Python msvcrt.CRT_ASSERT Examples

def setup_tests(ns):
    if ns.testdir:
        # Prepend test directory to sys.path, so runtest() will be able
        # to locate tests
        sys.path.insert(0, os.path.abspath(ns.testdir))
    if ns.huntrleaks:
        # Avoid false positives due to various caches
        # filling slowly with random data:
        warm_caches()
    if ns.memlimit is not None:
        support.set_memlimit(ns.memlimit)
    if ns.threshold is not None:
        import gc
        gc.set_threshold(ns.threshold)
    if ns.nowindows:
        print('The --nowindows (-n) option is deprecated. '
              'Use -vv to display assertions in stderr.')
    try:
        import msvcrt
    except ImportError:
        pass
    else:
        msvcrt.SetErrorMode(msvcrt.SEM_FAILCRITICALERRORS|
                            msvcrt.SEM_NOALIGNMENTFAULTEXCEPT|
                            msvcrt.SEM_NOGPFAULTERRORBOX|
                            msvcrt.SEM_NOOPENFILEERRORBOX)
        try:
            msvcrt.CrtSetReportMode
        except AttributeError:
            # release build
            pass
        else:
            for m in [msvcrt.CRT_WARN, msvcrt.CRT_ERROR, msvcrt.CRT_ASSERT]:
                if ns.verbose and ns.verbose >= 2:
                    msvcrt.CrtSetReportMode(m, msvcrt.CRTDBG_MODE_FILE)
                    msvcrt.CrtSetReportFile(m, msvcrt.CRTDBG_FILE_STDERR)
                else:
                    msvcrt.CrtSetReportMode(m, 0) 

def fd_count():
    """Count the number of open file descriptors.
    """
    if sys.platform.startswith(('linux', 'freebsd')):
        try:
            names = os.listdir("/proc/self/fd")
            # Substract one because listdir() opens internally a file
            # descriptor to list the content of the /proc/self/fd/ directory.
            return len(names) - 1
        except OSError as exc:
            if exc.errno != errno.ENOENT:
                raise

    MAXFD = 256
    if hasattr(os, 'sysconf'):
        try:
            MAXFD = os.sysconf("SC_OPEN_MAX")
        except OSError:
            pass

    old_modes = None
    if sys.platform == 'win32':
        # bpo-25306, bpo-31009: Call CrtSetReportMode() to not kill the process
        # on invalid file descriptor if Python is compiled in debug mode
        try:
            import msvcrt
            msvcrt.CrtSetReportMode
        except (AttributeError, ImportError):
            # no msvcrt or a release build
            pass
        else:
            old_modes = {}
            for report_type in (msvcrt.CRT_WARN,
                                msvcrt.CRT_ERROR,
                                msvcrt.CRT_ASSERT):
                old_modes[report_type] = msvcrt.CrtSetReportMode(report_type, 0)

    try:
        count = 0
        for fd in range(MAXFD):
            try:
                # Prefer dup() over fstat(). fstat() can require input/output
                # whereas dup() doesn't.
                fd2 = os.dup(fd)
            except OSError as e:
                if e.errno != errno.EBADF:
                    raise
            else:
                os.close(fd2)
                count += 1
    finally:
        if old_modes is not None:
            for report_type in (msvcrt.CRT_WARN,
                                msvcrt.CRT_ERROR,
                                msvcrt.CRT_ASSERT):
                msvcrt.CrtSetReportMode(report_type, old_modes[report_type])

    return count 

def __enter__(self):
        """On Windows, disable Windows Error Reporting dialogs using
        SetErrorMode.

        On UNIX, try to save the previous core file size limit, then set
        soft limit to 0.
        """
        if sys.platform.startswith('win'):
            # see http://msdn.microsoft.com/en-us/library/windows/desktop/ms680621.aspx
            # GetErrorMode is not available on Windows XP and Windows Server 2003,
            # but SetErrorMode returns the previous value, so we can use that
            import ctypes
            self._k32 = ctypes.windll.kernel32
            SEM_NOGPFAULTERRORBOX = 0x02
            self.old_value = self._k32.SetErrorMode(SEM_NOGPFAULTERRORBOX)
            self._k32.SetErrorMode(self.old_value | SEM_NOGPFAULTERRORBOX)

            # Suppress assert dialogs in debug builds
            # (see http://bugs.python.org/issue23314)
            try:
                import msvcrt
                msvcrt.CrtSetReportMode
            except (AttributeError, ImportError):
                # no msvcrt or a release build
                pass
            else:
                self.old_modes = {}
                for report_type in [msvcrt.CRT_WARN,
                                    msvcrt.CRT_ERROR,
                                    msvcrt.CRT_ASSERT]:
                    old_mode = msvcrt.CrtSetReportMode(report_type,
                            msvcrt.CRTDBG_MODE_FILE)
                    old_file = msvcrt.CrtSetReportFile(report_type,
                            msvcrt.CRTDBG_FILE_STDERR)
                    self.old_modes[report_type] = old_mode, old_file

        else:
            if resource is not None:
                try:
                    self.old_value = resource.getrlimit(resource.RLIMIT_CORE)
                    resource.setrlimit(resource.RLIMIT_CORE,
                                       (0, self.old_value[1]))
                except (ValueError, OSError):
                    pass
            if sys.platform == 'darwin':
                # Check if the 'Crash Reporter' on OSX was configured
                # in 'Developer' mode and warn that it will get triggered
                # when it is.
                #
                # This assumes that this context manager is used in tests
                # that might trigger the next manager.
                value = subprocess.Popen(['/usr/bin/defaults', 'read',
                        'com.apple.CrashReporter', 'DialogType'],
                        stdout=subprocess.PIPE).communicate()[0]
                if value.strip() == b'developer':
                    print("this test triggers the Crash Reporter, "
                          "that is intentional", end='', flush=True)

        return self