Issue #21560: An attempt to write a data of wrong type no longer cause
GzipFile corruption. Original patch by Wolfgang Maier.
diff --git a/Lib/gzip.py b/Lib/gzip.py
index 49566fd..83cc077 100644
--- a/Lib/gzip.py
+++ b/Lib/gzip.py
@@ -238,9 +238,9 @@
data = data.tobytes()
if len(data) > 0:
- self.size = self.size + len(data)
+ self.fileobj.write(self.compress.compress(data))
+ self.size += len(data)
self.crc = zlib.crc32(data, self.crc) & 0xffffffffL
- self.fileobj.write( self.compress.compress(data) )
self.offset += len(data)
return len(data)
diff --git a/Lib/test/test_gzip.py b/Lib/test/test_gzip.py
index 7f24981..41857c7 100644
--- a/Lib/test/test_gzip.py
+++ b/Lib/test/test_gzip.py
@@ -30,6 +30,14 @@
def tearDown(self):
test_support.unlink(self.filename)
+ def write_and_read_back(self, data, mode='b'):
+ b_data = memoryview(data).tobytes()
+ with gzip.GzipFile(self.filename, 'w'+mode) as f:
+ l = f.write(data)
+ self.assertEqual(l, len(b_data))
+ with gzip.GzipFile(self.filename, 'r'+mode) as f:
+ self.assertEqual(f.read(), b_data)
+
@test_support.requires_unicode
def test_unicode_filename(self):
unicode_filename = test_support.TESTFN_UNICODE
@@ -60,6 +68,25 @@
# Test multiple close() calls.
f.close()
+ # The following test_write_xy methods test that write accepts
+ # the corresponding bytes-like object type as input
+ # and that the data written equals bytes(xy) in all cases.
+ def test_write_memoryview(self):
+ self.write_and_read_back(memoryview(data1 * 50))
+
+ def test_write_incompatible_type(self):
+ # Test that non-bytes-like types raise TypeError.
+ # Issue #21560: attempts to write incompatible types
+ # should not affect the state of the fileobject
+ with gzip.GzipFile(self.filename, 'wb') as f:
+ with self.assertRaises(UnicodeEncodeError):
+ f.write(u'\xff')
+ with self.assertRaises(TypeError):
+ f.write([1])
+ f.write(data1)
+ with gzip.GzipFile(self.filename, 'rb') as f:
+ self.assertEqual(f.read(), data1)
+
def test_read(self):
self.test_write()
# Try reading.