pager: add attend-<command> option

This lets users override attend settings locally on a command
granularity.

hgext/pager.py

@@ -1,156 +1,168 b''
 # pager.py - display output using a pager
 #
 # Copyright 2008 David Soria Parra <[e-mail]>
 #
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2 or any later version.
 #
 # To load the extension, add it to your configuration file:
 #
 #   [extension]
 #   pager =
 #
 # Run "hg help pager" to get info on configuration.
 
 '''browse command output with an external pager
 
 To set the pager that should be used, set the application variable::
 
   [pager]
   pager = less -FRX
 
 If no pager is set, the pager extensions uses the environment variable
 $PAGER. If neither pager.pager, nor $PAGER is set, no pager is used.
 
 You can disable the pager for certain commands by adding them to the
 pager.ignore list::
 
   [pager]
   ignore = version, help, update
 
 You can also enable the pager only for certain commands using
 pager.attend. Below is the default list of commands to be paged::
 
   [pager]
   attend = annotate, cat, diff, export, glog, log, qdiff
 
 Setting pager.attend to an empty value will cause all commands to be
 paged.
 
 If pager.attend is present, pager.ignore will be ignored.
 
+Lastly, you can enable and disable paging for individual commands with
+the attend-<command> option. This setting takes precedence over
+existing attend and ignore options and defaults::
+
+  [pager]
+  attend-cat = false
+
 To ignore global commands like :hg:`version` or :hg:`help`, you have
 to specify them in your user configuration file.
 
 The --pager=... option can also be used to control when the pager is
 used. Use a boolean value like yes, no, on, off, or use auto for
 normal behavior.
+
 '''
 
 import atexit, sys, os, signal, subprocess, errno, shlex
 from mercurial import commands, dispatch, util, extensions, cmdutil
 from mercurial.i18n import _
 
 testedwith = 'internal'
 
 def _pagerfork(ui, p):
     if not util.safehasattr(os, 'fork'):
         sys.stdout = util.popen(p, 'wb')
         if ui._isatty(sys.stderr):
             sys.stderr = sys.stdout
         return
     fdin, fdout = os.pipe()
     pid = os.fork()
     if pid == 0:
         os.close(fdin)
         os.dup2(fdout, sys.stdout.fileno())
         if ui._isatty(sys.stderr):
             os.dup2(fdout, sys.stderr.fileno())
         os.close(fdout)
         return
     os.dup2(fdin, sys.stdin.fileno())
     os.close(fdin)
     os.close(fdout)
     try:
         os.execvp('/bin/sh', ['/bin/sh', '-c', p])
     except OSError, e:
         if e.errno == errno.ENOENT:
             # no /bin/sh, try executing the pager directly
             args = shlex.split(p)
             os.execvp(args[0], args)
         else:
             raise
 
 def _pagersubprocess(ui, p):
     pager = subprocess.Popen(p, shell=True, bufsize=-1,
                              close_fds=util.closefds, stdin=subprocess.PIPE,
                              stdout=sys.stdout, stderr=sys.stderr)
 
     stdout = os.dup(sys.stdout.fileno())
     stderr = os.dup(sys.stderr.fileno())
     os.dup2(pager.stdin.fileno(), sys.stdout.fileno())
     if ui._isatty(sys.stderr):
         os.dup2(pager.stdin.fileno(), sys.stderr.fileno())
 
     @atexit.register
     def killpager():
         if util.safehasattr(signal, "SIGINT"):
             signal.signal(signal.SIGINT, signal.SIG_IGN)
         pager.stdin.close()
         os.dup2(stdout, sys.stdout.fileno())
         os.dup2(stderr, sys.stderr.fileno())
         pager.wait()
 
 def _runpager(ui, p):
     # The subprocess module shipped with Python <= 2.4 is buggy (issue3533).
     # The compat version is buggy on Windows (issue3225), but has been shipping
     # with hg for a long time.  Preserve existing functionality.
     if sys.version_info >= (2, 5):
         _pagersubprocess(ui, p)
     else:
         _pagerfork(ui, p)
 
 def uisetup(ui):
     if '--debugger' in sys.argv or not ui.formatted():
         return
 
     def pagecmd(orig, ui, options, cmd, cmdfunc):
         p = ui.config("pager", "pager", os.environ.get("PAGER"))
         usepager = False
         always = util.parsebool(options['pager'])
         auto = options['pager'] == 'auto'
 
         if not p:
             pass
         elif always:
             usepager = True
         elif not auto:
             usepager = False
         else:
             attend = ui.configlist('pager', 'attend', attended)
             ignore = ui.configlist('pager', 'ignore')
             cmds, _ = cmdutil.findcmd(cmd, commands.table)
 
             for cmd in cmds:
+                var = 'attend-%s' % cmd
+                if ui.config('pager', var):
+                    usepager = ui.configbool('pager', var)
+                    break
                 if (cmd in attend or
                      (cmd not in ignore and not attend)):
                     usepager = True
                     break
 
         if usepager:
             ui.setconfig('ui', 'formatted', ui.formatted(), 'pager')
             ui.setconfig('ui', 'interactive', False, 'pager')
             if util.safehasattr(signal, "SIGPIPE"):
                 signal.signal(signal.SIGPIPE, signal.SIG_DFL)
             _runpager(ui, p)
         return orig(ui, options, cmd, cmdfunc)
 
     extensions.wrapfunction(dispatch, '_runcommand', pagecmd)
 
 def extsetup(ui):
     commands.globalopts.append(
         ('', 'pager', 'auto',
          _("when to paginate (boolean, always, auto, or never)"),
          _('TYPE')))
 
 attended = ['annotate', 'cat', 'diff', 'export', 'glog', 'log', 'qdiff']