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Diffstat (limited to 'pkg_resources/_vendor/packaging/markers.py')
| -rw-r--r-- | pkg_resources/_vendor/packaging/markers.py | 301 |
1 files changed, 301 insertions, 0 deletions
diff --git a/pkg_resources/_vendor/packaging/markers.py b/pkg_resources/_vendor/packaging/markers.py new file mode 100644 index 0000000..892e578 --- /dev/null +++ b/pkg_resources/_vendor/packaging/markers.py @@ -0,0 +1,301 @@ +# 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. +from __future__ import absolute_import, division, print_function + +import operator +import os +import platform +import sys + +from pkg_resources.extern.pyparsing import ParseException, ParseResults, stringStart, stringEnd +from pkg_resources.extern.pyparsing import ZeroOrMore, Group, Forward, QuotedString +from pkg_resources.extern.pyparsing import Literal as L # noqa + +from ._compat import string_types +from .specifiers import Specifier, InvalidSpecifier + + +__all__ = [ + "InvalidMarker", "UndefinedComparison", "UndefinedEnvironmentName", + "Marker", "default_environment", +] + + +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(object): + + def __init__(self, value): + self.value = value + + def __str__(self): + return str(self.value) + + def __repr__(self): + return "<{0}({1!r})>".format(self.__class__.__name__, str(self)) + + def serialize(self): + raise NotImplementedError + + +class Variable(Node): + + def serialize(self): + return str(self) + + +class Value(Node): + + def serialize(self): + return '"{0}"'.format(self) + + +class Op(Node): + + def serialize(self): + 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") +) +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): + if isinstance(results, ParseResults): + return [_coerce_parse_result(i) for i in results] + else: + return results + + +def _format_marker(marker, first=True): + assert isinstance(marker, (list, tuple, string_types)) + + # 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 = { + "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, op, rhs): + try: + spec = Specifier("".join([op.serialize(), rhs])) + except InvalidSpecifier: + pass + else: + return spec.contains(lhs) + + oper = _operators.get(op.serialize()) + if oper is None: + raise UndefinedComparison( + "Undefined {0!r} on {1!r} and {2!r}.".format(op, lhs, rhs) + ) + + return oper(lhs, rhs) + + +_undefined = object() + + +def _get_env(environment, name): + value = environment.get(name, _undefined) + + if value is _undefined: + raise UndefinedEnvironmentName( + "{0!r} does not exist in evaluation environment.".format(name) + ) + + return value + + +def _evaluate_markers(markers, environment): + groups = [[]] + + for marker in markers: + assert isinstance(marker, (list, tuple, string_types)) + + 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): + 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(): + if hasattr(sys, 'implementation'): + iver = format_full_version(sys.implementation.version) + implementation_name = sys.implementation.name + else: + iver = '0' + 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": platform.python_version()[:3], + "sys_platform": sys.platform, + } + + +class Marker(object): + + def __init__(self, marker): + try: + self._markers = _coerce_parse_result(MARKER.parseString(marker)) + except ParseException as e: + err_str = "Invalid marker: {0!r}, parse error at {1!r}".format( + marker, marker[e.loc:e.loc + 8]) + raise InvalidMarker(err_str) + + def __str__(self): + return _format_marker(self._markers) + + def __repr__(self): + return "<Marker({0!r})>".format(str(self)) + + def evaluate(self, environment=None): + """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) |