diff --git a/Lib/_pyio.py b/Lib/_pyio.py index 43c24342ad6162..0b6493bc8dc926 100644 --- a/Lib/_pyio.py +++ b/Lib/_pyio.py @@ -405,6 +405,16 @@ def close(self): def __del__(self): """Destructor. Calls close().""" + try: + closed = self.closed + except Exception: + # If getting closed fails, then the object is probably + # in an unusable state, so ignore. + return + + if closed: + return + if _IOBASE_EMITS_UNRAISABLE: self.close() else: diff --git a/Lib/test/test_io.py b/Lib/test/test_io.py index 3a1f5ba5b6663d..55686d74398355 100644 --- a/Lib/test/test_io.py +++ b/Lib/test/test_io.py @@ -277,6 +277,10 @@ def readable(self): def seekable(self): return True + def seek(self, pos, whence=0): + # naive implementation, enough for tests + return 0 + def writable(self): return True @@ -1486,6 +1490,9 @@ def test_misbehaved_io(self): self.assertRaises(OSError, bufio.seek, 0) self.assertRaises(OSError, bufio.tell) + # Silence destructor error + bufio.close = lambda: None + def test_no_extraneous_read(self): # Issue #9550; when the raw IO object has satisfied the read request, # we should not issue any additional reads, otherwise it may block @@ -1834,6 +1841,9 @@ def test_misbehaved_io(self): self.assertRaises(OSError, bufio.tell) self.assertRaises(OSError, bufio.write, b"abcdef") + # Silence destructor error + bufio.close = lambda: None + def test_max_buffer_size_removal(self): with self.assertRaises(TypeError): self.tp(self.MockRawIO(), 8, 12) @@ -2060,6 +2070,11 @@ def writer_close(): # Silence destructor error writer.close = lambda: None + writer = None + + with support.catch_unraisable_exception(): + pair = None + support.gc_collect() def test_reader_writer_close_error_on_close(self): def reader_close(): diff --git a/Misc/NEWS.d/next/Library/2019-06-11-01-54-19.bpo-18748.ADqCkq.rst b/Misc/NEWS.d/next/Library/2019-06-11-01-54-19.bpo-18748.ADqCkq.rst new file mode 100644 index 00000000000000..295ddebb2a4015 --- /dev/null +++ b/Misc/NEWS.d/next/Library/2019-06-11-01-54-19.bpo-18748.ADqCkq.rst @@ -0,0 +1,2 @@ +:class:`_pyio.IOBase` destructor now does nothing if getting the ``closed`` +attribute fails to better mimick :class:`_io.IOBase` finalizer.