Issue #19222: Add support for the 'x' mode to the gzip module.
Original patch by Tim Heaney.
diff --git a/Lib/gzip.py b/Lib/gzip.py
index b073a66..8d21fe4 100644
--- a/Lib/gzip.py
+++ b/Lib/gzip.py
@@ -23,9 +23,9 @@
The filename argument can be an actual filename (a str or bytes object), or
an existing file object to read from or write to.
- The mode argument can be "r", "rb", "w", "wb", "a" or "ab" for binary mode,
- or "rt", "wt" or "at" for text mode. The default mode is "rb", and the
- default compresslevel is 9.
+ The mode argument can be "r", "rb", "w", "wb", "x", "xb", "a" or "ab" for
+ binary mode, or "rt", "wt", "xt" or "at" for text mode. The default mode is
+ "rb", and the default compresslevel is 9.
For binary mode, this function is equivalent to the GzipFile constructor:
GzipFile(filename, mode, compresslevel). In this case, the encoding, errors
@@ -151,11 +151,11 @@
fileobj, if discernible; otherwise, it defaults to the empty string,
and in this case the original filename is not included in the header.
- The mode argument can be any of 'r', 'rb', 'a', 'ab', 'w', or 'wb',
- depending on whether the file will be read or written. The default
+ The mode argument can be any of 'r', 'rb', 'a', 'ab', 'w', 'wb', 'x', or
+ 'xb' depending on whether the file will be read or written. The default
is the mode of fileobj if discernible; otherwise, the default is 'rb'.
A mode of 'r' is equivalent to one of 'rb', and similarly for 'w' and
- 'wb', and 'a' and 'ab'.
+ 'wb', 'a' and 'ab', and 'x' and 'xb'.
The compresslevel argument is an integer from 0 to 9 controlling the
level of compression; 1 is fastest and produces the least compression,
@@ -201,7 +201,7 @@
self.min_readsize = 100
fileobj = _PaddedFile(fileobj)
- elif mode.startswith(('w', 'a')):
+ elif mode.startswith(('w', 'a', 'x')):
self.mode = WRITE
self._init_write(filename)
self.compress = zlib.compressobj(compresslevel,
diff --git a/Lib/test/test_gzip.py b/Lib/test/test_gzip.py
index 37fe853..aeafc65 100644
--- a/Lib/test/test_gzip.py
+++ b/Lib/test/test_gzip.py
@@ -131,6 +131,14 @@
if not ztxt: break
self.assertEqual(contents, b'a'*201)
+ def test_exclusive_write(self):
+ with gzip.GzipFile(self.filename, 'xb') as f:
+ f.write(data1 * 50)
+ with gzip.GzipFile(self.filename, 'rb') as f:
+ self.assertEqual(f.read(), data1 * 50)
+ with self.assertRaises(FileExistsError):
+ gzip.GzipFile(self.filename, 'xb')
+
def test_buffered_reader(self):
# Issue #7471: a GzipFile can be wrapped in a BufferedReader for
# performance.
@@ -206,6 +214,9 @@
self.test_write()
with gzip.GzipFile(self.filename, 'r') as f:
self.assertEqual(f.myfileobj.mode, 'rb')
+ support.unlink(self.filename)
+ with gzip.GzipFile(self.filename, 'x') as f:
+ self.assertEqual(f.myfileobj.mode, 'xb')
def test_1647484(self):
for mode in ('wb', 'rb'):
@@ -414,35 +425,59 @@
class TestOpen(BaseTest):
def test_binary_modes(self):
uncompressed = data1 * 50
+
with gzip.open(self.filename, "wb") as f:
f.write(uncompressed)
with open(self.filename, "rb") as f:
file_data = gzip.decompress(f.read())
self.assertEqual(file_data, uncompressed)
+
with gzip.open(self.filename, "rb") as f:
self.assertEqual(f.read(), uncompressed)
+
with gzip.open(self.filename, "ab") as f:
f.write(uncompressed)
with open(self.filename, "rb") as f:
file_data = gzip.decompress(f.read())
self.assertEqual(file_data, uncompressed * 2)
+ with self.assertRaises(FileExistsError):
+ gzip.open(self.filename, "xb")
+ support.unlink(self.filename)
+ with gzip.open(self.filename, "xb") as f:
+ f.write(uncompressed)
+ with open(self.filename, "rb") as f:
+ file_data = gzip.decompress(f.read())
+ self.assertEqual(file_data, uncompressed)
+
def test_implicit_binary_modes(self):
# Test implicit binary modes (no "b" or "t" in mode string).
uncompressed = data1 * 50
+
with gzip.open(self.filename, "w") as f:
f.write(uncompressed)
with open(self.filename, "rb") as f:
file_data = gzip.decompress(f.read())
self.assertEqual(file_data, uncompressed)
+
with gzip.open(self.filename, "r") as f:
self.assertEqual(f.read(), uncompressed)
+
with gzip.open(self.filename, "a") as f:
f.write(uncompressed)
with open(self.filename, "rb") as f:
file_data = gzip.decompress(f.read())
self.assertEqual(file_data, uncompressed * 2)
+ with self.assertRaises(FileExistsError):
+ gzip.open(self.filename, "x")
+ support.unlink(self.filename)
+ with gzip.open(self.filename, "x") as f:
+ f.write(uncompressed)
+ with open(self.filename, "rb") as f:
+ file_data = gzip.decompress(f.read())
+ self.assertEqual(file_data, uncompressed)
+
def test_text_modes(self):
uncompressed = data1.decode("ascii") * 50
uncompressed_raw = uncompressed.replace("\n", os.linesep)
@@ -477,6 +512,8 @@
with self.assertRaises(ValueError):
gzip.open(self.filename, "wbt")
with self.assertRaises(ValueError):
+ gzip.open(self.filename, "xbt")
+ with self.assertRaises(ValueError):
gzip.open(self.filename, "rb", encoding="utf-8")
with self.assertRaises(ValueError):
gzip.open(self.filename, "rb", errors="ignore")