Re: Make contrib modules' installation scripts more secure.

Re: To PostgreSQL Hackers
> I think this change neglected to add plpgsql to the extension
> dependencies in the .control file:
>
> 12:53:51 # Failed test 'psql -qc 'CREATE EXTENSION "cube"''
> 12:53:51 # at t/TestLib.pm line 213.
> 12:53:51 not ok 68 - psql -qc 'CREATE EXTENSION "cube"'
> 12:53:51 # got: '1'
> 12:53:51 # expected: '0'
> 12:53:51 not ok 69 - extension cube installs without error
> 12:53:51 # Failed test 'extension cube installs without error'
> 12:53:51 # at t/TestLib.pm line 214.
> 12:53:51 # got: 'ERROR: language "plpgsql" does not exist
> 12:53:51 # HINT: Use CREATE EXTENSION to load the language into the database.
> 12:53:51 # '

Or maybe the argument is that the extension needs plpgsql only at
install time, and not to run, and you could really remove it after the
CREATE EXTENSION has been done. But that argument feels pretty icky.
And dump-restore would fail.

At least the error message is very explicit.

Christoph