed(Path("e2"), "boom")
@@ -812,10 +787,8 @@ class BlackTestCase(BlackBaseTestCase):
             self.assertEqual(err_lines[-1], "error: cannot format e2: boom")
             self.assertEqual(
                 unstyle(str(report)),
-                (
-                    "2 files reformatted, 2 files left unchanged, 2 files failed to"
-                    " reformat."
-                ),
+                "2 files reformatted, 2 files left unchanged, 2 files failed to"
+                " reformat.",
             )
             self.assertEqual(report.return_code, 123)
             report.path_ignored(Path("wat"), "no match")
@@ -823,10 +796,8 @@ class BlackTestCase(BlackBaseTestCase):
             self.assertEqual(len(err_lines), 2)
             self.assertEqual(
                 unstyle(str(report)),
-                (
-                    "2 files reformatted, 2 files left unchanged, 2 files failed to"
-                    " reformat."
-                ),
+                "2 files reformatted, 2 files left unchanged, 2 files failed to"
+                " reformat.",
             )
             self.assertEqual(report.return_code, 123)
             report.done(Path("f4"), black.Changed.NO)
@@ -834,28 +805,22 @@ class BlackTestCase(BlackBaseTestCase):
             self.assertEqual(len(err_lines), 2)
             self.assertEqual(
                 unstyle(str(report)),
-                (
-                    "2 files reformatted, 3 files left unchanged, 2 files failed to"
-                    " reformat."
-                ),
+                "2 files reformatted, 3 files left unchanged, 2 files failed to"
+                " reformat.",
             )
             self.assertEqual(report.return_code, 123)
             report.check = True
             self.assertEqual(
                 unstyle(str(report)),
-                (
-                    "2 files would be reformatted, 3 files would be left unchanged, 2"
-                    " files would fail to reformat."
-                ),
+                "2 files would be reformatted, 3 files would be left unchanged, 2"
+                " files would fail to reformat.",
             )
             report.check = False
             report.diff = True
             self.assertEqual(
                 unstyle(str(report)),
-                (
-                    "2 files would be reformatted, 3 files would be left unchanged, 2"
-                    " files would fail to reformat."
-                ),
+                "2 files would be reformatted, 3 files would be left unchanged, 2"
+                " files would fail to reformat.",
             )
 
     def test_lib2to3_parse(self) -> None:
@@ -1113,7 +1078,7 @@ class BlackTestCase(BlackBaseTestCase):
                 (workspace / "one.py").resolve(),
                 (workspace / "two.py").resolve(),
             ]:
-                f.write_text('print("hello")\n')
+                f.write_text('print("hello")\n', encoding="utf-8")
             self.invokeBlack([str(workspace)])
 
     @event_loop()
@@ -1150,11 +1115,9 @@ class BlackTestCase(BlackBaseTestCase):
         contents, expected = read_data("miscellaneous", "force_pyi")
         with cache_dir() as workspace:
             path = (workspace / "file.py").resolve()
-            with open(path, "w") as fh:
-                fh.write(contents)
+            path.write_text(contents, encoding="utf-8")
             self.invokeBlack([str(path), "--pyi"])
-            with open(path, "r") as fh:
-                actual = fh.read()
+            actual = path.read_text(encoding="utf-8")
             # verify cache with --pyi is separate
             pyi_cache = black.read_cache(pyi_mode)
             self.assertIn(str(path), pyi_cache)
@@ -1175,12 +1138,10 @@ class BlackTestCase(BlackBaseTestCase):
                 (workspace / "file2.py").resolve(),
             ]
             for path in paths:
-                with open(path, "w") as fh:
-                    fh.write(contents)
+                path.write_text(contents, encoding="utf-8")
             self.invokeBlack([str(p) for p in paths] + ["--pyi"])
             for path in paths:
-                with open(path, "r") as fh:
-                    actual = fh.read()
+                actual = path.read_text(encoding="utf-8")
                 self.assertEqual(actual, expected)
             # verify cache with --pyi is separate
             pyi_cache = black.read_cache(pyi_mode)
@@ -1192,7 +1153,7 @@ class BlackTestCase(BlackBaseTestCase):
     def test_pipe_force_pyi(self) -> None:
         source, expected = read_data("miscellaneous", "force_pyi")
         result = CliRunner().invoke(
-            black.main, ["-", "-q", "--pyi"], input=BytesIO(source.encode("utf8"))
+            black.main, ["-", "-q", "--pyi"], input=BytesIO(source.encode("utf-8"))
         )
         self.assertEqual(result.exit_code, 0)
         actual = result.output
@@ -1204,11 +1165,9 @@ class BlackTestCase(BlackBaseTestCase):
         source, expected = read_data("miscellaneous", "force_py36")
         with cache_dir() as workspace:
             path = (workspace / "file.py").resolve()
-            with open(path, "w") as fh:
-                fh.write(source)
+            path.write_text(source, encoding="utf-8")
             self.invokeBlack([str(path), *PY36_ARGS])
-            with open(path, "r") as fh:
-                actual = fh.read()
+            actual = path.read_text(encoding="utf-8")
             # verify cache with --target-version is separate
             py36_cache = black.read_cache(py36_mode)
             self.assertIn(str(path), py36_cache)
@@ -1227,12 +1186,10 @@ class BlackTestCase(BlackBaseTestCase):
                 (workspace / "file2.py").resolve(),
             ]
             for path in paths:
-                with open(path, "w") as fh:
-                    fh.write(source)
+                path.write_text(source, encoding="utf-8")
             self.invokeBlack([str(p) for p in paths] + PY36_ARGS)
             for path in paths:
-                with open(path, "r") as fh:
-                    actual = fh.read()
+                actual = path.read_text(encoding="utf-8")
                 self.assertEqual(actual, expected)
             # verify cache with --target-version is separate
             pyi_cache = black.read_cache(py36_mode)
@@ -1246,7 +1203,7 @@ class BlackTestCase(BlackBaseTestCase):
         result = CliRunner().invoke(
             black.main,
             ["-", "-q", "--target-version=py36"],
-            input=BytesIO(source.encode("utf8")),
+            input=BytesIO(source.encode("utf-8")),
         )
         self.assertEqual(result.exit_code, 0)
         actual = result.output
@@ -1475,11 +1432,11 @@ class BlackTestCase(BlackBaseTestCase):
             contents = nl.join(["def f(  ):", "    pass"])
             runner = BlackRunner()
             result = runner.invoke(
-                black.main, ["-", "--fast"], input=BytesIO(contents.encode("utf8"))
+                black.main, ["-", "--fast"], input=BytesIO(contents.encode("utf-8"))
             )
             self.assertEqual(result.exit_code, 0)
             output = result.stdout_bytes
-            self.assertIn(nl.encode("utf8"), output)
+            self.assertIn(nl.encode("utf-8"), output)
             if nl == "\n":
                 self.assertNotIn(b"\r\n", output)
 
@@ -1575,14 +1532,25 @@ class BlackTestCase(BlackBaseTestCase):
         for version, expected in [
             ("3.6", [TargetVersion.PY36]),
             ("3.11.0rc1", [TargetVersion.PY311]),
-            (">=3.10", [TargetVersion.PY310, TargetVersion.PY311]),
-            (">=3.10.6", [TargetVersion.PY310, TargetVersion.PY311]),
+            (">=3.10", [TargetVersion.PY310, TargetVersion.PY311, TargetVersion.PY312]),
+            (
+                ">=3.10.6",
+                [TargetVersion.PY310, TargetVersion.PY311, TargetVersion.PY312],
+            ),
             ("<3.6", [TargetVersion.PY33, TargetVersion.PY34, TargetVersion.PY35]),
             (">3.7,<3.10", [TargetVersion.PY38, TargetVersion.PY39]),
-            (">3.7,!=3.8,!=3.9", [TargetVersion.PY310, TargetVersion.PY311]),
+            (
+                ">3.7,!=3.8,!=3.9",
+                [TargetVersion.PY310, TargetVersion.PY311, TargetVersion.PY312],
+            ),
             (
                 "> 3.9.4, != 3.10.3",
-                [TargetVersion.PY39, TargetVersion.PY310, TargetVersion.PY311],
+                [
+                    TargetVersion.PY39,
+                    TargetVersion.PY310,
+                    TargetVersion.PY311,
+                    TargetVersion.PY312,
+                ],
             ),
             (
                 "!=3.3,!=3.4",
@@ -1594,6 +1562,7 @@ class BlackTestCase(BlackBaseTestCase):
                     TargetVersion.PY39,
                     TargetVersion.PY310,
                     TargetVersion.PY311,
+                    TargetVersion.PY312,
                 ],
             ),
             (
@@ -1608,6 +1577,7 @@ class BlackTestCase(BlackBaseTestCase):
                     TargetVersion.PY39,
                     TargetVersion.PY310,
                     TargetVersion.PY311,
+                    TargetVersion.PY312,
                 ],
             ),
             ("==3.8.*", [TargetVersion.PY38]),
@@ -1640,6 +1610,39 @@ class BlackTestCase(BlackBaseTestCase):
         self.assertEqual(config["exclude"], r"\.pyi?$")
         self.assertEqual(config["include"], r"\.py?$")
 
+    def test_read_pyproject_toml_from_stdin(self) -> None:
+        with TemporaryDirectory() as workspace:
+            root = Path(workspace)
+
+            src_dir = root / "src"
+            src_dir.mkdir()
+
+            src_pyproject = src_dir / "pyproject.toml"
+            src_pyproject.touch()
+
+            test_toml_content = (THIS_DIR / "test.toml").read_text(encoding="utf-8")
+            src_pyproject.write_text(test_toml_content, encoding="utf-8")
+
+            src_python = src_dir / "foo.py"
+            src_python.touch()
+
+            fake_ctx = FakeContext()
+            fake_ctx.params["src"] = ("-",)
+            fake_ctx.params["stdin_filename"] = str(src_python)
+
+            with change_directory(root):
+                black.read_pyproject_toml(fake_ctx, FakeParameter(), None)
+
+            config = fake_ctx.default_map
+            self.assertEqual(config["verbose"], "1")
+            self.assertEqual(config["check"], "no")
+            self.assertEqual(config["diff"], "y")
+            self.assertEqual(config["color"], "True")
+            self.assertEqual(config["line_length"], "79")
+            self.assertEqual(config["target_version"], ["py36", "py37", "py38"])
+            self.assertEqual(config["exclude"], r"\.pyi?$")
+            self.assertEqual(config["include"], r"\.py?$")
+
     @pytest.mark.incompatible_with_mypyc
     def test_find_project_root(self) -> None:
         with TemporaryDirectory() as workspace:
@@ -1770,7 +1773,7 @@ class BlackTestCase(BlackBaseTestCase):
         tmp_file = Path(black.dump_to_file(source, ensure_final_newline=False))
         diff_header = re.compile(
             rf"{re.escape(str(tmp_file))}\t\d\d\d\d-\d\d-\d\d "
-            r"\d\d:\d\d:\d\d\.\d\d\d\d\d\d \+\d\d\d\d"
+            r"\d\d:\d\d:\d\d\.\d\d\d\d\d\d\+\d\d:\d\d"
         )
         try:
             result = BlackRunner().invoke(black.main, ["--diff", str(tmp_file)])
@@ -1971,10 +1974,10 @@ class TestCaching:
         mode = DEFAULT_MODE
         with cache_dir() as workspace:
             cache_file = get_cache_file(mode)
-            cache_file.write_text("this is not a pickle")
+            cache_file.write_text("this is not a pickle", encoding="utf-8")
             assert black.read_cache(mode) == {}
             src = (workspace / "test.py").resolve()
-            src.write_text("print('hello')")
+            src.write_text("print('hello')", encoding="utf-8")
             invokeBlack([str(src)])
             cache = black.read_cache(mode)
             assert str(src) in cache
@@ -1983,10 +1986,10 @@ class TestCaching:
         mode = DEFAULT_MODE
         with cache_dir() as workspace:
             src = (workspace / "test.py").resolve()
-            src.write_text("print('hello')")
+            src.write_text("print('hello')", encoding="utf-8")
             black.write_cache({}, [src], mode)
             invokeBlack([str(src)])
-            assert src.read_text() == "print('hello')"
+            assert src.read_text(encoding="utf-8") == "print('hello')"
 
     @event_loop()
     def test_cache_multiple_files(self) -> None:
@@ -1995,17 +1998,13 @@ class TestCaching:
             "concurrent.futures.ProcessPoolExecutor", new=ThreadPoolExecutor
         ):
             one = (workspace / "one.py").resolve()
-            with one.open("w") as fobj:
-                fobj.write("print('hello')")
+            one.write_text("print('hello')", encoding="utf-8")
             two = (workspace / "two.py").resolve()
-            with two.open("w") as fobj:
-                fobj.write("print('hello')")
+            two.write_text("print('hello')", encoding="utf-8")
             black.write_cache({}, [one], mode)
             invokeBlack([str(workspace)])
-            with one.open("r") as fobj:
-                assert fobj.read() == "print('hello')"
-            with two.open("r") as fobj:
-                assert fobj.read() == 'print("hello")\n'
+            assert one.read_text(encoding="utf-8") == "print('hello')"
+            assert two.read_text(encoding="utf-8") == 'print("hello")\n'
             cache = black.read_cache(mode)
             assert str(one) in cache
             assert str(two) in cache
@@ -2015,8 +2014,7 @@ class TestCaching:
         mode = DEFAULT_MODE
         with cache_dir() as workspace:
             src = (workspace / "test.py").resolve()
-            with src.open("w") as fobj:
-                fobj.write("print('hello')")
+            src.write_text("print('hello')", encoding="utf-8")
             with patch("black.read_cache") as read_cache, patch(
                 "black.write_cache"
             ) as write_cache:
@@ -2035,8 +2033,7 @@ class TestCaching:
         with cache_dir() as workspace:
             for tag in range(0, 4):
                 src = (workspace / f"test{tag}.py").resolve()
-                with src.open("w") as fobj:
-                    fobj.write("print('hello')")
+                src.write_text("print('hello')", encoding="utf-8")
             with patch(
                 "black.concurrency.Manager", wraps=multiprocessing.Manager
             ) as mgr:
@@ -2106,11 +2103,9 @@ class TestCaching:
             "concurrent.futures.ProcessPoolExecutor", new=ThreadPoolExecutor
         ):
             failing = (workspace / "failing.py").resolve()
-            with failing.open("w") as fobj:
-                fobj.write("not actually python")
+            failing.write_text("not actually python", encoding="utf-8")
             clean = (workspace / "clean.py").resolve()
-            with clean.open("w") as fobj:
-                fobj.write('print("hello")\n')
+            clean.write_text('print("hello")\n', encoding="utf-8")
             invokeBlack([str(workspace)], exit_code=123)
             cache = black.read_cache(mode)
             assert str(failing) not in cache