File size: 10,671 Bytes
6370773 |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 |
# 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 annotations
import operator
import os
import platform
import sys
from typing import Any, Callable, TypedDict, cast
from ._parser import MarkerAtom, MarkerList, Op, Value, Variable
from ._parser import parse_marker as _parse_marker
from ._tokenizer import ParserSyntaxError
from .specifiers import InvalidSpecifier, Specifier
from .utils import canonicalize_name
__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 Environment(TypedDict):
implementation_name: str
"""The implementation's identifier, e.g. ``'cpython'``."""
implementation_version: str
"""
The implementation's version, e.g. ``'3.13.0a2'`` for CPython 3.13.0a2, or
``'7.3.13'`` for PyPy3.10 v7.3.13.
"""
os_name: str
"""
The value of :py:data:`os.name`. The name of the operating system dependent module
imported, e.g. ``'posix'``.
"""
platform_machine: str
"""
Returns the machine type, e.g. ``'i386'``.
An empty string if the value cannot be determined.
"""
platform_release: str
"""
The system's release, e.g. ``'2.2.0'`` or ``'NT'``.
An empty string if the value cannot be determined.
"""
platform_system: str
"""
The system/OS name, e.g. ``'Linux'``, ``'Windows'`` or ``'Java'``.
An empty string if the value cannot be determined.
"""
platform_version: str
"""
The system's release version, e.g. ``'#3 on degas'``.
An empty string if the value cannot be determined.
"""
python_full_version: str
"""
The Python version as string ``'major.minor.patchlevel'``.
Note that unlike the Python :py:data:`sys.version`, this value will always include
the patchlevel (it defaults to 0).
"""
platform_python_implementation: str
"""
A string identifying the Python implementation, e.g. ``'CPython'``.
"""
python_version: str
"""The Python version as string ``'major.minor'``."""
sys_platform: str
"""
This string contains a platform identifier that can be used to append
platform-specific components to :py:data:`sys.path`, for instance.
For Unix systems, except on Linux and AIX, this is the lowercased OS name as
returned by ``uname -s`` with the first part of the version as returned by
``uname -r`` appended, e.g. ``'sunos5'`` or ``'freebsd8'``, at the time when Python
was built.
"""
def _normalize_extra_values(results: Any) -> Any:
"""
Normalize extra values.
"""
if isinstance(results[0], tuple):
lhs, op, rhs = results[0]
if isinstance(lhs, Variable) and lhs.value == "extra":
normalized_extra = canonicalize_name(rhs.value)
rhs = Value(normalized_extra)
elif isinstance(rhs, Variable) and rhs.value == "extra":
normalized_extra = canonicalize_name(lhs.value)
lhs = Value(normalized_extra)
results[0] = lhs, op, rhs
return results
def _format_marker(
marker: list[str] | MarkerAtom | str, first: bool | None = 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, prereleases=True)
oper: Operator | None = _operators.get(op.serialize())
if oper is None:
raise UndefinedComparison(f"Undefined {op!r} on {lhs!r} and {rhs!r}.")
return oper(lhs, rhs)
def _normalize(*values: str, key: str) -> tuple[str, ...]:
# PEP 685 – Comparison of extra names for optional distribution dependencies
# https://peps.python.org/pep-0685/
# > When comparing extra names, tools MUST normalize the names being
# > compared using the semantics outlined in PEP 503 for names
if key == "extra":
return tuple(canonicalize_name(v) for v in values)
# other environment markers don't have such standards
return values
def _evaluate_markers(markers: MarkerList, 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):
environment_key = lhs.value
lhs_value = environment[environment_key]
rhs_value = rhs.value
else:
lhs_value = lhs.value
environment_key = rhs.value
rhs_value = environment[environment_key]
lhs_value, rhs_value = _normalize(lhs_value, rhs_value, key=environment_key)
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() -> Environment:
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:
# Note: We create a Marker object without calling this constructor in
# packaging.requirements.Requirement. If any additional logic is
# added here, make sure to mirror/adapt Requirement.
try:
self._markers = _normalize_extra_values(_parse_marker(marker))
# The attribute `_markers` can be described in terms of a recursive type:
# MarkerList = List[Union[Tuple[Node, ...], str, MarkerList]]
#
# For example, the following expression:
# python_version > "3.6" or (python_version == "3.6" and os_name == "unix")
#
# is parsed into:
# [
# (<Variable('python_version')>, <Op('>')>, <Value('3.6')>),
# 'and',
# [
# (<Variable('python_version')>, <Op('==')>, <Value('3.6')>),
# 'or',
# (<Variable('os_name')>, <Op('==')>, <Value('unix')>)
# ]
# ]
except ParserSyntaxError as e:
raise InvalidMarker(str(e)) from e
def __str__(self) -> str:
return _format_marker(self._markers)
def __repr__(self) -> str:
return f"<Marker('{self}')>"
def __hash__(self) -> int:
return hash((self.__class__.__name__, str(self)))
def __eq__(self, other: Any) -> bool:
if not isinstance(other, Marker):
return NotImplemented
return str(self) == str(other)
def evaluate(self, environment: dict[str, str] | None = 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 = cast("dict[str, str]", default_environment())
current_environment["extra"] = ""
# Work around platform.python_version() returning something that is not PEP 440
# compliant for non-tagged Python builds. We preserve default_environment()'s
# behavior of returning platform.python_version() verbatim, and leave it to the
# caller to provide a syntactically valid version if they want to override it.
if current_environment["python_full_version"].endswith("+"):
current_environment["python_full_version"] += "local"
if environment is not None:
current_environment.update(environment)
# The API used to allow setting extra to None. We need to handle this
# case for backwards compatibility.
if current_environment["extra"] is None:
current_environment["extra"] = ""
return _evaluate_markers(self._markers, current_environment)
|