]> git.madduck.net Git - etc/vim.git/blob - tests/util.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:

Bump typed-ast minimum to 1.4.3 for 3.10 compat (#2519)
[etc/vim.git] / tests / util.py
1 import os
2 import sys
3 import unittest
4 from contextlib import contextmanager
5 from functools import partial
6 from pathlib import Path
7 from typing import Any, Iterator, List, Optional, Tuple
8
9 import black
10 from black.debug import DebugVisitor
11 from black.mode import TargetVersion
12 from black.output import err, out
13
14 THIS_DIR = Path(__file__).parent
15 DATA_DIR = THIS_DIR / "data"
16 PROJECT_ROOT = THIS_DIR.parent
17 EMPTY_LINE = "# EMPTY LINE WITH WHITESPACE" + " (this comment will be removed)"
18 DETERMINISTIC_HEADER = "[Deterministic header]"
19
20 PY36_VERSIONS = {
21     TargetVersion.PY36,
22     TargetVersion.PY37,
23     TargetVersion.PY38,
24     TargetVersion.PY39,
25 }
26
27 DEFAULT_MODE = black.Mode()
28 ff = partial(black.format_file_in_place, mode=DEFAULT_MODE, fast=True)
29 fs = partial(black.format_str, mode=DEFAULT_MODE)
30
31
32 def _assert_format_equal(expected: str, actual: str) -> None:
33     if actual != expected and not os.environ.get("SKIP_AST_PRINT"):
34         bdv: DebugVisitor[Any]
35         out("Expected tree:", fg="green")
36         try:
37             exp_node = black.lib2to3_parse(expected)
38             bdv = DebugVisitor()
39             list(bdv.visit(exp_node))
40         except Exception as ve:
41             err(str(ve))
42         out("Actual tree:", fg="red")
43         try:
44             exp_node = black.lib2to3_parse(actual)
45             bdv = DebugVisitor()
46             list(bdv.visit(exp_node))
47         except Exception as ve:
48             err(str(ve))
49
50     assert actual == expected
51
52
53 def assert_format(
54     source: str,
55     expected: str,
56     mode: black.Mode = DEFAULT_MODE,
57     *,
58     fast: bool = False,
59     minimum_version: Optional[Tuple[int, int]] = None,
60 ) -> None:
61     """Convenience function to check that Black formats as expected.
62
63     You can pass @minimum_version if you're passing code with newer syntax to guard
64     safety guards so they don't just crash with a SyntaxError. Please note this is
65     separate from TargetVerson Mode configuration.
66     """
67     actual = black.format_str(source, mode=mode)
68     _assert_format_equal(expected, actual)
69     # It's not useful to run safety checks if we're expecting no changes anyway. The
70     # assertion right above will raise if reality does actually make changes. This just
71     # avoids wasted CPU cycles.
72     if not fast and source != expected:
73         # Unfortunately the AST equivalence check relies on the built-in ast module
74         # being able to parse the code being formatted. This doesn't always work out
75         # when checking modern code on older versions.
76         if minimum_version is None or sys.version_info >= minimum_version:
77             black.assert_equivalent(source, actual)
78         black.assert_stable(source, actual, mode=mode)
79
80
81 def dump_to_stderr(*output: str) -> str:
82     return "\n" + "\n".join(output) + "\n"
83
84
85 class BlackBaseTestCase(unittest.TestCase):
86     def assertFormatEqual(self, expected: str, actual: str) -> None:
87         _assert_format_equal(expected, actual)
88
89
90 def read_data(name: str, data: bool = True) -> Tuple[str, str]:
91     """read_data('test_name') -> 'input', 'output'"""
92     if not name.endswith((".py", ".pyi", ".out", ".diff")):
93         name += ".py"
94     base_dir = DATA_DIR if data else PROJECT_ROOT
95     return read_data_from_file(base_dir / name)
96
97
98 def read_data_from_file(file_name: Path) -> Tuple[str, str]:
99     with open(file_name, "r", encoding="utf8") as test:
100         lines = test.readlines()
101     _input: List[str] = []
102     _output: List[str] = []
103     result = _input
104     for line in lines:
105         line = line.replace(EMPTY_LINE, "")
106         if line.rstrip() == "# output":
107             result = _output
108             continue
109
110         result.append(line)
111     if _input and not _output:
112         # If there's no output marker, treat the entire file as already pre-formatted.
113         _output = _input[:]
114     return "".join(_input).strip() + "\n", "".join(_output).strip() + "\n"
115
116
117 @contextmanager
118 def change_directory(path: Path) -> Iterator[None]:
119     """Context manager to temporarily chdir to a different directory."""
120     previous_dir = os.getcwd()
121     try:
122         os.chdir(path)
123         yield
124     finally:
125         os.chdir(previous_dir)