Re: [PATCH] pretty format string support for reflog times

[Jeff King <peff@peff.net>]

On Wed, Jul 27, 2016 at 04:14:14AM -0400, Phil Pennock wrote:

> The reflog contains timestamp information, but these were not exposed to
> `--pretty`.  Four of the six author/committer format string
> second-letters were still available and copied, but `d`/`D` are taken
> for reflog selector formatting.  So use `%gT` for "time" instead of
> "date" mnemonic for using `--date=...` formatting.

Hrm. Since Ted was not cc'd, it is not clear to me whether this is
coincidental or in response to the thread over in

  http://thread.gmane.org/gmane.comp.version-control.git/299201

To summarize, I think the conclusion there was that we would go with at
least the 't' and 'r' formatters in the short term. The 'i/I' ones were
not something Ted cared about that much, I think, but they do make
things orthogonal with the other ident dates.

Your '%gT' seems like a nice idea in principle, though I'm not sure it
is all that useful due to the way that --date impacts %gd.  In other
words:

  git log -g --format=%gd --date=rfc

will already respect --date (albeit with "ref@{...}" wrapped around it).
But even with your patch, you cannot do:

  git log -g --format="%gd %gT" --date=rfc

to get "HEAD@{0} ...rfc-date...", because the presence of "--date" is
the trigger to switch the meaning of "%gd".

So the final solution is more like:

  - a formatter for just the reflog time, respecting date

  - a formatter for just the reflog index (the "0" in HEAD@{0})

  - a formatter for the ref name (just the "HEAD" in HEAD@{0})

And I'm not sure if we want to do that now with a bunch of arcane
two-letter placeholders, or wait for a refactoring where they can get
more readable names like %(reflog-index).

-Peff