pg_basebackup check vs Windows file path limits

The buildfarm animal fairywren has been failing the tests for
pg_basebackup because it can't create a file with a path longer than 255
chars. This has just been tripped because for release 16 it's running
TAP tests, and the branch name is part of the file path, and
"REL_16_STABLE" is longer than "HEAD". I did think of chdir'ing into the
directory to create the file, but experimentation shows that doesn't
solve matters. I also adjusted the machine's settings related to long
file names, but to no avail, so for now I propose to reduce slightly the
name of the long file so it still exercises the check for file names
longer than 100 but doesn't trip this up on fairywren. But that's a
bandaid. I don't have a good solution for now.

cheers

andrew

--
Andrew Dunstan
EDB:https://www.enterprisedb.com