The problem was that an exception can occur in the text.get() call or
in the write() call, when the text buffer contains non-ASCII
characters. This causes the previous contents of the file to be lost.
The provisional fix is to call str(self.text.get(...)) *before*
opening the file, so that if the exception occurs, we never open the
file.
Two orthogonal better solutions have to wait for policy decisions:
1. We could try to encode the data as Latin-1 or as UTF-8; but that
would require IDLE to grow a notion of file encoding which requires
more thought.
2. We could make backups before overwriting a file. This requires
more thought because it needs to be fast and cross-platform and
configurable.
Much has changed -- too much, in fact, to write down.
The big news is that there's a standard way to write IDLE extensions;
see extend.txt. Some sample extensions have been provided, and
some existing code has been converted to extensions. Probably the
biggest new user feature is a new search dialog with more options,
search and replace, and even search in files (grep).
This is exactly as downloaded from my laptop after returning
from the holidays -- it hasn't even been tested on Unix yet.
