Coverage for /home/martinb/.local/share/virtualenvs/camcops/lib/python3.6/site-packages/pkg_resources/_vendor/packaging/markers.py : 44%

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1# This file is dual licensed under the terms of the Apache License, Version
2# 2.0, and the BSD License. See the LICENSE file in the root of this repository
3# for complete details.
4from __future__ import absolute_import, division, print_function
6import operator
7import os
8import platform
9import sys
11from pkg_resources.extern.pyparsing import ParseException, ParseResults, stringStart, stringEnd
12from pkg_resources.extern.pyparsing import ZeroOrMore, Group, Forward, QuotedString
13from pkg_resources.extern.pyparsing import Literal as L # noqa
15from ._compat import string_types
16from .specifiers import Specifier, InvalidSpecifier
19__all__ = [
20 "InvalidMarker", "UndefinedComparison", "UndefinedEnvironmentName",
21 "Marker", "default_environment",
22]
25class InvalidMarker(ValueError):
26 """
27 An invalid marker was found, users should refer to PEP 508.
28 """
31class UndefinedComparison(ValueError):
32 """
33 An invalid operation was attempted on a value that doesn't support it.
34 """
37class UndefinedEnvironmentName(ValueError):
38 """
39 A name was attempted to be used that does not exist inside of the
40 environment.
41 """
44class Node(object):
46 def __init__(self, value):
47 self.value = value
49 def __str__(self):
50 return str(self.value)
52 def __repr__(self):
53 return "<{0}({1!r})>".format(self.__class__.__name__, str(self))
55 def serialize(self):
56 raise NotImplementedError
59class Variable(Node):
61 def serialize(self):
62 return str(self)
65class Value(Node):
67 def serialize(self):
68 return '"{0}"'.format(self)
71class Op(Node):
73 def serialize(self):
74 return str(self)
77VARIABLE = (
78 L("implementation_version") |
79 L("platform_python_implementation") |
80 L("implementation_name") |
81 L("python_full_version") |
82 L("platform_release") |
83 L("platform_version") |
84 L("platform_machine") |
85 L("platform_system") |
86 L("python_version") |
87 L("sys_platform") |
88 L("os_name") |
89 L("os.name") | # PEP-345
90 L("sys.platform") | # PEP-345
91 L("platform.version") | # PEP-345
92 L("platform.machine") | # PEP-345
93 L("platform.python_implementation") | # PEP-345
94 L("python_implementation") | # undocumented setuptools legacy
95 L("extra")
96)
97ALIASES = {
98 'os.name': 'os_name',
99 'sys.platform': 'sys_platform',
100 'platform.version': 'platform_version',
101 'platform.machine': 'platform_machine',
102 'platform.python_implementation': 'platform_python_implementation',
103 'python_implementation': 'platform_python_implementation'
104}
105VARIABLE.setParseAction(lambda s, l, t: Variable(ALIASES.get(t[0], t[0])))
107VERSION_CMP = (
108 L("===") |
109 L("==") |
110 L(">=") |
111 L("<=") |
112 L("!=") |
113 L("~=") |
114 L(">") |
115 L("<")
116)
118MARKER_OP = VERSION_CMP | L("not in") | L("in")
119MARKER_OP.setParseAction(lambda s, l, t: Op(t[0]))
121MARKER_VALUE = QuotedString("'") | QuotedString('"')
122MARKER_VALUE.setParseAction(lambda s, l, t: Value(t[0]))
124BOOLOP = L("and") | L("or")
126MARKER_VAR = VARIABLE | MARKER_VALUE
128MARKER_ITEM = Group(MARKER_VAR + MARKER_OP + MARKER_VAR)
129MARKER_ITEM.setParseAction(lambda s, l, t: tuple(t[0]))
131LPAREN = L("(").suppress()
132RPAREN = L(")").suppress()
134MARKER_EXPR = Forward()
135MARKER_ATOM = MARKER_ITEM | Group(LPAREN + MARKER_EXPR + RPAREN)
136MARKER_EXPR << MARKER_ATOM + ZeroOrMore(BOOLOP + MARKER_EXPR)
138MARKER = stringStart + MARKER_EXPR + stringEnd
141def _coerce_parse_result(results):
142 if isinstance(results, ParseResults):
143 return [_coerce_parse_result(i) for i in results]
144 else:
145 return results
148def _format_marker(marker, first=True):
149 assert isinstance(marker, (list, tuple, string_types))
151 # Sometimes we have a structure like [[...]] which is a single item list
152 # where the single item is itself it's own list. In that case we want skip
153 # the rest of this function so that we don't get extraneous () on the
154 # outside.
155 if (isinstance(marker, list) and len(marker) == 1 and
156 isinstance(marker[0], (list, tuple))):
157 return _format_marker(marker[0])
159 if isinstance(marker, list):
160 inner = (_format_marker(m, first=False) for m in marker)
161 if first:
162 return " ".join(inner)
163 else:
164 return "(" + " ".join(inner) + ")"
165 elif isinstance(marker, tuple):
166 return " ".join([m.serialize() for m in marker])
167 else:
168 return marker
171_operators = {
172 "in": lambda lhs, rhs: lhs in rhs,
173 "not in": lambda lhs, rhs: lhs not in rhs,
174 "<": operator.lt,
175 "<=": operator.le,
176 "==": operator.eq,
177 "!=": operator.ne,
178 ">=": operator.ge,
179 ">": operator.gt,
180}
183def _eval_op(lhs, op, rhs):
184 try:
185 spec = Specifier("".join([op.serialize(), rhs]))
186 except InvalidSpecifier:
187 pass
188 else:
189 return spec.contains(lhs)
191 oper = _operators.get(op.serialize())
192 if oper is None:
193 raise UndefinedComparison(
194 "Undefined {0!r} on {1!r} and {2!r}.".format(op, lhs, rhs)
195 )
197 return oper(lhs, rhs)
200_undefined = object()
203def _get_env(environment, name):
204 value = environment.get(name, _undefined)
206 if value is _undefined:
207 raise UndefinedEnvironmentName(
208 "{0!r} does not exist in evaluation environment.".format(name)
209 )
211 return value
214def _evaluate_markers(markers, environment):
215 groups = [[]]
217 for marker in markers:
218 assert isinstance(marker, (list, tuple, string_types))
220 if isinstance(marker, list):
221 groups[-1].append(_evaluate_markers(marker, environment))
222 elif isinstance(marker, tuple):
223 lhs, op, rhs = marker
225 if isinstance(lhs, Variable):
226 lhs_value = _get_env(environment, lhs.value)
227 rhs_value = rhs.value
228 else:
229 lhs_value = lhs.value
230 rhs_value = _get_env(environment, rhs.value)
232 groups[-1].append(_eval_op(lhs_value, op, rhs_value))
233 else:
234 assert marker in ["and", "or"]
235 if marker == "or":
236 groups.append([])
238 return any(all(item) for item in groups)
241def format_full_version(info):
242 version = '{0.major}.{0.minor}.{0.micro}'.format(info)
243 kind = info.releaselevel
244 if kind != 'final':
245 version += kind[0] + str(info.serial)
246 return version
249def default_environment():
250 if hasattr(sys, 'implementation'):
251 iver = format_full_version(sys.implementation.version)
252 implementation_name = sys.implementation.name
253 else:
254 iver = '0'
255 implementation_name = ''
257 return {
258 "implementation_name": implementation_name,
259 "implementation_version": iver,
260 "os_name": os.name,
261 "platform_machine": platform.machine(),
262 "platform_release": platform.release(),
263 "platform_system": platform.system(),
264 "platform_version": platform.version(),
265 "python_full_version": platform.python_version(),
266 "platform_python_implementation": platform.python_implementation(),
267 "python_version": platform.python_version()[:3],
268 "sys_platform": sys.platform,
269 }
272class Marker(object):
274 def __init__(self, marker):
275 try:
276 self._markers = _coerce_parse_result(MARKER.parseString(marker))
277 except ParseException as e:
278 err_str = "Invalid marker: {0!r}, parse error at {1!r}".format(
279 marker, marker[e.loc:e.loc + 8])
280 raise InvalidMarker(err_str)
282 def __str__(self):
283 return _format_marker(self._markers)
285 def __repr__(self):
286 return "<Marker({0!r})>".format(str(self))
288 def evaluate(self, environment=None):
289 """Evaluate a marker.
291 Return the boolean from evaluating the given marker against the
292 environment. environment is an optional argument to override all or
293 part of the determined environment.
295 The environment is determined from the current Python process.
296 """
297 current_environment = default_environment()
298 if environment is not None:
299 current_environment.update(environment)
301 return _evaluate_markers(self._markers, current_environment)