tests/helper.py

   1 import contextlib
   2 import unittest
   3 import inspect
   4 import warnings
   5 import functools
   6 import sys
   7 from collections import namedtuple
   8
   9 import gi
  10 from gi import PyGIDeprecationWarning
  11 from gi.repository import GLib
  12
  13 from compathelper import callable, StringIO
  14
  15
  16 ExceptionInfo = namedtuple("ExceptionInfo", ["type", "value", "traceback"])
  17 """The type used for storing exceptions used by capture_exceptions()"""
  18
  19
  20 @contextlib.contextmanager
  21 def capture_exceptions():
  22     """Installs a temporary sys.excepthook which records all exceptions
  23     instead of printing them.
  24     """
  25
  26     exceptions = []
  27
  28     def custom_excepthook(*args):
  29         exceptions.append(ExceptionInfo(*args))
  30
  31     old_hook = sys.excepthook
  32     sys.excepthook = custom_excepthook
  33     try:
  34         yield exceptions
  35     finally:
  36         sys.excepthook = old_hook
  37
  38
  39 def ignore_gi_deprecation_warnings(func_or_class):
  40     """A unittest class and function decorator which makes them ignore
  41     PyGIDeprecationWarning.
  42     """
  43
  44     if inspect.isclass(func_or_class):
  45         assert issubclass(func_or_class, unittest.TestCase)
  46         cls = func_or_class
  47         for name, value in cls.__dict__.items():
  48             if callable(value) and name.startswith("test_"):
  49                 new_value = ignore_gi_deprecation_warnings(value)
  50                 setattr(cls, name, new_value)
  51         return cls
  52     else:
  53         func = func_or_class
  54
  55         @functools.wraps(func)
  56         def wrapper(*args, **kwargs):
  57             with capture_gi_deprecation_warnings():
  58                 return func(*args, **kwargs)
  59
  60         return wrapper
  61
  62
  63 @contextlib.contextmanager
  64 def capture_gi_deprecation_warnings():
  65     """Temporarily suppress PyGIDeprecationWarning output and record them"""
  66
  67     with warnings.catch_warnings(record=True) as warn:
  68         warnings.simplefilter('always', category=PyGIDeprecationWarning)
  69         yield warn
  70
  71
  72 @contextlib.contextmanager
  73 def capture_glib_warnings(allow_warnings=False, allow_criticals=False):
  74     """Temporarily suppress glib warning output and record them.
  75
  76     The test suite is run with G_DEBUG="fatal-warnings fatal-criticals"
  77     by default. Setting allow_warnings and allow_criticals will temporarily
  78     allow warnings or criticals without terminating the test run.
  79     """
  80
  81     old_mask = GLib.log_set_always_fatal(GLib.LogLevelFlags(0))
  82
  83     new_mask = old_mask
  84     if allow_warnings:
  85         new_mask &= ~GLib.LogLevelFlags.LEVEL_WARNING
  86     if allow_criticals:
  87         new_mask &= ~GLib.LogLevelFlags.LEVEL_CRITICAL
  88
  89     GLib.log_set_always_fatal(GLib.LogLevelFlags(new_mask))
  90
  91     GLibWarning = gi._gi._gobject.Warning
  92     try:
  93         with warnings.catch_warnings(record=True) as warn:
  94             warnings.filterwarnings('always', category=GLibWarning)
  95             yield warn
  96     finally:
  97         GLib.log_set_always_fatal(old_mask)
  98
  99
 100 @contextlib.contextmanager
 101 def capture_glib_deprecation_warnings():
 102     """Temporarily suppress glib deprecation warning output and record them"""
 103
 104     GLibWarning = gi._gi._gobject.Warning
 105     with warnings.catch_warnings(record=True) as warn:
 106         warnings.filterwarnings(
 107             'always', category=GLibWarning,
 108             message=".+ is deprecated and shouldn't be used anymore\. "
 109                     "It will be removed in a future version\.")
 110         yield warn
 111
 112
 113 @contextlib.contextmanager
 114 def capture_output():
 115     """
 116     with capture_output as (stdout, stderr):
 117         some_action()
 118     print(stdout.getvalue(), stderr.getvalue())
 119     """
 120
 121     err = StringIO()
 122     out = StringIO()
 123     old_err = sys.stderr
 124     old_out = sys.stdout
 125     sys.stderr = err
 126     sys.stdout = out
 127
 128     try:
 129         yield (out, err)
 130     finally:
 131         sys.stderr = old_err
 132         sys.stdout = old_out