D803: extdiff: allow pager to be used

[quark (Jun Wu)]

quark added a comment.


  In https://phab.mercurial-scm.org/D803#14125, @yuja wrote:
  
  > It seems confusing to support the global pager.attend-* option only in extdiff context.
  >  Instead, maybe we can use the .gui flag of merge-tools (plus another boolean for
  >  vimdiff-like tools.)
  
  
  The option is still there.
  
  The difference between core commands and extdiff commands here is core commands has
  `pager.attend-*` set to True by default. But extdiff commands have `attend-*` set to
  `False` to not cause surprises.
  
  To be consistent, we can enable pager by default and allow it to be disabled via
  `attend-*` configs, just like core hg commands. Since we have already BC on "log"
  (default changed from not using pager to use pager), I think it's okay to BC here.
  That looks cleaner than adding more config flags?
  
  > Alternatively, we could resurrect the global pager.attend-* support, but perhaps there
  >  would be a reason not to?
  
  One reason for not doing command-level pager is a "command" is conceptually bigger than
  "page content". ex. users may want pager for `shelve -l` / `bookmark`, but not `shelve` /
  `bookmark foo`.

REPOSITORY
  rHG Mercurial

REVISION DETAIL
  https://phab.mercurial-scm.org/D803

To: quark, #hg-reviewers, yuja
Cc: yuja, indygreg, mercurial-devel