add context manager to temporarily change the cwd (#2377)

[etc/vim.git] / tests / test_black.py

diff --git a/tests/test_black.py b/tests/test_black.py
index 5262c0ee44c4e09d2e6f44130179c59a5aa9247b..998ecfcbdebfe8b1968046ec62ef206030609e0b 100644 (file)
--- a/tests/test_black.py
+++ b/tests/test_black.py
@@ -6,6 +6,7 @@ from concurrent.futures import ThreadPoolExecutor
 from contextlib import contextmanager
 from dataclasses import replace
 import inspect
+import io
 from io import BytesIO
 import os
 from pathlib import Path
@@ -43,6 +44,7 @@ from pathspec import PathSpec
 # Import other test classes
 from tests.util import (
     THIS_DIR,
+    change_directory,
     read_data,
     DETERMINISTIC_HEADER,
     BlackBaseTestCase,
@@ -450,38 +452,6 @@ class BlackTestCase(BlackBaseTestCase):
             )
             self.assertEqual(expected, actual, msg)
 
-    @pytest.mark.no_python2
-    def test_python2_should_fail_without_optional_install(self) -> None:
-        if sys.version_info < (3, 8):
-            self.skipTest(
-                "Python 3.6 and 3.7 will install typed-ast to work and as such will be"
-                " able to parse Python 2 syntax without explicitly specifying the"
-                " python2 extra"
-            )
-
-        source = "x = 1234l"
-        tmp_file = Path(black.dump_to_file(source))
-        try:
-            runner = BlackRunner()
-            result = runner.invoke(black.main, [str(tmp_file)])
-            self.assertEqual(result.exit_code, 123)
-        finally:
-            os.unlink(tmp_file)
-        assert result.stderr_bytes is not None
-        actual = (
-            result.stderr_bytes.decode()
-            .replace("\n", "")
-            .replace("\\n", "")
-            .replace("\\r", "")
-            .replace("\r", "")
-        )
-        msg = (
-            "The requested source code has invalid Python 3 syntax."
-            "If you are trying to format Python 2 files please reinstall Black"
-            " with the 'python2' extra: `python3 -m pip install black[python2]`."
-        )
-        self.assertIn(msg, actual)
-
     @pytest.mark.python2
     @patch("black.dump_to_file", dump_to_stderr)
     def test_python2_print_function(self) -> None:
@@ -1682,6 +1652,20 @@ class BlackTestCase(BlackBaseTestCase):
             # __BLACK_STDIN_FILENAME__ should have been stripped
             report.done.assert_called_with(expected, black.Changed.YES)
 
+    def test_reformat_one_with_stdin_empty(self) -> None:
+        output = io.StringIO()
+        with patch("io.TextIOWrapper", lambda *args, **kwargs: output):
+            try:
+                black.format_stdin_to_stdout(
+                    fast=True,
+                    content="",
+                    write_back=black.WriteBack.YES,
+                    mode=DEFAULT_MODE,
+                )
+            except io.UnsupportedOperation:
+                pass  # StringIO does not support detach
+            assert output.getvalue() == ""
+
     def test_gitignore_exclude(self) -> None:
         path = THIS_DIR / "data" / "include_exclude_tests"
         include = re.compile(r"\.pyi?$")
@@ -2026,17 +2010,12 @@ class BlackTestCase(BlackBaseTestCase):
             return
 
         # https://bugs.python.org/issue33660
-
-        old_cwd = Path.cwd()
-        try:
-            root = Path("/")
-            os.chdir(str(root))
+        root = Path("/")
+        with change_directory(root):
             path = Path("workspace") / "project"
             report = black.Report(verbose=True)
             normalized_path = black.normalize_path_maybe_ignore(path, root, report)
             self.assertEqual(normalized_path, "workspace/project")
-        finally:
-            os.chdir(str(old_cwd))
 
     def test_newline_comment_interaction(self) -> None:
         source = "class A:\\\r\n# type: ignore\n pass\n"
@@ -2187,10 +2166,6 @@ class BlackTestCase(BlackBaseTestCase):
         Test that the code option finds the pyproject.toml in the current directory.
         """
         with patch.object(black, "parse_pyproject_toml", return_value={}) as parse:
-            # Make sure we are in the project root with the pyproject file
-            if not Path("tests").exists():
-                os.chdir("..")
-
             args = ["--code", "print"]
             CliRunner().invoke(black.main, args)
 
@@ -2209,22 +2184,19 @@ class BlackTestCase(BlackBaseTestCase):
         Test that the code option finds the pyproject.toml in the parent directory.
         """
         with patch.object(black, "parse_pyproject_toml", return_value={}) as parse:
-            # Make sure we are in the tests directory
-            if Path("tests").exists():
-                os.chdir("tests")
-
-            args = ["--code", "print"]
-            CliRunner().invoke(black.main, args)
-
-            pyproject_path = Path(Path().cwd().parent, "pyproject.toml").resolve()
-            assert (
-                len(parse.mock_calls) >= 1
-            ), "Expected config parse to be called with the current directory."
-
-            _, call_args, _ = parse.mock_calls[0]
-            assert (
-                call_args[0].lower() == str(pyproject_path).lower()
-            ), "Incorrect config loaded."
+            with change_directory(Path("tests")):
+                args = ["--code", "print"]
+                CliRunner().invoke(black.main, args)
+
+                pyproject_path = Path(Path().cwd().parent, "pyproject.toml").resolve()
+                assert (
+                    len(parse.mock_calls) >= 1
+                ), "Expected config parse to be called with the current directory."
+
+                _, call_args, _ = parse.mock_calls[0]
+                assert (
+                    call_args[0].lower() == str(pyproject_path).lower()
+                ), "Incorrect config loaded."
 
 
 with open(black.__file__, "r", encoding="utf-8") as _bf: