Re: still confused about completion and matching

[Sven Wischnowsky <wischnow@xxxxxxxxxxxxxxxxxxxxxxx>]

E. Jay Berkenbilt wrote:

> ...
> 
> If I omit "suffix" from :completion:*:paths expand, although 
> 
> ls u?/ TAB
> 
> doesn't generate a superfluous / anymore,
> 
> ls u?/q/ TAB
> 
> still does.

This is a different case. These are the automatically added slashes we
get due to LIST_TYPES. I've got a patch for the C-code to fix it there.
I'll commit it. We won't want it to ever add a file-type character 
after a slash anyway or do we?

> ls u?/q/d TAB
> 
> lists u1/q/devel and u3/q/dark as it should.  However,
> 
> ls u?/q/de TAB
> 
> doesn't list anything.  Similarly,

As you found out, this happened in cases where there was only one match.
This was caused by the yet unchanged compadd around line 624 in _path_files
which used pattern matching even if there was a pattern in a component in
the -p-prefix (which is used using the match specs).

> ...
> 
> Finally,
> 
> ls u? TAB
> 
> works fine, but
> 
> ls ./u? TAB
> 
> makes the ? disappear from the commandline.

A small problem with an attempt at additional cleverness in _match.

> ...
> 
> Now to make a gratuitous personal observation.... zsh is about the
> only open source software I've used recently where it hasn't been just
> as easy for me to send a patch implementing my requested changes as it
> is to describe them in detail.  I'm not sure exactly why this is, but
> I think it's just because there is so much power that can be expressed
> so compactly that the density of code that I don't understand due to
> lack of zsh knowledge is increased.  Perhaps also the software has so
> much potential that I'm thinking of changes that just wouldn't occur
> to me if the software couldn't already almost handle them. 

I sometimes have the impression that this is a trap even we've run
into before ;-)

> I have a
> rule against modifying code I don't understand (at least locally).
> Reading the code in the zsh completion system, I find that there is
> something mysterious in just about every line though the documentation
> seems remarkably complete.  Should I decide to spend the time required
> to really understand what's going on in code like that in _path_files,
> looking back at these discussions and patches will no doubt be an
> invaluable tool. 

_path_files certainly wasn't the best starting point when trying to
learn the ways of the completion system. Writing a new completion
function, looking at older ones, starting with a simple and incomplete
solution and improving it step by step is almost certainly the best
way. As Andrej already said, you should begin by using only _arguments,
continue by using its advanced features as you go along, using (i.e.
calling) other utility functions if needed (I'm referring to functions
like _hosts, for which we still don't have a complete list, sigh). If
needed, you could then have a look at the compadd and compset builtins
and the special completion parameters (and from those $compstate is
normally the last one needed). And if your completion function can
reasonably support different modes, learn using zstyle to look up
styles.



Bye
 Sven

diff -u -r ../oz/Completion/Builtins/_zstyle ./Completion/Builtins/_zstyle
--- ../oz/Completion/Builtins/_zstyle	Sun Oct 22 15:17:57 2000
+++ ./Completion/Builtins/_zstyle	Mon Oct 23 19:28:26 2000
@@ -44,7 +44,7 @@
   ignored-patterns	 c:
   insert-ids             c:insert-ids
   insert-tab             c:bool
-  insert-unambiguous	 c:bool
+  insert-unambiguous	 c:insunambig
   keep-prefix		 c:keep-prefix
   last-prompt		 c:bool
   list			 c:listwhen
@@ -52,6 +52,7 @@
   list-packed		 c:bool
   list-prompt            c:
   list-rows-first	 c:bool
+  list-suffixes		 c:bool
   local			 c:
   match-original	 c:match-orig
   matcher		 c:
@@ -290,6 +291,10 @@
 
     oldmatches) 
       _wanted values expl 'use list of old matches' compadd true false only
+      ;;
+
+    insunambig) 
+      _wanted values expl 'insert unambiguous string compadd true false pattern
       ;;
 
     urgh) 
diff -u -r ../oz/Completion/Core/_match ./Completion/Core/_match
--- ../oz/Completion/Core/_match	Sun Oct 22 15:17:57 2000
+++ ./Completion/Core/_match	Mon Oct 23 20:33:15 2000
@@ -11,41 +11,56 @@
 
 ### Shouldn't be needed any more: [[ _matcher_num -gt 1 ]] && return 1
 
-local tmp opm="$compstate[pattern_match]" ret=0 orig ins
+local tmp opm="$compstate[pattern_match]" ret=1 orig ins
+local oms="$_old_match_string"
+local ocsi="$compstate[insert]" ocspi="$compstate[pattern_insert]"
 
 # Do nothing if we don't have a pattern.
 
 tmp="${${:-$PREFIX$SUFFIX}#[~=]}"
 [[ "$tmp:q" = "$tmp" ]] && return 1
 
+_old_match_string="$PREFIX$SUFFIX$HISTNO"
+
 zstyle -s ":completion:${curcontext}:" match-original orig
-zstyle -b ":completion:${curcontext}:" insert-unambiguous ins
+zstyle -s ":completion:${curcontext}:" insert-unambiguous ins
 
 # Try completion without inserting a `*'?
 
 if [[ -n "$orig" ]]; then
   compstate[pattern_match]='-'
-  _complete && ret=1
+  _complete && ret=0
   compstate[pattern_match]="$opm"
 
-  if (( ret )); then
-    [[ "$ins" = yes &&
-       $#compstate[unambiguous] -ge ${#:-${PREFIX}${SUFFIX}} ]] && 
-        compstate[pattern_insert]=unambiguous
-    return 0
-  fi
+  # No completion with inserting `*'?
+
+  [[ ret -eq 1 && "$orig" = only ]] && return 1
+fi
+
+if (( ret )); then
+  compstate[pattern_match]='*'
+  _complete && ret=0
+  compstate[pattern_match]="$opm"
 fi
 
-# No completion with inserting `*'?
+if (( ! ret )); then
+
+  if [[ "$ins" = pattern && $compstate[nmatches] -gt 1 ]]; then
 
-[[ "$orig" = only ]] && return 1
+    [[ "$oms" = "$PREFIX$SUFFIX$HISTNO" &&
+       "$compstate[insert]" = automenu-unambiguous ]] &&
+        compstate[insert]=automenu
+    [[ "$compstate[insert]" != *menu ]] &&
+        compstate[pattern_insert]= compstate[insert]=
 
-compstate[pattern_match]='*'
-_complete && ret=1
-compstate[pattern_match]="$opm"
+    [[ $compstate[unambiguous_cursor] -gt $#compstate[unambiguous] ]] &&
+        ins=yes compstate[insert]="$ocsi" compstate[pattern_insert]="$ocspi"
+  fi
 
-[[ ret -eq 1 && "$ins" = yes &&
-   $#compstate[unambiguous] -ge ${#:-${PREFIX}${SUFFIX}} ]] && 
-    compstate[pattern_insert]=unambiguous
+  [[ "$ins" = (true|yes|on|1) &&
+     $#compstate[unambiguous] -ge ${#:-${PREFIX}${SUFFIX}} ]] && 
+      compstate[pattern_insert]=unambiguous
+
+fi
 
-return 1-ret
+return ret
diff -u -r ../oz/Completion/Core/_path_files ./Completion/Core/_path_files
--- ../oz/Completion/Core/_path_files	Sun Oct 22 15:17:57 2000
+++ ./Completion/Core/_path_files	Mon Oct 23 20:56:33 2000
@@ -5,7 +5,7 @@
 
 local linepath realpath donepath prepath testpath exppath skips skipped
 local tmp1 tmp2 tmp3 tmp4 i orig eorig pre suf tpre tsuf opre osuf cpre
-local pats haspats ignore pfxsfx sopt gopt opt sdirs ignpar cfopt
+local pats haspats ignore pfxsfx sopt gopt opt sdirs ignpar cfopt listsfx
 local nm=$compstate[nmatches] menu matcher mopts sort match mid accex fake
 
 typeset -U prepaths exppaths
@@ -137,6 +137,8 @@
 fi
 
 zstyle -s ":completion:${curcontext}:paths" special-dirs sdirs
+zstyle -t ":completion:${curcontext}:paths" list-suffixes &&
+    listsfx=yes
 
 [[ "$pats" = ((|*[[:blank:]])\*(|[[:blank:]]*)|*\([^[:blank:]]#/[^[:blank:]]#\)*) ]] &&
     sopt=$sopt/
@@ -460,9 +462,11 @@
       SUFFIX="${tsuf}"
     fi
 
-    if (( tmp4 )) ||
-       [[ -n "$compstate[pattern_match]" &&
-          "$tmp2" = (|*[^\\])[][*?#~^\|\<\>]* ]]; then
+    # This once tested `|| [[ -n "$compstate[pattern_match]" &&
+    # "$tmp2" = (|*[^\\])[][*?#~^\|\<\>]* ]]' but it should now be smart
+    # enough to handle multiple components with patterns.
+
+    if (( tmp4 )); then
       # It is. For menucompletion we now add the possible completions
       # for this component with the unambigous prefix we have built
       # and the rest of the string from the line as the suffix.
@@ -480,15 +484,33 @@
         compquote tmp1 tmp2
       fi
 
+      if [[ -z "$_comp_correct" &&
+            "$compstate[pattern_match]" = \*  && -n "$listsfx" &&
+            "$tmp2" = (|*[^\\])[][*?#~^\|\<\>]* ]]; then
+        PREFIX="$opre"
+        SUFFIX="$osuf"
+      fi
+
       if [[ -n $menu || -z "$compstate[insert]" ]] ||
-         ! zstyle -t ":completion:${curcontext}:paths" expand suffix; then
+         ! zstyle -t ":completion:${curcontext}:paths" expand suffix ||
+           [[ -z "$listsfx" &&
+              ( -n "$_comp_correct" ||
+                -z "$compstate[pattern_match]" || "$SUFFIX" != */* ||
+                "${SUFFIX#*/}" = (|*[^\\])[][*?#~^\|\<\>]* ) ]]; then
         (( tmp4 )) && zstyle -t ":completion:${curcontext}:paths" ambiguous &&
             compstate[to_end]=
         if [[ "$tmp3" = */* ]]; then
-	  compadd -Qf "$mopts[@]" -p "$linepath$tmp2" -s "/${tmp3#*/}" \
-	          -W "$prepath$realpath$testpath" \
-		  "$pfxsfx[@]" -M "r:|/=* r:|=*" \
-		  - "${(@)tmp1%%/*}"
+	  if [[ -z "$listsfx" || "$tmp3" != */?* ]]; then
+	    compadd -Qf "$mopts[@]" -p "$linepath$tmp2" -s "/${tmp3#*/}" \
+	            -W "$prepath$realpath$testpath" \
+		    "$pfxsfx[@]" -M "r:|/=* r:|=*" \
+		    - "${(@)tmp1%%/*}"
+          else
+	    compadd -Qf "$mopts[@]" -p "$linepath$tmp2" \
+	            -W "$prepath$realpath$testpath" \
+		    "$pfxsfx[@]" -M "r:|/=* r:|=*" \
+		    - "${(@)^tmp1%%/*}/${tmp3#*/}"
+          fi
 	else
 	  compadd -Qf "$mopts[@]" -p "$linepath$tmp2" \
 	          -W "$prepath$realpath$testpath" \
@@ -497,12 +519,20 @@
 	fi
       else
         if [[ "$tmp3" = */* ]]; then
-	  tmp3=( -Qf "$mopts[@]" -p "$linepath$tmp2"
+	  tmp4=( -Qf "$mopts[@]" -p "$linepath$tmp2"
 	         -W "$prepath$realpath$testpath"
 	         "$pfxsfx[@]" -M "r:|/=* r:|=*" )
-          for i in "$tmp1[@]"; do
-	    compadd "$tmp3[@]" -s "/${i#*/}" - "${i%%/*}"
-	  done
+	  if [[ -z "$listsfx" ]]; then
+            for i in "$tmp1[@]"; do
+	      compadd "$tmp4[@]" -s "/${i#*/}" - "${i%%/*}"
+	    done
+          else
+            [[ -n "$compstate[pattern_match]" ]] && SUFFIX="${SUFFIX:s./.*/}*"
+
+            for i in "$tmp1[@]"; do
+	      compadd "$tmp4[@]" - "$i"
+	    done
+          fi
         else
 	  compadd -Qf "$mopts[@]" -p "$linepath$tmp2" \
                   -W "$prepath$realpath$testpath" \
@@ -526,22 +556,33 @@
     # take it from the filenames.
 
     testpath="${testpath}${tmp1[1]%%/*}/"
-    tmp1=( "${(@)tmp1#*/}" )
 
     tmp3="${tmp3#*/}"
 
     if [[ "$tpre" = */* ]]; then
-      cpre="${cpre}${tpre%%/*}/"
+      if [[ -z "$_comp_correct" && -n "$compstate[pattern_match]" &&
+            "$tmp2" = (|*[^\\])[][*?#~^\|\<\>]* ]]; then
+        cpre="${cpre}${tmp1[1]%%/*}/"
+      else
+        cpre="${cpre}${tpre%%/*}/"
+      fi
       tpre="${tpre#*/}"
     elif [[ "$tsuf" = */* ]]; then
       [[ "$tsuf" != /* ]] && mid="$testpath"
-      cpre="${cpre}${tpre}/"
+      if [[ -z "$_comp_correct" && -n "$compstate[pattern_match]" &&
+            "$tmp2" = (|*[^\\])[][*?#~^\|\<\>]* ]]; then
+        cpre="${cpre}${tmp1[1]%%/*}/"
+      else
+        cpre="${cpre}${tpre}/"
+      fi
       tpre="${tsuf#*/}"
       tsuf=
     else
       tpre=
       tsuf=
     fi
+
+    tmp1=( "${(@)tmp1#*/}" )
   done
 
   if [[ -z "$tmp4" ]]; then
@@ -580,8 +621,14 @@
       else
         compquote tmp4 tmp1
       fi
-      compadd -Qf "$mopts[@]" -p "$linepath$tmp4" -W "$prepath$realpath$testpath" \
-	      "$pfxsfx[@]" -M "r:|/=* r:|=*" -a tmp1
+      if [[ -z "$_comp_correct" && -n "$compstate[pattern_match]" &&
+            "$PREFIX$SUFFIX" = (|*[^\\])[][*?#~^\|\<\>]* ]]; then
+        compadd -Qf -W "$prepath$realpath" "$pfxsfx[@]" "$mopts[@]" \
+                -M "r:|/=* r:|=*" - "$linepath$tmp4${(@)^tmp1}"
+      else
+        compadd -Qf -p "$linepath$tmp4" -W "$prepath$realpath$testpath" \
+	        "$pfxsfx[@]" "$mopts[@]" -M "r:|/=* r:|=*" -a tmp1
+      fi
     fi
   fi
 done
diff -u -r ../oz/Doc/Zsh/compsys.yo ./Doc/Zsh/compsys.yo
--- ../oz/Doc/Zsh/compsys.yo	Sun Oct 22 15:17:51 2000
+++ ./Doc/Zsh/compsys.yo	Mon Oct 23 19:28:27 2000
@@ -1367,6 +1367,10 @@
 in the context name to one of tt(correct-)var(num) or
 tt(approximate-)var(num), where var(num) is the number of errors that
 were accepted.
+
+When used for the tt(_match) completer, the style may also be set to
+the string `tt(pattern)'.  This makes the pattern on the line be left
+unchanged if it didn't match unambiguously.
 )
 kindex(keep-prefix, completion style)
 item(tt(keep-prefix))(
@@ -1466,6 +1470,14 @@
 determines if matches are to be listed in a rows-first fashion, as for the
 tt(LIST_ROWS_FIRST) option.
 )
+kindex(list-suffixes, completion style)
+item(tt(list-suffixes))(
+This style is used by the function used to complete filenames.  If
+completion is attempted on a string containing multiple partially
+typed pathname components and this style is set to `true', all
+components starting with the first one for which more than one match
+could be generated will be shown.
+)
 kindex(local, completion style)
 item(tt(local))(
 This style is used by completion functions which generate URLs as
@@ -2416,6 +2428,9 @@
 tt(insert-unambiguous) style is set to `true'.  In
 this case menu completion will only be started if no unambiguous string
 could be generated that is at least as long as the original string.
+The style may also be set to the string `tt(pattern)'.  This will keep 
+the pattern on the line intact as long as there isn't an unambiguous
+completion with which it could be replaced.
 
 Note that the matcher specifications defined globally or used by the
 completion functions will not be used.
@@ -3474,7 +3489,7 @@
 `tt(-r)', and `tt(-R)' options from the tt(compadd) builtin.
 
 Finally, the tt(_path_files) function  uses the styles tt(expand),
-tt(ambiguous) and tt(special-dirs) and tt(file-sort).
+tt(ambiguous), tt(special-dirs), tt(list-suffixes) and tt(file-sort).
 )
 findex(_regex_arguments)
 item(tt(_regex_arguments) var(name) var(specs) ...)(

--
Sven Wischnowsky                         wischnow@xxxxxxxxxxxxxxxxxxxxxxx