Re: Tighten up a few overly lax regexes in pg_dump's tap tests

On Monday, February 4, 2019, David Rowley <david(dot)rowley(at)2ndquadrant(dot)com>
wrote:

> On Tue, 5 Feb 2019 at 01:12, Daniel Gustafsson <daniel(at)yesql(dot)se> wrote:
> > We may also want to use the + metacharacter instead of * in a few
> places, since
> > the intent is to always match something, where matching nothing should be
> > considered an error:
> >
> > - qr/^ALTER TEXT SEARCH DICTIONARY
> dump_test.alt_ts_dict1 OWNER TO .*;/m,
> > + qr/^ALTER TEXT SEARCH DICTIONARY
> dump_test\.alt_ts_dict1 OWNER TO .*;/m,
>
> I looked for instances of * alone and didn't see any. I only saw ones
> prefixed with ".", in which case, isn't that matching 1 or more chars
> already?

No. In Regex the following are equivalent:

.* == .{0,}
.+ == .{1,}
. == .{1}

A “*” by itself would either be an error or, assuming the preceding
character is a space (so it visually looks alone) would be zero or more
consecutive spaces.

In the above “...OWNER TO<space>;” is a valid match.

David J.