diff options
Diffstat (limited to 'Lib')
| -rw-r--r-- | Lib/_pyio.py | 18 | ||||
| -rw-r--r-- | Lib/test/test_io.py | 116 |
2 files changed, 114 insertions, 20 deletions
diff --git a/Lib/_pyio.py b/Lib/_pyio.py index 37157d5..a467ddd 100644 --- a/Lib/_pyio.py +++ b/Lib/_pyio.py @@ -390,7 +390,7 @@ class IOBase(metaclass=abc.ABCMeta): def seekable(self): """Return a bool indicating whether object supports random access. - If False, seek(), tell() and truncate() will raise UnsupportedOperation. + If False, seek(), tell() and truncate() will raise OSError. This method may need to do a test seek(). """ return False @@ -405,7 +405,7 @@ class IOBase(metaclass=abc.ABCMeta): def readable(self): """Return a bool indicating whether object was opened for reading. - If False, read() will raise UnsupportedOperation. + If False, read() will raise OSError. """ return False @@ -419,7 +419,7 @@ class IOBase(metaclass=abc.ABCMeta): def writable(self): """Return a bool indicating whether object was opened for writing. - If False, write() and truncate() will raise UnsupportedOperation. + If False, write() and truncate() will raise OSError. """ return False @@ -787,12 +787,6 @@ class _BufferedIOMixin(BufferedIOBase): def seekable(self): return self.raw.seekable() - def readable(self): - return self.raw.readable() - - def writable(self): - return self.raw.writable() - @property def raw(self): return self._raw @@ -982,6 +976,9 @@ class BufferedReader(_BufferedIOMixin): self._reset_read_buf() self._read_lock = Lock() + def readable(self): + return self.raw.readable() + def _reset_read_buf(self): self._read_buf = b"" self._read_pos = 0 @@ -1170,6 +1167,9 @@ class BufferedWriter(_BufferedIOMixin): self._write_buf = bytearray() self._write_lock = Lock() + def writable(self): + return self.raw.writable() + def write(self, b): if self.closed: raise ValueError("write to closed file") diff --git a/Lib/test/test_io.py b/Lib/test/test_io.py index 86440c5..51c250b 100644 --- a/Lib/test/test_io.py +++ b/Lib/test/test_io.py @@ -203,6 +203,9 @@ class MockUnseekableIO: def tell(self, *args): raise self.UnsupportedOperation("not seekable") + def truncate(self, *args): + raise self.UnsupportedOperation("not seekable") + class CMockUnseekableIO(MockUnseekableIO, io.BytesIO): UnsupportedOperation = io.UnsupportedOperation @@ -361,6 +364,107 @@ class IOTest(unittest.TestCase): self.assertRaises(exc, fp.seek, 1, self.SEEK_CUR) self.assertRaises(exc, fp.seek, -1, self.SEEK_END) + def test_optional_abilities(self): + # Test for OSError when optional APIs are not supported + # The purpose of this test is to try fileno(), reading, writing and + # seeking operations with various objects that indicate they do not + # support these operations. + + def pipe_reader(): + [r, w] = os.pipe() + os.close(w) # So that read() is harmless + return self.FileIO(r, "r") + + def pipe_writer(): + [r, w] = os.pipe() + self.addCleanup(os.close, r) + # Guarantee that we can write into the pipe without blocking + thread = threading.Thread(target=os.read, args=(r, 100)) + thread.start() + self.addCleanup(thread.join) + return self.FileIO(w, "w") + + def buffered_reader(): + return self.BufferedReader(self.MockUnseekableIO()) + + def buffered_writer(): + return self.BufferedWriter(self.MockUnseekableIO()) + + def buffered_random(): + return self.BufferedRandom(self.BytesIO()) + + def buffered_rw_pair(): + return self.BufferedRWPair(self.MockUnseekableIO(), + self.MockUnseekableIO()) + + def text_reader(): + class UnseekableReader(self.MockUnseekableIO): + writable = self.BufferedIOBase.writable + write = self.BufferedIOBase.write + return self.TextIOWrapper(UnseekableReader(), "ascii") + + def text_writer(): + class UnseekableWriter(self.MockUnseekableIO): + readable = self.BufferedIOBase.readable + read = self.BufferedIOBase.read + return self.TextIOWrapper(UnseekableWriter(), "ascii") + + tests = ( + (pipe_reader, "fr"), (pipe_writer, "fw"), + (buffered_reader, "r"), (buffered_writer, "w"), + (buffered_random, "rws"), (buffered_rw_pair, "rw"), + (text_reader, "r"), (text_writer, "w"), + (self.BytesIO, "rws"), (self.StringIO, "rws"), + ) + for [test, abilities] in tests: + if test is pipe_writer and not threading: + continue # Skip subtest that uses a background thread + with self.subTest(test), test() as obj: + readable = "r" in abilities + self.assertEqual(obj.readable(), readable) + writable = "w" in abilities + self.assertEqual(obj.writable(), writable) + seekable = "s" in abilities + self.assertEqual(obj.seekable(), seekable) + + if isinstance(obj, self.TextIOBase): + data = "3" + elif isinstance(obj, (self.BufferedIOBase, self.RawIOBase)): + data = b"3" + else: + self.fail("Unknown base class") + + if "f" in abilities: + obj.fileno() + else: + self.assertRaises(OSError, obj.fileno) + + if readable: + obj.read(1) + obj.read() + else: + self.assertRaises(OSError, obj.read, 1) + self.assertRaises(OSError, obj.read) + + if writable: + obj.write(data) + else: + self.assertRaises(OSError, obj.write, data) + + if seekable: + obj.tell() + obj.seek(0) + else: + self.assertRaises(OSError, obj.tell) + self.assertRaises(OSError, obj.seek, 0) + + if writable and seekable: + obj.truncate() + obj.truncate(0) + else: + self.assertRaises(OSError, obj.truncate) + self.assertRaises(OSError, obj.truncate, 0) + def test_open_handles_NUL_chars(self): fn_with_NUL = 'foo\0bar' self.assertRaises(ValueError, self.open, fn_with_NUL, 'w') @@ -747,12 +851,6 @@ class CommonBufferedTests: self.assertEqual(42, bufio.fileno()) - @unittest.skip('test having existential crisis') - def test_no_fileno(self): - # XXX will we always have fileno() function? If so, kill - # this test. Else, write it. - pass - def test_invalid_args(self): rawio = self.MockRawIO() bufio = self.tp(rawio) @@ -780,13 +878,9 @@ class CommonBufferedTests: super().flush() rawio = self.MockRawIO() bufio = MyBufferedIO(rawio) - writable = bufio.writable() del bufio support.gc_collect() - if writable: - self.assertEqual(record, [1, 2, 3]) - else: - self.assertEqual(record, [1, 2]) + self.assertEqual(record, [1, 2, 3]) def test_context_manager(self): # Test usability as a context manager |