Issue #20245: The open functions in the tarfile module now correctly handle empty mode.
diff --git a/Lib/tarfile.py b/Lib/tarfile.py
index 16d338c..987c011 100755
--- a/Lib/tarfile.py
+++ b/Lib/tarfile.py
@@ -1429,10 +1429,11 @@
can be determined, `mode' is overridden by `fileobj's mode.
`fileobj' is not closed, when TarFile is closed.
"""
- if len(mode) > 1 or mode not in "raw":
+ modes = {"r": "rb", "a": "r+b", "w": "wb"}
+ if mode not in modes:
raise ValueError("mode must be 'r', 'a' or 'w'")
self.mode = mode
- self._mode = {"r": "rb", "a": "r+b", "w": "wb"}[mode]
+ self._mode = modes[mode]
if not fileobj:
if self.mode == "a" and not os.path.exists(name):
@@ -1588,7 +1589,7 @@
filemode = filemode or "r"
comptype = comptype or "tar"
- if filemode not in "rw":
+ if filemode not in ("r", "w"):
raise ValueError("mode must be 'r' or 'w'")
stream = _Stream(name, filemode, comptype, fileobj, bufsize)
@@ -1600,7 +1601,7 @@
t._extfileobj = False
return t
- elif mode in "aw":
+ elif mode in ("a", "w"):
return cls.taropen(name, mode, fileobj, **kwargs)
raise ValueError("undiscernible mode")
@@ -1609,7 +1610,7 @@
def taropen(cls, name, mode="r", fileobj=None, **kwargs):
"""Open uncompressed tar archive name for reading or writing.
"""
- if len(mode) > 1 or mode not in "raw":
+ if mode not in ("r", "a", "w"):
raise ValueError("mode must be 'r', 'a' or 'w'")
return cls(name, mode, fileobj, **kwargs)
@@ -1618,7 +1619,7 @@
"""Open gzip compressed tar archive name for reading or writing.
Appending is not allowed.
"""
- if len(mode) > 1 or mode not in "rw":
+ if mode not in ("r", "w"):
raise ValueError("mode must be 'r' or 'w'")
try:
@@ -1649,7 +1650,7 @@
"""Open bzip2 compressed tar archive name for reading or writing.
Appending is not allowed.
"""
- if len(mode) > 1 or mode not in "rw":
+ if mode not in ("r", "w"):
raise ValueError("mode must be 'r' or 'w'.")
try: