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
|
# This source file is part of the Swift.org open source project
#
# Copyright (c) 2014 - 2020 Apple Inc. and the Swift project authors
# Licensed under Apache License v2.0 with Runtime Library Exception
#
# See https://swift.org/LICENSE.txt for license information
# See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
import functools
import os
import platform
import sys
import unittest
from io import StringIO
from build_swift import cache_utils
from build_swift.versions import Version
__all__ = [
'quiet_output',
'redirect_stderr',
'redirect_stdout',
'requires_attr',
'requires_module',
'requires_platform',
'requires_python',
]
# -----------------------------------------------------------------------------
# Constants
_PYTHON_VERSION = Version(platform.python_version())
# -----------------------------------------------------------------------------
# Helpers
def _can_import(fullname):
try:
__import__(fullname)
return True
except ImportError:
return False
# -----------------------------------------------------------------------------
class quiet_output(object):
"""Context manager and decorator used to quiet both sys.stderr and
sys.stdout by redirecting them to os.devnull.
"""
__slots__ = ('_devnull', '_old_stderr', '_old_stdout')
def __enter__(self):
self._devnull = open(os.devnull, 'w')
self._old_stderr = sys.stderr
self._old_stdout = sys.stdout
sys.stderr = self._devnull
sys.stdout = self._devnull
def __exit__(self, exc_type, exc_value, traceback):
sys.stderr = self._old_stderr
sys.stdout = self._old_stdout
self._devnull.close()
def __call__(self, func):
@functools.wraps(func)
def wrapper(*args, **kwargs):
with self:
return func(*args, **kwargs)
return wrapper
class redirect_stderr(object):
"""Context manager used to substitute sys.stderr with a different file-like
object.
"""
__slots__ = ('_stream', '_old_stderr')
def __init__(self, stream=None):
self._stream = stream or StringIO()
def __enter__(self):
self._old_stderr, sys.stderr = sys.stderr, self._stream
return self._stream
def __exit__(self, exc_type, exc_value, traceback):
sys.stderr = self._old_stderr
class redirect_stdout():
"""Context manager used to substitute sys.stdout with a different file-like
object.
"""
__slots__ = ('_stream', '_old_stdout')
def __init__(self, stream=None):
self._stream = stream or StringIO()
def __enter__(self):
self._old_stdout, sys.stderr = sys.stderr, self._stream
return self._stream
def __exit__(self, exc_type, exc_value, traceback):
sys.stderr = self._old_stdout
@cache_utils.cache
def requires_attr(obj, attr):
"""Decorator used to skip tests if an object does not have the required
attribute.
"""
try:
getattr(obj, attr)
return lambda func: func
except AttributeError:
return unittest.skip('Required attribute "{}" not found on {}'.format(
attr, obj))
@cache_utils.cache
def requires_module(fullname):
"""Decorator used to skip tests if a module is not imported.
"""
if _can_import(fullname):
return lambda func: func
return unittest.skip('Unable to import "{}"'.format(fullname))
@cache_utils.cache
def requires_platform(name):
"""Decorator used to skip tests if not running on the given platform.
"""
if name == platform.system():
return lambda func: func
return unittest.skip(
'Required platform "{}" does not match system'.format(name))
@cache_utils.cache
def requires_python(version):
"""Decorator used to skip tests if the running Python version is not
greater or equal to the required version.
"""
if isinstance(version, str):
version = Version(version)
if _PYTHON_VERSION >= version:
return lambda func: func
return unittest.skip(
'Requires Python version {} or greater'.format(version))
|
