Avoid OOM in refill fuzz test
Avoid OOM in refill fuzz test

If two things happen at the same time:

1. the input string has a huge prefix which is taken to be the
   indentation (such as “- - - - -”), and
2. the wrapping with is set to something small (such as 0),

then we can end up allocating an enormous amount of data in the
output. The problem is that we add the indentation on every line of
the output, and we end up with a huge number of lines when the line
width is small.

This was reported in OSS-Fuzz, please see
https://oss-fuzz.com/testcase-detail/4890847154143232.

mgeisler/textwrap