Python code coverage for Lib/test/libregrtest/save_env.py

#	count	content
1	n/a	import builtins
2	n/a	import locale
3	n/a	import logging
4	n/a	import os
5	n/a	import shutil
6	n/a	import sys
7	n/a	import sysconfig
8	n/a	import warnings
9	n/a	from test import support
10	n/a	try:
11	n/a	import threading
12	n/a	except ImportError:
13	n/a	threading = None
14	n/a	try:
15	n/a	import _multiprocessing, multiprocessing.process
16	n/a	except ImportError:
17	n/a	multiprocessing = None
18	n/a
19	n/a
20	n/a	# Unit tests are supposed to leave the execution environment unchanged
21	n/a	# once they complete. But sometimes tests have bugs, especially when
22	n/a	# tests fail, and the changes to environment go on to mess up other
23	n/a	# tests. This can cause issues with buildbot stability, since tests
24	n/a	# are run in random order and so problems may appear to come and go.
25	n/a	# There are a few things we can save and restore to mitigate this, and
26	n/a	# the following context manager handles this task.
27	n/a
28	n/a	class saved_test_environment:
29	n/a	"""Save bits of the test environment and restore them at block exit.
30	n/a
31	n/a	with saved_test_environment(testname, verbose, quiet):
32	n/a	#stuff
33	n/a
34	n/a	Unless quiet is True, a warning is printed to stderr if any of
35	n/a	the saved items was changed by the test. The attribute 'changed'
36	n/a	is initially False, but is set to True if a change is detected.
37	n/a
38	n/a	If verbose is more than 1, the before and after state of changed
39	n/a	items is also printed.
40	n/a	"""
41	n/a
42	n/a	changed = False
43	n/a
44	n/a	def __init__(self, testname, verbose=0, quiet=False, *, pgo=False):
45	n/a	self.testname = testname
46	n/a	self.verbose = verbose
47	n/a	self.quiet = quiet
48	n/a	self.pgo = pgo
49	n/a
50	n/a	# To add things to save and restore, add a name XXX to the resources list
51	n/a	# and add corresponding get_XXX/restore_XXX functions. get_XXX should
52	n/a	# return the value to be saved and compared against a second call to the
53	n/a	# get function when test execution completes. restore_XXX should accept
54	n/a	# the saved value and restore the resource using it. It will be called if
55	n/a	# and only if a change in the value is detected.
56	n/a	#
57	n/a	# Note: XXX will have any '.' replaced with '_' characters when determining
58	n/a	# the corresponding method names.
59	n/a
60	n/a	resources = ('sys.argv', 'cwd', 'sys.stdin', 'sys.stdout', 'sys.stderr',
61	n/a	'os.environ', 'sys.path', 'sys.path_hooks', '__import__',
62	n/a	'warnings.filters', 'asyncore.socket_map',
63	n/a	'logging._handlers', 'logging._handlerList', 'sys.gettrace',
64	n/a	'sys.warnoptions',
65	n/a	# multiprocessing.process._cleanup() may release ref
66	n/a	# to a thread, so check processes first.
67	n/a	'multiprocessing.process._dangling', 'threading._dangling',
68	n/a	'sysconfig._CONFIG_VARS', 'sysconfig._INSTALL_SCHEMES',
69	n/a	'files', 'locale', 'warnings.showwarning',
70	n/a	'shutil_archive_formats', 'shutil_unpack_formats',
71	n/a	)
72	n/a
73	n/a	def get_sys_argv(self):
74	n/a	return id(sys.argv), sys.argv, sys.argv[:]
75	n/a	def restore_sys_argv(self, saved_argv):
76	n/a	sys.argv = saved_argv[1]
77	n/a	sys.argv[:] = saved_argv[2]
78	n/a
79	n/a	def get_cwd(self):
80	n/a	return os.getcwd()
81	n/a	def restore_cwd(self, saved_cwd):
82	n/a	os.chdir(saved_cwd)
83	n/a
84	n/a	def get_sys_stdout(self):
85	n/a	return sys.stdout
86	n/a	def restore_sys_stdout(self, saved_stdout):
87	n/a	sys.stdout = saved_stdout
88	n/a
89	n/a	def get_sys_stderr(self):
90	n/a	return sys.stderr
91	n/a	def restore_sys_stderr(self, saved_stderr):
92	n/a	sys.stderr = saved_stderr
93	n/a
94	n/a	def get_sys_stdin(self):
95	n/a	return sys.stdin
96	n/a	def restore_sys_stdin(self, saved_stdin):
97	n/a	sys.stdin = saved_stdin
98	n/a
99	n/a	def get_os_environ(self):
100	n/a	return id(os.environ), os.environ, dict(os.environ)
101	n/a	def restore_os_environ(self, saved_environ):
102	n/a	os.environ = saved_environ[1]
103	n/a	os.environ.clear()
104	n/a	os.environ.update(saved_environ[2])
105	n/a
106	n/a	def get_sys_path(self):
107	n/a	return id(sys.path), sys.path, sys.path[:]
108	n/a	def restore_sys_path(self, saved_path):
109	n/a	sys.path = saved_path[1]
110	n/a	sys.path[:] = saved_path[2]
111	n/a
112	n/a	def get_sys_path_hooks(self):
113	n/a	return id(sys.path_hooks), sys.path_hooks, sys.path_hooks[:]
114	n/a	def restore_sys_path_hooks(self, saved_hooks):
115	n/a	sys.path_hooks = saved_hooks[1]
116	n/a	sys.path_hooks[:] = saved_hooks[2]
117	n/a
118	n/a	def get_sys_gettrace(self):
119	n/a	return sys.gettrace()
120	n/a	def restore_sys_gettrace(self, trace_fxn):
121	n/a	sys.settrace(trace_fxn)
122	n/a
123	n/a	def get___import__(self):
124	n/a	return builtins.__import__
125	n/a	def restore___import__(self, import_):
126	n/a	builtins.__import__ = import_
127	n/a
128	n/a	def get_warnings_filters(self):
129	n/a	return id(warnings.filters), warnings.filters, warnings.filters[:]
130	n/a	def restore_warnings_filters(self, saved_filters):
131	n/a	warnings.filters = saved_filters[1]
132	n/a	warnings.filters[:] = saved_filters[2]
133	n/a
134	n/a	def get_asyncore_socket_map(self):
135	n/a	asyncore = sys.modules.get('asyncore')
136	n/a	# XXX Making a copy keeps objects alive until __exit__ gets called.
137	n/a	return asyncore and asyncore.socket_map.copy() or {}
138	n/a	def restore_asyncore_socket_map(self, saved_map):
139	n/a	asyncore = sys.modules.get('asyncore')
140	n/a	if asyncore is not None:
141	n/a	asyncore.close_all(ignore_all=True)
142	n/a	asyncore.socket_map.update(saved_map)
143	n/a
144	n/a	def get_shutil_archive_formats(self):
145	n/a	# we could call get_archives_formats() but that only returns the
146	n/a	# registry keys; we want to check the values too (the functions that
147	n/a	# are registered)
148	n/a	return shutil._ARCHIVE_FORMATS, shutil._ARCHIVE_FORMATS.copy()
149	n/a	def restore_shutil_archive_formats(self, saved):
150	n/a	shutil._ARCHIVE_FORMATS = saved[0]
151	n/a	shutil._ARCHIVE_FORMATS.clear()
152	n/a	shutil._ARCHIVE_FORMATS.update(saved[1])
153	n/a
154	n/a	def get_shutil_unpack_formats(self):
155	n/a	return shutil._UNPACK_FORMATS, shutil._UNPACK_FORMATS.copy()
156	n/a	def restore_shutil_unpack_formats(self, saved):
157	n/a	shutil._UNPACK_FORMATS = saved[0]
158	n/a	shutil._UNPACK_FORMATS.clear()
159	n/a	shutil._UNPACK_FORMATS.update(saved[1])
160	n/a
161	n/a	def get_logging__handlers(self):
162	n/a	# _handlers is a WeakValueDictionary
163	n/a	return id(logging._handlers), logging._handlers, logging._handlers.copy()
164	n/a	def restore_logging__handlers(self, saved_handlers):
165	n/a	# Can't easily revert the logging state
166	n/a	pass
167	n/a
168	n/a	def get_logging__handlerList(self):
169	n/a	# _handlerList is a list of weakrefs to handlers
170	n/a	return id(logging._handlerList), logging._handlerList, logging._handlerList[:]
171	n/a	def restore_logging__handlerList(self, saved_handlerList):
172	n/a	# Can't easily revert the logging state
173	n/a	pass
174	n/a
175	n/a	def get_sys_warnoptions(self):
176	n/a	return id(sys.warnoptions), sys.warnoptions, sys.warnoptions[:]
177	n/a	def restore_sys_warnoptions(self, saved_options):
178	n/a	sys.warnoptions = saved_options[1]
179	n/a	sys.warnoptions[:] = saved_options[2]
180	n/a
181	n/a	# Controlling dangling references to Thread objects can make it easier
182	n/a	# to track reference leaks.
183	n/a	def get_threading__dangling(self):
184	n/a	if not threading:
185	n/a	return None
186	n/a	# This copies the weakrefs without making any strong reference
187	n/a	return threading._dangling.copy()
188	n/a	def restore_threading__dangling(self, saved):
189	n/a	if not threading:
190	n/a	return
191	n/a	threading._dangling.clear()
192	n/a	threading._dangling.update(saved)
193	n/a
194	n/a	# Same for Process objects
195	n/a	def get_multiprocessing_process__dangling(self):
196	n/a	if not multiprocessing:
197	n/a	return None
198	n/a	# Unjoined process objects can survive after process exits
199	n/a	multiprocessing.process._cleanup()
200	n/a	# This copies the weakrefs without making any strong reference
201	n/a	return multiprocessing.process._dangling.copy()
202	n/a	def restore_multiprocessing_process__dangling(self, saved):
203	n/a	if not multiprocessing:
204	n/a	return
205	n/a	multiprocessing.process._dangling.clear()
206	n/a	multiprocessing.process._dangling.update(saved)
207	n/a
208	n/a	def get_sysconfig__CONFIG_VARS(self):
209	n/a	# make sure the dict is initialized
210	n/a	sysconfig.get_config_var('prefix')
211	n/a	return (id(sysconfig._CONFIG_VARS), sysconfig._CONFIG_VARS,
212	n/a	dict(sysconfig._CONFIG_VARS))
213	n/a	def restore_sysconfig__CONFIG_VARS(self, saved):
214	n/a	sysconfig._CONFIG_VARS = saved[1]
215	n/a	sysconfig._CONFIG_VARS.clear()
216	n/a	sysconfig._CONFIG_VARS.update(saved[2])
217	n/a
218	n/a	def get_sysconfig__INSTALL_SCHEMES(self):
219	n/a	return (id(sysconfig._INSTALL_SCHEMES), sysconfig._INSTALL_SCHEMES,
220	n/a	sysconfig._INSTALL_SCHEMES.copy())
221	n/a	def restore_sysconfig__INSTALL_SCHEMES(self, saved):
222	n/a	sysconfig._INSTALL_SCHEMES = saved[1]
223	n/a	sysconfig._INSTALL_SCHEMES.clear()
224	n/a	sysconfig._INSTALL_SCHEMES.update(saved[2])
225	n/a
226	n/a	def get_files(self):
227	n/a	return sorted(fn + ('/' if os.path.isdir(fn) else '')
228	n/a	for fn in os.listdir())
229	n/a	def restore_files(self, saved_value):
230	n/a	fn = support.TESTFN
231	n/a	if fn not in saved_value and (fn + '/') not in saved_value:
232	n/a	if os.path.isfile(fn):
233	n/a	support.unlink(fn)
234	n/a	elif os.path.isdir(fn):
235	n/a	support.rmtree(fn)
236	n/a
237	n/a	_lc = [getattr(locale, lc) for lc in dir(locale)
238	n/a	if lc.startswith('LC_')]
239	n/a	def get_locale(self):
240	n/a	pairings = []
241	n/a	for lc in self._lc:
242	n/a	try:
243	n/a	pairings.append((lc, locale.setlocale(lc, None)))
244	n/a	except (TypeError, ValueError):
245	n/a	continue
246	n/a	return pairings
247	n/a	def restore_locale(self, saved):
248	n/a	for lc, setting in saved:
249	n/a	locale.setlocale(lc, setting)
250	n/a
251	n/a	def get_warnings_showwarning(self):
252	n/a	return warnings.showwarning
253	n/a	def restore_warnings_showwarning(self, fxn):
254	n/a	warnings.showwarning = fxn
255	n/a
256	n/a	def resource_info(self):
257	n/a	for name in self.resources:
258	n/a	method_suffix = name.replace('.', '_')
259	n/a	get_name = 'get_' + method_suffix
260	n/a	restore_name = 'restore_' + method_suffix
261	n/a	yield name, getattr(self, get_name), getattr(self, restore_name)
262	n/a
263	n/a	def __enter__(self):
264	n/a	self.saved_values = dict((name, get()) for name, get, restore
265	n/a	in self.resource_info())
266	n/a	return self
267	n/a
268	n/a	def __exit__(self, exc_type, exc_val, exc_tb):
269	n/a	saved_values = self.saved_values
270	n/a	del self.saved_values
271	n/a	support.gc_collect() # Some resources use weak references
272	n/a	for name, get, restore in self.resource_info():
273	n/a	current = get()
274	n/a	original = saved_values.pop(name)
275	n/a	# Check for changes to the resource's value
276	n/a	if current != original:
277	n/a	self.changed = True
278	n/a	restore(original)
279	n/a	if not self.quiet and not self.pgo:
280	n/a	print(f"Warning -- {name} was modified by {self.testname}",
281	n/a	file=sys.stderr, flush=True)
282	n/a	if self.verbose > 1:
283	n/a	print(f" Before: {original}\n After: {current} ",
284	n/a	file=sys.stderr, flush=True)
285	n/a	return False