Re: [PATCH 2/2] t3430: update to test with custom commentChar

From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Jul 10, 2018, 13:08 UTC
Message-ID: <nycvar.QRO.7.76.6.1807101504530.75@tvgsbejvaqbjf.bet>
In-Reply-To: <aa716d3f-6a80-e3fc-0172-1027fb85c792@living180.net>

Hi Daniel,

On Tue, 10 Jul 2018, Daniel Harding wrote:

Show 47 quoted lines

> On Mon, 09 Jul 2018 at 22:14:58 +0300, Johannes Schindelin wrote:
> > 
> > On Mon, 9 Jul 2018, Daniel Harding wrote:
> > > 
> > > On Mon, 09 Jul 2018 at 00:02:00 +0300, brian m. carlson wrote:
> > > >
> > > > Should this affect the "# Merge the topic branch" line (and the "# C",
> > > > "# E", and "# H" lines in the next test) that appears below this?  It
> > > > would seem those would qualify as comments as well.
> > >
> > > I intentionally did not change that behavior for two reasons:
> > >
> > > a) from a Git perspective, comment characters are only effectual for
> > > comments
> > > if they are the first character in a line
> > >
> > > and
> > >
> > > b) there are places where a '#' character from the todo list is actually
> > > parsed and used e.g. [0] and [1].  I have not yet gotten to the point of
> > > grokking what is going on there, so I didn't want to risk breaking
> > > something I
> > > didn't understand.  Perhaps Johannes could shed some light on whether the
> > > cases you mentioned should be changed to use the configured commentChar or
> > > not.
> > >
> > > [0]
> > > https://github.com/git/git/blob/53f9a3e157dbbc901a02ac2c73346d375e24978c/sequencer.c#L2869
> > > [1]
> > > https://github.com/git/git/blob/53f9a3e157dbbc901a02ac2c73346d375e24978c/sequencer.c#L3797
> > 
> > These are related. The first one tries to support
> > 
> >  merge -C cafecafe second-branch third-branch # Octopus 2nd/3rd branch
> > 
> > i.e. use '#' to separate between the commit(s) to merge and the oneline
> > (the latter for the reader's pleasure, just like the onelines in the `pick
> > <hash> <oneline>` lines.
> > 
> > The second ensures that there is no valid label `#`.
> > 
> > I have not really thought about the ramifications of changing this to
> > comment_line_char, but I guess it *could* work if both locations were
> > changed.
> 
> Is there interest in such a change?  I'm happy to take a stab at it if there
> is, otherwise I'll leave things as they are.

I think it would be a fine change, once we convinced ourselves that it does not break things (I am a little worried about this because I remember just how long I had to reflect about the ramifications with regards to the label: `#` is a valid ref name, after all, and that was the reason why I had to treat it specially, and I wonder whether allowing arbitrary comment chars will require us to add more such special handling that is not necessary if we stick to `#`).

Not that the comment line char feature seems to be all that safe. I could imagine that setting it to ' ' (i.e. a single space) wreaks havoc with Git, and we have no safeguard to error out in this obviously broken case.

Ciao, Dscho