Issue #25913: Leading <~ is optional now in base64.a85decode() with adobe=True.
Patch by Swati Jaiswal.
diff --git a/Lib/base64.py b/Lib/base64.py
index e2c597b..adaec1d 100755
--- a/Lib/base64.py
+++ b/Lib/base64.py
@@ -367,10 +367,15 @@
"""
b = _bytes_from_decode_data(b)
if adobe:
- if not (b.startswith(_A85START) and b.endswith(_A85END)):
- raise ValueError("Ascii85 encoded byte sequences must be bracketed "
- "by {!r} and {!r}".format(_A85START, _A85END))
- b = b[2:-2] # Strip off start/end markers
+ if not b.endswith(_A85END):
+ raise ValueError(
+ "Ascii85 encoded byte sequences must end "
+ "with {!r}".format(_A85END)
+ )
+ if b.startswith(_A85START):
+ b = b[2:-2] # Strip off start/end markers
+ else:
+ b = b[:-2]
#
# We have to go through this stepwise, so as to ignore spaces and handle
# special short sequences
diff --git a/Lib/test/test_base64.py b/Lib/test/test_base64.py
index 9b853a8..4f86aaa 100644
--- a/Lib/test/test_base64.py
+++ b/Lib/test/test_base64.py
@@ -494,6 +494,7 @@
eq(base64.a85decode(data, adobe=False), res, data)
eq(base64.a85decode(data.decode("ascii"), adobe=False), res, data)
eq(base64.a85decode(b'<~' + data + b'~>', adobe=True), res, data)
+ eq(base64.a85decode(data + b'~>', adobe=True), res, data)
eq(base64.a85decode('<~%s~>' % data.decode("ascii"), adobe=True),
res, data)
@@ -584,8 +585,6 @@
b"malformed", adobe=True)
self.assertRaises(ValueError, base64.a85decode,
b"<~still malformed", adobe=True)
- self.assertRaises(ValueError, base64.a85decode,
- b"also malformed~>", adobe=True)
# With adobe=False (the default), Adobe framing markers are disallowed
self.assertRaises(ValueError, base64.a85decode,
diff --git a/Misc/NEWS b/Misc/NEWS
index c47ca60..fd4ca59 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -76,6 +76,9 @@
Library
-------
+- Issue #25913: Leading ``<~`` is optional now in base64.a85decode() with
+ adobe=True. Patch by Swati Jaiswal.
+
- Issue #26186: Remove an invalid type check in importlib.util.LazyLoader.
- Issue #26367: importlib.__import__() raises SystemError like