tests/helper.py

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