Issue #7865: The close() method of :mod:`io` objects should not swallow
exceptions raised by the implicit flush(). Also ensure that calling
close() several times is supported. Patch by Pascal Chambon.
diff --git a/Lib/_pyio.py b/Lib/_pyio.py
index 1343f1b..bdffb12 100644
--- a/Lib/_pyio.py
+++ b/Lib/_pyio.py
@@ -327,6 +327,7 @@
This is not implemented for read-only and non-blocking streams.
"""
+ self._checkClosed()
# XXX Should this return the number of bytes written???
__closed = False
@@ -337,10 +338,7 @@
This method has no effect if the file is already closed.
"""
if not self.__closed:
- try:
- self.flush()
- except IOError:
- pass # If flush() fails, just give up
+ self.flush()
self.__closed = True
def __del__(self):
@@ -709,14 +707,13 @@
### Flush and close ###
def flush(self):
+ if self.closed:
+ raise ValueError("flush of closed file")
self.raw.flush()
def close(self):
- if not self.closed and self.raw is not None:
- try:
- self.flush()
- except IOError:
- pass # If flush() fails, just give up
+ if self.raw is not None and not self.closed:
+ self.flush()
self.raw.close()
def detach(self):
@@ -1531,11 +1528,8 @@
self._telling = self._seekable
def close(self):
- if self.buffer is not None:
- try:
- self.flush()
- except IOError:
- pass # If flush() fails, just give up
+ if self.buffer is not None and not self.closed:
+ self.flush()
self.buffer.close()
@property
diff --git a/Lib/test/test_io.py b/Lib/test/test_io.py
index b3feb1b..2874d79 100644
--- a/Lib/test/test_io.py
+++ b/Lib/test/test_io.py
@@ -541,6 +541,20 @@
with self.open(zero, "r") as f:
self.assertRaises(OverflowError, f.read)
+ def test_flush_error_on_close(self):
+ f = self.open(support.TESTFN, "wb", buffering=0)
+ def bad_flush():
+ raise IOError()
+ f.flush = bad_flush
+ self.assertRaises(IOError, f.close) # exception not swallowed
+
+ def test_multi_close(self):
+ f = self.open(support.TESTFN, "wb", buffering=0)
+ f.close()
+ f.close()
+ f.close()
+ self.assertRaises(ValueError, f.flush)
+
class CIOTest(IOTest):
pass
@@ -642,6 +656,22 @@
raw.name = b"dummy"
self.assertEqual(repr(b), "<%s name='dummy'>" % clsname)
+ def test_flush_error_on_close(self):
+ raw = self.MockRawIO()
+ def bad_flush():
+ raise IOError()
+ raw.flush = bad_flush
+ b = self.tp(raw)
+ self.assertRaises(IOError, b.close) # exception not swallowed
+
+ def test_multi_close(self):
+ raw = self.MockRawIO()
+ b = self.tp(raw)
+ b.close()
+ b.close()
+ b.close()
+ self.assertRaises(ValueError, b.flush)
+
class BufferedReaderTest(unittest.TestCase, CommonBufferedTests):
read_mode = "rb"
@@ -2117,6 +2147,20 @@
for n in range(20):
self.assertEquals(content.count("Thread%03d\n" % n), 1)
+ def test_flush_error_on_close(self):
+ txt = self.TextIOWrapper(self.BytesIO(self.testdata), encoding="ascii")
+ def bad_flush():
+ raise IOError()
+ txt.flush = bad_flush
+ self.assertRaises(IOError, txt.close) # exception not swallowed
+
+ def test_multi_close(self):
+ txt = self.TextIOWrapper(self.BytesIO(self.testdata), encoding="ascii")
+ txt.close()
+ txt.close()
+ txt.close()
+ self.assertRaises(ValueError, txt.flush)
+
class CTextIOWrapperTest(TextIOWrapperTest):
def test_initialization(self):