#9124: mailbox now accepts binary input and uses binary internally

Although this patch contains API changes and is rather weighty for an
RC phase, the mailbox module was essentially unusable without the patch
since it would produce UnicodeErrors when handling non-ascii input
at arbitrary and somewhat mysterious places, and any non-trivial amount
of email processing will encounter messages with non-ascii bytes.
The release manager approved the patch application.

The changes allow binary input, and reject non-ASCII string input early
with a useful message instead of failing mysteriously later.  Binary
is used internally for reading and writing the mailbox files.  StringIO
and Text file input are deprecated.

Initial patch by Victor Stinner, validated and expanded by R. David Murray.

1 files changed, 6 insertions, 0 deletions

diff --git a/Misc/NEWS b/Misc/NEWS
index 57b2440..3882a77 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -16,6 +16,12 @@ Core and Builtins
 Library
 -------
 
+- Issue #9124: mailbox now accepts binary input and reads and writes mailbox
+  files in binary mode, using the email package's binary support to parse
+  arbitrary email messages.  StringIO and text file input is deprecated,
+  and string input fails early if non-ASCII characters are used, where
+  previously it would fail when the email was processed in a later step.
+
 - Issue #10845: Mitigate the incompatibility between the multiprocessing
   module on Windows and the use of package, zipfile or directory execution
   by special casing main modules that actually *are* called __main__.py.