import os
+import sys
import unittest
-from pathlib import Path
-from typing import Iterator, List, Tuple, Any
from contextlib import contextmanager
+from dataclasses import replace
from functools import partial
+from pathlib import Path
+from typing import Any, Iterator, List, Optional, Tuple
import black
-from black.output import out, err
from black.debug import DebugVisitor
+from black.mode import TargetVersion
+from black.output import diff, err, out
+
+from . import conftest
+
+PYTHON_SUFFIX = ".py"
+ALLOWED_SUFFIXES = (PYTHON_SUFFIX, ".pyi", ".out", ".diff", ".ipynb")
THIS_DIR = Path(__file__).parent
+DATA_DIR = THIS_DIR / "data"
PROJECT_ROOT = THIS_DIR.parent
EMPTY_LINE = "# EMPTY LINE WITH WHITESPACE" + " (this comment will be removed)"
DETERMINISTIC_HEADER = "[Deterministic header]"
+PY36_VERSIONS = {
+ TargetVersion.PY36,
+ TargetVersion.PY37,
+ TargetVersion.PY38,
+ TargetVersion.PY39,
+}
DEFAULT_MODE = black.Mode()
ff = partial(black.format_file_in_place, mode=DEFAULT_MODE, fast=True)
fs = partial(black.format_str, mode=DEFAULT_MODE)
+def _assert_format_equal(expected: str, actual: str) -> None:
+ if actual != expected and (conftest.PRINT_FULL_TREE or conftest.PRINT_TREE_DIFF):
+ bdv: DebugVisitor[Any]
+ actual_out: str = ""
+ expected_out: str = ""
+ if conftest.PRINT_FULL_TREE:
+ out("Expected tree:", fg="green")
+ try:
+ exp_node = black.lib2to3_parse(expected)
+ bdv = DebugVisitor(print_output=conftest.PRINT_FULL_TREE)
+ list(bdv.visit(exp_node))
+ expected_out = "\n".join(bdv.list_output)
+ except Exception as ve:
+ err(str(ve))
+ if conftest.PRINT_FULL_TREE:
+ out("Actual tree:", fg="red")
+ try:
+ exp_node = black.lib2to3_parse(actual)
+ bdv = DebugVisitor(print_output=conftest.PRINT_FULL_TREE)
+ list(bdv.visit(exp_node))
+ actual_out = "\n".join(bdv.list_output)
+ except Exception as ve:
+ err(str(ve))
+ if conftest.PRINT_TREE_DIFF:
+ out("Tree Diff:")
+ out(
+ diff(expected_out, actual_out, "expected tree", "actual tree")
+ or "Trees do not differ"
+ )
+
+ if actual != expected:
+ out(diff(expected, actual, "expected", "actual"))
+
+ assert actual == expected
+
+
+class FormatFailure(Exception):
+ """Used to wrap failures when assert_format() runs in an extra mode."""
+
+
+def assert_format(
+ source: str,
+ expected: str,
+ mode: black.Mode = DEFAULT_MODE,
+ *,
+ fast: bool = False,
+ minimum_version: Optional[Tuple[int, int]] = None,
+) -> None:
+ """Convenience function to check that Black formats as expected.
+
+ You can pass @minimum_version if you're passing code with newer syntax to guard
+ safety guards so they don't just crash with a SyntaxError. Please note this is
+ separate from TargetVerson Mode configuration.
+ """
+ _assert_format_inner(
+ source, expected, mode, fast=fast, minimum_version=minimum_version
+ )
+
+ # For both preview and non-preview tests, ensure that Black doesn't crash on
+ # this code, but don't pass "expected" because the precise output may differ.
+ try:
+ _assert_format_inner(
+ source,
+ None,
+ replace(mode, preview=not mode.preview),
+ fast=fast,
+ minimum_version=minimum_version,
+ )
+ except Exception as e:
+ text = "non-preview" if mode.preview else "preview"
+ raise FormatFailure(
+ f"Black crashed formatting this case in {text} mode."
+ ) from e
+ # Similarly, setting line length to 1 is a good way to catch
+ # stability bugs. But only in non-preview mode because preview mode
+ # currently has a lot of line length 1 bugs.
+ try:
+ _assert_format_inner(
+ source,
+ None,
+ replace(mode, preview=False, line_length=1),
+ fast=fast,
+ minimum_version=minimum_version,
+ )
+ except Exception as e:
+ raise FormatFailure(
+ "Black crashed formatting this case with line-length set to 1."
+ ) from e
+
+
+def _assert_format_inner(
+ source: str,
+ expected: Optional[str] = None,
+ mode: black.Mode = DEFAULT_MODE,
+ *,
+ fast: bool = False,
+ minimum_version: Optional[Tuple[int, int]] = None,
+) -> None:
+ actual = black.format_str(source, mode=mode)
+ if expected is not None:
+ _assert_format_equal(expected, actual)
+ # It's not useful to run safety checks if we're expecting no changes anyway. The
+ # assertion right above will raise if reality does actually make changes. This just
+ # avoids wasted CPU cycles.
+ if not fast and source != actual:
+ # Unfortunately the AST equivalence check relies on the built-in ast module
+ # being able to parse the code being formatted. This doesn't always work out
+ # when checking modern code on older versions.
+ if minimum_version is None or sys.version_info >= minimum_version:
+ black.assert_equivalent(source, actual)
+ black.assert_stable(source, actual, mode=mode)
+
+
def dump_to_stderr(*output: str) -> str:
return "\n" + "\n".join(output) + "\n"
class BlackBaseTestCase(unittest.TestCase):
- maxDiff = None
- _diffThreshold = 2 ** 20
-
def assertFormatEqual(self, expected: str, actual: str) -> None:
- if actual != expected and not os.environ.get("SKIP_AST_PRINT"):
- bdv: DebugVisitor[Any]
- out("Expected tree:", fg="green")
- try:
- exp_node = black.lib2to3_parse(expected)
- bdv = DebugVisitor()
- list(bdv.visit(exp_node))
- except Exception as ve:
- err(str(ve))
- out("Actual tree:", fg="red")
- try:
- exp_node = black.lib2to3_parse(actual)
- bdv = DebugVisitor()
- list(bdv.visit(exp_node))
- except Exception as ve:
- err(str(ve))
- self.assertMultiLineEqual(expected, actual)
+ _assert_format_equal(expected, actual)
+
+
+def get_base_dir(data: bool) -> Path:
+ return DATA_DIR if data else PROJECT_ROOT
+
+
+def all_data_cases(subdir_name: str, data: bool = True) -> List[str]:
+ cases_dir = get_base_dir(data) / subdir_name
+ assert cases_dir.is_dir()
+ return [case_path.stem for case_path in cases_dir.iterdir()]
+
+def get_case_path(
+ subdir_name: str, name: str, data: bool = True, suffix: str = PYTHON_SUFFIX
+) -> Path:
+ """Get case path from name"""
+ case_path = get_base_dir(data) / subdir_name / name
+ if not name.endswith(ALLOWED_SUFFIXES):
+ case_path = case_path.with_suffix(suffix)
+ assert case_path.is_file(), f"{case_path} is not a file."
+ return case_path
-def read_data(name: str, data: bool = True) -> Tuple[str, str]:
+
+def read_data(subdir_name: str, name: str, data: bool = True) -> Tuple[str, str]:
"""read_data('test_name') -> 'input', 'output'"""
- if not name.endswith((".py", ".pyi", ".out", ".diff")):
- name += ".py"
- base_dir = THIS_DIR / "data" if data else PROJECT_ROOT
- return read_data_from_file(base_dir / name)
+ return read_data_from_file(get_case_path(subdir_name, name, data))
def read_data_from_file(file_name: Path) -> Tuple[str, str]:
return "".join(_input).strip() + "\n", "".join(_output).strip() + "\n"
+def read_jupyter_notebook(subdir_name: str, name: str, data: bool = True) -> str:
+ return read_jupyter_notebook_from_file(
+ get_case_path(subdir_name, name, data, suffix=".ipynb")
+ )
+
+
+def read_jupyter_notebook_from_file(file_name: Path) -> str:
+ with open(file_name, mode="rb") as fd:
+ content_bytes = fd.read()
+ return content_bytes.decode()
+
+
@contextmanager
def change_directory(path: Path) -> Iterator[None]:
"""Context manager to temporarily chdir to a different directory."""
projects / etc / vim.git / blobdiff