# Licensed under the LGPL: https://www.gnu.org/licenses/old-licenses/lgpl-2.1.en.html # For details: https://github.com/PyCQA/astroid/blob/main/LICENSE # Copyright (c) https://github.com/PyCQA/astroid/blob/main/CONTRIBUTORS.txt from __future__ import annotations from astroid import context, inference_tip, nodes from astroid.brain.helpers import register_module_extender from astroid.builder import _extract_single_node, parse from astroid.const import PY39_PLUS from astroid.manager import AstroidManager def _regex_transform() -> nodes.Module: """The RegexFlag enum exposes all its entries by updating globals(). We hard-code the flags for now. # pylint: disable-next=line-too-long See https://github.com/mrabarnett/mrab-regex/blob/2022.10.31/regex_3/regex.py#L200 """ return parse( """ A = ASCII = 0x80 # Assume ASCII locale. B = BESTMATCH = 0x1000 # Best fuzzy match. D = DEBUG = 0x200 # Print parsed pattern. E = ENHANCEMATCH = 0x8000 # Attempt to improve the fit after finding the first # fuzzy match. F = FULLCASE = 0x4000 # Unicode full case-folding. I = IGNORECASE = 0x2 # Ignore case. L = LOCALE = 0x4 # Assume current 8-bit locale. M = MULTILINE = 0x8 # Make anchors look for newline. P = POSIX = 0x10000 # POSIX-style matching (leftmost longest). R = REVERSE = 0x400 # Search backwards. S = DOTALL = 0x10 # Make dot match newline. U = UNICODE = 0x20 # Assume Unicode locale. V0 = VERSION0 = 0x2000 # Old legacy behaviour. DEFAULT_VERSION = V0 V1 = VERSION1 = 0x100 # New enhanced behaviour. W = WORD = 0x800 # Default Unicode word breaks. X = VERBOSE = 0x40 # Ignore whitespace and comments. T = TEMPLATE = 0x1 # Template (present because re module has it). """ ) register_module_extender(AstroidManager(), "regex", _regex_transform) CLASS_GETITEM_TEMPLATE = """ @classmethod def __class_getitem__(cls, item): return cls """ def _looks_like_pattern_or_match(node: nodes.Call) -> bool: """Check for regex.Pattern or regex.Match call in stdlib. Match these patterns from stdlib/re.py ```py Pattern = type(...) Match = type(...) ``` """ return ( node.root().name == "regex.regex" and isinstance(node.func, nodes.Name) and node.func.name == "type" and isinstance(node.parent, nodes.Assign) and len(node.parent.targets) == 1 and isinstance(node.parent.targets[0], nodes.AssignName) and node.parent.targets[0].name in {"Pattern", "Match"} ) def infer_pattern_match(node: nodes.Call, ctx: context.InferenceContext | None = None): """Infer regex.Pattern and regex.Match as classes. For PY39+ add `__class_getitem__`. """ class_def = nodes.ClassDef( name=node.parent.targets[0].name, lineno=node.lineno, col_offset=node.col_offset, parent=node.parent, ) if PY39_PLUS: func_to_add = _extract_single_node(CLASS_GETITEM_TEMPLATE) class_def.locals["__class_getitem__"] = [func_to_add] return iter([class_def]) AstroidManager().register_transform( nodes.Call, inference_tip(infer_pattern_match), _looks_like_pattern_or_match )