| # This file is dual licensed under the terms of the Apache License, Version |
| # 2.0, and the BSD License. See the LICENSE file in the root of this repository |
| # for complete details. |
| |
| import operator |
| import os |
| import platform |
| import sys |
| from typing import Any, Callable, Dict, List, Optional, Tuple, Union |
| |
| from pip._vendor.pyparsing import ( # noqa: N817 |
| Forward, |
| Group, |
| Literal as L, |
| ParseException, |
| ParseResults, |
| QuotedString, |
| ZeroOrMore, |
| stringEnd, |
| stringStart, |
| ) |
| |
| from .specifiers import InvalidSpecifier, Specifier |
| |
| __all__ = [ |
| "InvalidMarker", |
| "UndefinedComparison", |
| "UndefinedEnvironmentName", |
| "Marker", |
| "default_environment", |
| ] |
| |
| Operator = Callable[[str, str], bool] |
| |
| |
| class InvalidMarker(ValueError): |
| """ |
| An invalid marker was found, users should refer to PEP 508. |
| """ |
| |
| |
| class UndefinedComparison(ValueError): |
| """ |
| An invalid operation was attempted on a value that doesn't support it. |
| """ |
| |
| |
| class UndefinedEnvironmentName(ValueError): |
| """ |
| A name was attempted to be used that does not exist inside of the |
| environment. |
| """ |
| |
| |
| class Node: |
| def __init__(self, value: Any) -> None: |
| self.value = value |
| |
| def __str__(self) -> str: |
| return str(self.value) |
| |
| def __repr__(self) -> str: |
| return f"<{self.__class__.__name__}('{self}')>" |
| |
| def serialize(self) -> str: |
| raise NotImplementedError |
| |
| |
| class Variable(Node): |
| def serialize(self) -> str: |
| return str(self) |
| |
| |
| class Value(Node): |
| def serialize(self) -> str: |
| return f'"{self}"' |
| |
| |
| class Op(Node): |
| def serialize(self) -> str: |
| return str(self) |
| |
| |
| VARIABLE = ( |
| L("implementation_version") |
| | L("platform_python_implementation") |
| | L("implementation_name") |
| | L("python_full_version") |
| | L("platform_release") |
| | L("platform_version") |
| | L("platform_machine") |
| | L("platform_system") |
| | L("python_version") |
| | L("sys_platform") |
| | L("os_name") |
| | L("os.name") # PEP-345 |
| | L("sys.platform") # PEP-345 |
| | L("platform.version") # PEP-345 |
| | L("platform.machine") # PEP-345 |
| | L("platform.python_implementation") # PEP-345 |
| | L("python_implementation") # undocumented setuptools legacy |
| | L("extra") # PEP-508 |
| ) |
| ALIASES = { |
| "os.name": "os_name", |
| "sys.platform": "sys_platform", |
| "platform.version": "platform_version", |
| "platform.machine": "platform_machine", |
| "platform.python_implementation": "platform_python_implementation", |
| "python_implementation": "platform_python_implementation", |
| } |
| VARIABLE.setParseAction(lambda s, l, t: Variable(ALIASES.get(t[0], t[0]))) |
| |
| VERSION_CMP = ( |
| L("===") | L("==") | L(">=") | L("<=") | L("!=") | L("~=") | L(">") | L("<") |
| ) |
| |
| MARKER_OP = VERSION_CMP | L("not in") | L("in") |
| MARKER_OP.setParseAction(lambda s, l, t: Op(t[0])) |
| |
| MARKER_VALUE = QuotedString("'") | QuotedString('"') |
| MARKER_VALUE.setParseAction(lambda s, l, t: Value(t[0])) |
| |
| BOOLOP = L("and") | L("or") |
| |
| MARKER_VAR = VARIABLE | MARKER_VALUE |
| |
| MARKER_ITEM = Group(MARKER_VAR + MARKER_OP + MARKER_VAR) |
| MARKER_ITEM.setParseAction(lambda s, l, t: tuple(t[0])) |
| |
| LPAREN = L("(").suppress() |
| RPAREN = L(")").suppress() |
| |
| MARKER_EXPR = Forward() |
| MARKER_ATOM = MARKER_ITEM | Group(LPAREN + MARKER_EXPR + RPAREN) |
| MARKER_EXPR << MARKER_ATOM + ZeroOrMore(BOOLOP + MARKER_EXPR) |
| |
| MARKER = stringStart + MARKER_EXPR + stringEnd |
| |
| |
| def _coerce_parse_result(results: Union[ParseResults, List[Any]]) -> List[Any]: |
| if isinstance(results, ParseResults): |
| return [_coerce_parse_result(i) for i in results] |
| else: |
| return results |
| |
| |
| def _format_marker( |
| marker: Union[List[str], Tuple[Node, ...], str], first: Optional[bool] = True |
| ) -> str: |
| |
| assert isinstance(marker, (list, tuple, str)) |
| |
| # Sometimes we have a structure like [[...]] which is a single item list |
| # where the single item is itself it's own list. In that case we want skip |
| # the rest of this function so that we don't get extraneous () on the |
| # outside. |
| if ( |
| isinstance(marker, list) |
| and len(marker) == 1 |
| and isinstance(marker[0], (list, tuple)) |
| ): |
| return _format_marker(marker[0]) |
| |
| if isinstance(marker, list): |
| inner = (_format_marker(m, first=False) for m in marker) |
| if first: |
| return " ".join(inner) |
| else: |
| return "(" + " ".join(inner) + ")" |
| elif isinstance(marker, tuple): |
| return " ".join([m.serialize() for m in marker]) |
| else: |
| return marker |
| |
| |
| _operators: Dict[str, Operator] = { |
| "in": lambda lhs, rhs: lhs in rhs, |
| "not in": lambda lhs, rhs: lhs not in rhs, |
| "<": operator.lt, |
| "<=": operator.le, |
| "==": operator.eq, |
| "!=": operator.ne, |
| ">=": operator.ge, |
| ">": operator.gt, |
| } |
| |
| |
| def _eval_op(lhs: str, op: Op, rhs: str) -> bool: |
| try: |
| spec = Specifier("".join([op.serialize(), rhs])) |
| except InvalidSpecifier: |
| pass |
| else: |
| return spec.contains(lhs) |
| |
| oper: Optional[Operator] = _operators.get(op.serialize()) |
| if oper is None: |
| raise UndefinedComparison(f"Undefined {op!r} on {lhs!r} and {rhs!r}.") |
| |
| return oper(lhs, rhs) |
| |
| |
| class Undefined: |
| pass |
| |
| |
| _undefined = Undefined() |
| |
| |
| def _get_env(environment: Dict[str, str], name: str) -> str: |
| value: Union[str, Undefined] = environment.get(name, _undefined) |
| |
| if isinstance(value, Undefined): |
| raise UndefinedEnvironmentName( |
| f"{name!r} does not exist in evaluation environment." |
| ) |
| |
| return value |
| |
| |
| def _evaluate_markers(markers: List[Any], environment: Dict[str, str]) -> bool: |
| groups: List[List[bool]] = [[]] |
| |
| for marker in markers: |
| assert isinstance(marker, (list, tuple, str)) |
| |
| if isinstance(marker, list): |
| groups[-1].append(_evaluate_markers(marker, environment)) |
| elif isinstance(marker, tuple): |
| lhs, op, rhs = marker |
| |
| if isinstance(lhs, Variable): |
| lhs_value = _get_env(environment, lhs.value) |
| rhs_value = rhs.value |
| else: |
| lhs_value = lhs.value |
| rhs_value = _get_env(environment, rhs.value) |
| |
| groups[-1].append(_eval_op(lhs_value, op, rhs_value)) |
| else: |
| assert marker in ["and", "or"] |
| if marker == "or": |
| groups.append([]) |
| |
| return any(all(item) for item in groups) |
| |
| |
| def format_full_version(info: "sys._version_info") -> str: |
| version = "{0.major}.{0.minor}.{0.micro}".format(info) |
| kind = info.releaselevel |
| if kind != "final": |
| version += kind[0] + str(info.serial) |
| return version |
| |
| |
| def default_environment() -> Dict[str, str]: |
| iver = format_full_version(sys.implementation.version) |
| implementation_name = sys.implementation.name |
| return { |
| "implementation_name": implementation_name, |
| "implementation_version": iver, |
| "os_name": os.name, |
| "platform_machine": platform.machine(), |
| "platform_release": platform.release(), |
| "platform_system": platform.system(), |
| "platform_version": platform.version(), |
| "python_full_version": platform.python_version(), |
| "platform_python_implementation": platform.python_implementation(), |
| "python_version": ".".join(platform.python_version_tuple()[:2]), |
| "sys_platform": sys.platform, |
| } |
| |
| |
| class Marker: |
| def __init__(self, marker: str) -> None: |
| try: |
| self._markers = _coerce_parse_result(MARKER.parseString(marker)) |
| except ParseException as e: |
| raise InvalidMarker( |
| f"Invalid marker: {marker!r}, parse error at " |
| f"{marker[e.loc : e.loc + 8]!r}" |
| ) |
| |
| def __str__(self) -> str: |
| return _format_marker(self._markers) |
| |
| def __repr__(self) -> str: |
| return f"<Marker('{self}')>" |
| |
| def evaluate(self, environment: Optional[Dict[str, str]] = None) -> bool: |
| """Evaluate a marker. |
| |
| Return the boolean from evaluating the given marker against the |
| environment. environment is an optional argument to override all or |
| part of the determined environment. |
| |
| The environment is determined from the current Python process. |
| """ |
| current_environment = default_environment() |
| if environment is not None: |
| current_environment.update(environment) |
| |
| return _evaluate_markers(self._markers, current_environment) |
