Re: 9.5Beta1 psql wrapped format expanded output

On Fri, Oct 23, 2015 at 5:11 PM, Jeff Janes <jeff(dot)janes(at)gmail(dot)com> wrote:

> On Fri, Oct 23, 2015 at 3:06 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> > Alvaro Herrera <alvherre(at)2ndquadrant(dot)com> writes:
> >> Jeff Janes wrote:
> >>> When I use psql with wrapped format with expanded output, I get the
> >>> period that is supposed to be at the end of the line being at the
> >>> beginning of the next line.
> >>>
> >>> Can anyone else verify this? I want to verify it is not some local
> >>> issue before looking into it too far.
> >
> >> Yes, I see it too.
> >
> > Me too. It looks like the code is overoptimistic about how much data
> > it can print on one line.
> >
> > 9.4 does not seem to try to wrap at all in this case.
>
> Yeah, support for wrapping in the extended format was added in 9.4 but
> reverted from that branch.
>
> This patch seems to fix the problem although I don't fully understand why.
>
> The reason swidth is 3 greater with border 1 than it is with border 0
> is that border 1 reserves a space at the right edge for the
> continuation period, while border 0 doesn't reserve a space and simply
> takes it out of the printable area if needed.
>
> Why swidth for border 2 is three greater than it is with border 1, I
> don't really know.
>

Now I see why. Border 2 doesn't just add a '|' on either end of the line,
but also adds a space to the left end, so that the "column" name is not
hard up against the preceding '|'

So I think my patch is correct.

Cheers,

Jeff