Re: VC command for showing outgoing changes

[Dan Nicolaescu <dann@ics.uci.edu>]

Stefan Monnier <monnier@iro.umontreal.ca> writes:

  > >> Here's a patch that implements the generic vc-incoming, vc-outgoing and
  > >> implements the backend specific functions for bzr, hg and partially for
  > >> git (no incoming and outgoing is not quite right).
  > 
  > I'd call them vc-log-incoming and vc-log-outgoing, to make it clear that
  > it shows this info in the form of a changelog (we could also have
  > vc-diff-incoming, vc-diff-outgoing, for example).

OK.

  > [ Another option might be to specify the `outgoing' or `incoming' as
  >   arguments to vc-print-log or vc-diff.  Basically your `vc-(in|out)going'
  >   is like (vc-print-log from-upstream to working-revision).  ]

That's 

  > > +(defun vc-outgoing-internal (backend remote-location)
  > > +  (let ((buff-name "*vc-outgoing*"))
  > > +    (vc-call-backend backend 'outgoing buff-name remote-location)
  > > +    (pop-to-buffer buff-name)
  > > +    (vc-exec-after
  > > +     `(let ((inhibit-read-only t)
  > > +	    (vc-log-view-type 'outgoing))
  > > +	(vc-call-backend ',backend 'log-view-mode)
  > > +	(set (make-local-variable 'log-view-vc-backend) ',backend)
  > > +	(set (make-local-variable 'log-view-vc-fileset) nil)
  > > +	(shrink-window-if-larger-than-buffer)
  > > +	(setq vc-sentinel-movepoint (point))
  > > +	(set-buffer-modified-p nil)))))
  > 
  > The redundancy between these two functions is bad.  Worse: there's

It's mostly an effect of how this was done: I just did outgoing, and
before sending this email copied + replaced outgoing->incoming as it was
the quickest way to get it done.

  > redundancy between this duplicate code and vc-print-log-internal as
  > well, some of what is different is a bug:
  > (vc-call-backend ',backend 'log-view-mode) should be called before
  > `vc-exec-after', as seen in vc-print-log-internal.

That change came after I wrote vc-outgoing-internal...

  > Also incoming/outgoing will probably want to obey vc-log-short-style, so
  > we really want to use as much of vc-print-log-internal as possible here.

It won't work: outgoing/incoming are project wide, so the directory vs
file logic used for vc-log-short-style does not apply.

  > > -(defvar vc-short-log)
  > > +(defvar log-view-type)
  >  
  > >  (define-derived-mode vc-hg-log-view-mode log-view-mode "Hg-Log-View"
  > >    (require 'add-log) ;; we need the add-log faces
  > >    (set (make-local-variable 'log-view-file-re) "\\`a\\`")
  > >    (set (make-local-variable 'log-view-per-file-logs) nil)
  > >    (set (make-local-variable 'log-view-message-re)
  > > -       (if vc-short-log
  > > +       (if (eq log-view-type 'short)
  > >             "^\\([0-9]+\\)\\(?:\\[.*\\]\\)? +\\([0-9a-z]\\{12\\}\\) +\\(\\(?:[0-9]+\\)-\\(?:[0-9]+\\)-\\(?:[0-9]+\\) \\(?:[0-9]+\\):\\(?:[0-9]+\\) \\(?:[-+0-9]+\\)\\) +\\(.*\\)$"
  > j

  > Ah, so that's why you use dynamic-scoping for log-view-type, so it's
  > available while setting up the major-mode.
  > 
  > Hmm...

Exactly it's ugly, but... 

  > And there's another related problem:
  > 
  > > +       (if (memq log-view-type '(short outgoing))
  > 
  > This is becoming very ad-hoc.  I think the right answer is to let the
  > print-log backend operation set something up that the log-view-mode
  > operation can use subsequently.  I.e. remove `log-view-mode' from the
  > generic part of the code, and let the backend set some permanent-local
  > variable in `print-log' to tell the subsequent `log-view-mode' which
  > kind of log to expect.
  > 
  > We could still define a generic `log-view-type' or `log-view-format'
  > variable for it, tho.  The idea is that the generic part of the code may
  > want to use it, e.g. to display it in the mode-line (and let button-2
  > run a command that changes the format to something else).  But it should
  > be set by the backend's `print-log' operation rather than by the
  > generic code.
  > 
  > WDYT?
  > 
  > 
  >         Stefan