$SUBJECT is not great. The options to pg_basebackup that are not tested by any part of the regression test suite include the single-letter options rlzZdUwWvP as well as --no-estimate-size.
It would probably be good to fix as much of this as we can, but there are a couple of cases I think would be particularly good to cover. One is 'pg_basebackup -Ft -Xnone -D -', which tries to write the output as a single tar file on standard output, injecting the backup_manifest file into the tar file instead of writing it out separately as we normally would. This case requires special handling in a few places and it would be good to check that it actually works. The other is the -z or -Z option, which produces a compressed tar file. Now, there's nothing to prevent us from running commands like this from the pg_basebackup tests, but it doesn't seem like we could really check anything meaningful. Perhaps we'd notice if the command exited non-zero or didn't produce any output, but it would be nice to verify that the resulting backups are actually correct. The way to do that would seem to be to extract the tar file (and decompress it first, in the -z/-Z case) and then run pg_verifybackup on the result and check that it passes. However, as far as I can tell there's no guarantee that the user has 'tar' or 'gunzip' installed on their system, so I don't see a clean way to do this. A short (but perhaps incomplete) search didn't turn up similar precedents in the existing tests. Any ideas? -- Robert Haas EDB: http://www.enterprisedb.com