PATCH: 3.1.5-pws-10: more random completion widgetry

[Peter Stephenson <pws@xxxxxxxxxxxxxxxxx>]

Suppose I'd better try to keep doing my bit for future generations.  Here
are some minor tweaks:

- _builtin didn't handle the remaining arguments properly, it restricted
them to the one after the builtin, so the nested completion didn't work

- _cd now does alles mögliche: complete the second argument to cd (third
word), handle + and - after pushd by listing $(dirs -v) and cycling through
the numbers, so we lazy people can just change directory with lots of tabs
(but you need to type the + or -, hope that's not too much like hard work).

- _most_recent_file: I messed up the tilde checking last time; also, it now
takes a numeric argument so that you can get the Nth most recent, or by
judicious use of negative arguments, oldest file ( Esc - \C-x m).  I hope
Zefram's not going to take exception to $NUMERIC, because it seems to work
extremely well in practice.  I also stuck in a -U to compadd, so that you
can do *.txt\C-xm to get the most recent .txt file.  (Not that much shorter
than *.txt(om[1])<TAB>, I suppose.  But some people don't like arcane
syntax, for some unaccountable reason.)

--- Completion/Builtins/_builtin.bak	Mon Mar  1 13:50:31 1999
+++ Completion/Builtins/_builtin	Wed Mar  3 16:35:57 1999
@@ -1,6 +1,8 @@
 #defcomp builtin
 
-if [[ -position 3 -1 ]]; then
+if (( $CURRENT > 2 )); then
+  shift words
+  (( CURRENT -- ))
   _normal
 else
   compgen -eB
--- Completion/Builtins/_cd.bak	Mon Mar  1 13:54:12 1999
+++ Completion/Builtins/_cd	Wed Mar  3 16:37:01 1999
@@ -1,7 +1,62 @@
-#defcomp cd
+#defcomp cd pushd
 
-if (( $#cdpath )); then
-  _files -W cdpath -/
+# Handling of cd.
+#  - Normally just completes directories.  Uses cdpath if that's set
+#    and the string doesn't begin with ~, /, ./ or ../.
+#  - In the second argument to cd for the form `cd old new', completes
+#    possible `new' strings by examining `old' and $PWD.
+#  - After pushd - or pushd +, completes numbers, but the listing
+#    gives you the list of directories to complete.  This turns on
+#    menu-completion and lists the possibilities automatically, otherwise
+#    it's not a lot of use.  If you don't type the + or - it will
+#    complete directories as normal.
+
+local pushdminus
+[[ -o pushdminus ]] && pushdminus=1
+
+emulate -LR zsh
+setopt extendedglob
+
+if [[ -position 3 ]]; then
+  # cd old new: look for old in $PWD and see what can replace it
+  local rep
+  # Get possible completions using word in position 2
+  rep=(${~PWD/$words[2]/*}~$PWD(-/N))
+  # Now remove all the common parts of $PWD and the completions from this
+  rep=(${${rep#${PWD%%$words[2]*}}%${PWD#*$words[2]}})
+  (( $#rep )) && compadd $rep
+elif [[ $words[1] = pu* && $PREFIX = [-+]* ]]; then
+  # pushd: just complete the numbers, but show the full directory list with
+  # numbers.
+  # For - we do the same thing, but reverse the numbering (other
+  # way round if pushdminus is set).
+  # The test is for pu* because I have an alias pu since I'm too
+  # lazy to type pushd.
+  IPREFIX=$PREFIX[1]
+  PREFIX=$PREFIX[2,-1]
+  local list lines
+  # get the list of directories with their canonical number
+  lines="$(dirs -v)"
+  # turn the lines into an array, removing the current directory
+  list=(${${(f)lines}##0*})
+  if [[ ( $IPREFIX = - && -z $pushdminus ) ||
+        ( $IPREFIX = + && -n $pushdminus ) ]]; then
+    # reverse the numbering: it counts the last one as -0, which
+    # is a little strange.
+    integer tot i
+    for (( i = 1, tot = $#list-1; tot >= 0; i++, tot-- )); do
+      list[$i]="$tot${list[$i]##[0-9]#}"
+    done
+  fi
+  # make sure -y treats this as a single string
+  lines="${(F)list}"
+  # get the array of numbers only
+  list=(${list%%[ 	]*})
+  compgen -y '$lines' -Q -k list
+  [[ -z $compstate[list] ]] && compstate[list]=list
+  [[ -n $compstate[insert] ]] && compstat[insert]=menu
+elif [[ $PREFIX != (\~|/|./|../)* && $#cdpath -ne 0 ]]; then
+  _path_files -W cdpath -/
 else
-  _files -/
+  _path_files -/
 fi
--- Completion/Commands/_most_recent_file.bak	Mon Mar  1 16:34:23 1999
+++ Completion/Commands/_most_recent_file	Wed Mar  3 16:57:51 1999
@@ -1,11 +1,22 @@
 #defkeycomp complete-word \C-xm
+
+# Complete the most recent file matching the pattern on the line so
+# far: globbing is active, i.e. *.txt will be expanded to the most recent
+# file ending in .txt
+#
+# With a prefix argument, select the Nth most recent matching file;
+# negative arguments work in the opposite direction, so for example
+# `Esc - \C-x m' gets you the oldest file.
+#
+# (`Most recent' means most recently modified.)
+
 local file tilde etilde
-if [[ $PREFIX = \~*/ ]]; then
+if [[ $PREFIX = \~*/* ]]; then
   tilde=${PREFIX%%/*}
   etilde=${~tilde}
-  file=($~PREFIX*$~SUFFIX(om[1]N))
+  file=($~PREFIX*$~SUFFIX(om[$NUMERIC]N))
   file=(${file/#$etilde/$tilde})
 else
-  file=($~PREFIX*$~SUFFIX(om[1]N))
+  file=($~PREFIX*$~SUFFIX(om[$NUMERIC]N))
 fi
-(( $#file )) && compadd -f -Q $file
+(( $#file )) && compadd -U -f -Q $file

-- 
Peter Stephenson <pws@xxxxxxxxxxxxxxxxx>       Tel: +39 050 844536
WWW:  http://www.ifh.de/~pws/
Dipartimento di Fisica, Via Buonarroti 2, 56127 Pisa, Italy