From: Felix Hildén Date: Tue, 13 Jul 2021 17:24:55 +0000 (+0300) Subject: Improve AST safety parsing error message (#2304) X-Git-Url: https://git.madduck.net/etc/vim.git/commitdiff_plain/91773b89097927a2393bc5223295d37ed26e1632?ds=sidebyside Improve AST safety parsing error message (#2304) Co-authored-by: Hasan Ramezani --- diff --git a/CHANGES.md b/CHANGES.md index 611094f..b3224e1 100644 --- a/CHANGES.md +++ b/CHANGES.md @@ -20,6 +20,7 @@ - Fixed option usage when using the `--code` flag (#2259) - Do not call `uvloop.install()` when _Black_ is used as a library (#2303) - Added `--required-version` option to require a specific version to be running (#2300) +- Provide a more useful error when parsing fails during AST safety checks (#2304) - Fix incorrect custom breakpoint indices when string group contains fake f-strings (#2311) - Fix regression where `R` prefixes would be lowercased for docstrings (#2285) diff --git a/src/black/parsing.py b/src/black/parsing.py index 8e9feea..0b8d984 100644 --- a/src/black/parsing.py +++ b/src/black/parsing.py @@ -3,7 +3,7 @@ Parse Python code and perform AST validation. """ import ast import sys -from typing import Iterable, Iterator, List, Set, Union +from typing import Iterable, Iterator, List, Set, Union, Tuple # lib2to3 fork from blib2to3.pytree import Node, Leaf @@ -106,28 +106,36 @@ def lib2to3_unparse(node: Node) -> str: return code -def parse_ast(src: str) -> Union[ast.AST, ast3.AST, ast27.AST]: +def parse_single_version( + src: str, version: Tuple[int, int] +) -> Union[ast.AST, ast3.AST, ast27.AST]: filename = "" - if sys.version_info >= (3, 8): - # TODO: support Python 4+ ;) - for minor_version in range(sys.version_info[1], 4, -1): - try: - return ast.parse(src, filename, feature_version=(3, minor_version)) - except SyntaxError: - continue - else: - for feature_version in (7, 6): - try: - return ast3.parse(src, filename, feature_version=feature_version) - except SyntaxError: - continue - if ast27.__name__ == "ast": - raise SyntaxError( - "The requested source code has invalid Python 3 syntax.\n" - "If you are trying to format Python 2 files please reinstall Black" - " with the 'python2' extra: `python3 -m pip install black[python2]`." - ) - return ast27.parse(src) + # typed_ast is needed because of feature version limitations in the builtin ast + if sys.version_info >= (3, 8) and version >= (3,): + return ast.parse(src, filename, feature_version=version) + elif version >= (3,): + return ast3.parse(src, filename, feature_version=version[1]) + elif version == (2, 7): + return ast27.parse(src) + raise AssertionError("INTERNAL ERROR: Tried parsing unsupported Python version!") + + +def parse_ast(src: str) -> Union[ast.AST, ast3.AST, ast27.AST]: + # TODO: support Python 4+ ;) + versions = [(3, minor) for minor in range(3, sys.version_info[1] + 1)] + + if ast27.__name__ != "ast": + versions.append((2, 7)) + + first_error = "" + for version in sorted(versions, reverse=True): + try: + return parse_single_version(src, version) + except SyntaxError as e: + if not first_error: + first_error = str(e) + + raise SyntaxError(first_error) def stringify_ast( diff --git a/tests/test_black.py b/tests/test_black.py index 42ac119..e3be9c7 100644 --- a/tests/test_black.py +++ b/tests/test_black.py @@ -451,38 +451,6 @@ 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: