summaryrefslogtreecommitdiff
path: root/src/pip/_internal/resolution/resolvelib/requirements.py
blob: b4cb571401ef2e50295856197bbd8ba1852e8f98 (plain)
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
from pip._vendor.packaging.specifiers import SpecifierSet
from pip._vendor.packaging.utils import NormalizedName, canonicalize_name

from pip._internal.req.req_install import InstallRequirement

from .base import Candidate, CandidateLookup, Requirement, format_name


class ExplicitRequirement(Requirement):
    def __init__(self, candidate):
        # type: (Candidate) -> None
        self.candidate = candidate

    def __str__(self):
        # type: () -> str
        return str(self.candidate)

    def __repr__(self):
        # type: () -> str
        return "{class_name}({candidate!r})".format(
            class_name=self.__class__.__name__,
            candidate=self.candidate,
        )

    @property
    def project_name(self):
        # type: () -> NormalizedName
        # No need to canonicalise - the candidate did this
        return self.candidate.project_name

    @property
    def name(self):
        # type: () -> str
        # No need to canonicalise - the candidate did this
        return self.candidate.name

    def format_for_error(self):
        # type: () -> str
        return self.candidate.format_for_error()

    def get_candidate_lookup(self):
        # type: () -> CandidateLookup
        return self.candidate, None

    def is_satisfied_by(self, candidate):
        # type: (Candidate) -> bool
        return candidate == self.candidate


class SpecifierRequirement(Requirement):
    def __init__(self, ireq):
        # type: (InstallRequirement) -> None
        assert ireq.link is None, "This is a link, not a specifier"
        self._ireq = ireq
        self._extras = frozenset(ireq.extras)

    def __str__(self):
        # type: () -> str
        return str(self._ireq.req)

    def __repr__(self):
        # type: () -> str
        return "{class_name}({requirement!r})".format(
            class_name=self.__class__.__name__,
            requirement=str(self._ireq.req),
        )

    @property
    def project_name(self):
        # type: () -> NormalizedName
        assert self._ireq.req, "Specifier-backed ireq is always PEP 508"
        return canonicalize_name(self._ireq.req.name)

    @property
    def name(self):
        # type: () -> str
        return format_name(self.project_name, self._extras)

    def format_for_error(self):
        # type: () -> str

        # Convert comma-separated specifiers into "A, B, ..., F and G"
        # This makes the specifier a bit more "human readable", without
        # risking a change in meaning. (Hopefully! Not all edge cases have
        # been checked)
        parts = [s.strip() for s in str(self).split(",")]
        if len(parts) == 0:
            return ""
        elif len(parts) == 1:
            return parts[0]

        return ", ".join(parts[:-1]) + " and " + parts[-1]

    def get_candidate_lookup(self):
        # type: () -> CandidateLookup
        return None, self._ireq

    def is_satisfied_by(self, candidate):
        # type: (Candidate) -> bool
        assert candidate.name == self.name, (
            f"Internal issue: Candidate is not for this requirement "
            f"{candidate.name} vs {self.name}"
        )
        # We can safely always allow prereleases here since PackageFinder
        # already implements the prerelease logic, and would have filtered out
        # prerelease candidates if the user does not expect them.
        assert self._ireq.req, "Specifier-backed ireq is always PEP 508"
        spec = self._ireq.req.specifier
        return spec.contains(candidate.version, prereleases=True)


class RequiresPythonRequirement(Requirement):
    """A requirement representing Requires-Python metadata."""

    def __init__(self, specifier, match):
        # type: (SpecifierSet, Candidate) -> None
        self.specifier = specifier
        self._candidate = match

    def __str__(self):
        # type: () -> str
        return f"Python {self.specifier}"

    def __repr__(self):
        # type: () -> str
        return "{class_name}({specifier!r})".format(
            class_name=self.__class__.__name__,
            specifier=str(self.specifier),
        )

    @property
    def project_name(self):
        # type: () -> NormalizedName
        return self._candidate.project_name

    @property
    def name(self):
        # type: () -> str
        return self._candidate.name

    def format_for_error(self):
        # type: () -> str
        return str(self)

    def get_candidate_lookup(self):
        # type: () -> CandidateLookup
        if self.specifier.contains(self._candidate.version, prereleases=True):
            return self._candidate, None
        return None, None

    def is_satisfied_by(self, candidate):
        # type: (Candidate) -> bool
        assert candidate.name == self._candidate.name, "Not Python candidate"
        # We can safely always allow prereleases here since PackageFinder
        # already implements the prerelease logic, and would have filtered out
        # prerelease candidates if the user does not expect them.
        return self.specifier.contains(candidate.version, prereleases=True)


class UnsatisfiableRequirement(Requirement):
    """A requirement that cannot be satisfied."""

    def __init__(self, name):
        # type: (NormalizedName) -> None
        self._name = name

    def __str__(self):
        # type: () -> str
        return "{} (unavailable)".format(self._name)

    def __repr__(self):
        # type: () -> str
        return "{class_name}({name!r})".format(
            class_name=self.__class__.__name__,
            name=str(self._name),
        )

    @property
    def project_name(self):
        # type: () -> NormalizedName
        return self._name

    @property
    def name(self):
        # type: () -> str
        return self._name

    def format_for_error(self):
        # type: () -> str
        return str(self)

    def get_candidate_lookup(self):
        # type: () -> CandidateLookup
        return None, None

    def is_satisfied_by(self, candidate):
        # type: (Candidate) -> bool
        return False