PATCH: _tar, again

[Peter Stephenson <pws@xxxxxxxxxxxxxxxxx>]

Peter Stephenson wrote:
> - in principle, you can have combined short arguments like -xv or -cP or
> whatever anywhere on the command line before the file list, so it probably
> ought to check if it had no luck early on --- e.g. look for
> -[[:alpha:]]#[cxturA]*

actually, this was pretty much handled and I didn't notice.

> - any --use-compress-program=*, or indeed --use-comp*, should get added to
> $largs
> 
> - any --dir*=* should be changed to when completing archives and existing
> files, which is another good argument for using absolute paths for $tf.

actually, this should only be done for putting files inside the archive,
not for the archive itself.

This handles these and fixes some bugs: finding the archive didn't work if
there were --*'s because it miscounted words; the files inside the archive
were used even for creating an archive (if that was deliberate, there are
probably better ways of persuading the user not to overwrite an existing
archive).

Minor gripes: in the listing, _long_options doesn't show the / after
directories inside the archive as my original _tar did (that's why I stuck
it on the end instead of treating it as a suffix); _path_files seems to
have forgotten about noglobdots somehow.  Somehow my _match_pattern isn't
having an effect on _multi_parts, but I suppose that's my problem.

--- ./Completion/User/_tar.bak	Mon Mar  8 14:59:18 1999
+++ ./Completion/User/_tar	Mon Mar  8 15:24:06 1999
@@ -16,7 +16,7 @@
 emulate -LR zsh
 setopt extendedglob
 
-local _tar_cmd tf tmp
+local _tar_cmd tf tmp del
 
 # First we collect in `_tar_cmd' single letter options describing what
 # should be done with the archive and if it is compressed. This
@@ -32,7 +32,19 @@
 (( $words[(I)--list] ))          && _tar_cmd="t$_tar_cmd"
 (( $words[(I)--(extract|get)] )) && _tar_cmd="x$_tar_cmd"
 (( $words[(I)--create] ))        && _tar_cmd="c$_tar_cmd"
-[[ "$words[2]" != -* ]]          && _tar_cmd="$words[2]$_tar_cmd"
+
+# Other ways of finding out what we're doing:  first
+# look in the first argument if it's not an option
+if [[ "$words[2]" = *[txcdruA]*~-* ]]; then
+  _tar_cmd="$words[2]$_tar_cmd"
+elif [[ $_tar_cmd != *[txcdruA]* && CURRENT -gt 2 ]]; then
+  # look for more obscure long options: these aren't all handled.
+  (( $words[(I)--(diff|compare)] )) && _tar_cmd="d$_tar_cmd"
+  (( $words[(I)--append] )) && _tar_cmd="r$_tar_cmd"
+  (( $words[(I)--update] )) && _tar_cmd="u$_tar_cmd"
+  (( $words[(I)--(con|)catenate] )) && _tar_cmd="A$_tar_cmd"
+  (( $words[(I)--delete] )) && del=1
+fi
 
 # Next, we try to find the archive name and store it in `tf'. The name 
 # is searched after a `--file=' long option, in the third word if the
@@ -47,7 +59,7 @@
   tf="$words[3]"
   _tar_cmd="f$_tar_cmd"
 else
-  tmp="${${(@M)words:#-[^-]*}[(I)*f*]}"
+  tmp="${words[(I)-*f*~--*]}"
   if (( tmp )); then
     tf="$words[tmp+1]"
     _tar_cmd="f$_tar_cmd"
@@ -73,7 +85,7 @@
 
   _tar_archive
 
-elif [[ -n "$_tar_cmd" && -n "$tf" ]]; then
+elif [[ ( "$_tar_cmd" = *[xt]* || -n $del ) && -n "$tf" ]]; then
 
   # ...and files from the archive if we found an archive name and tar
   # commands. We run `tar t...' on the file, keeping the list of
@@ -82,8 +94,15 @@
 
   local largs=-tf
 
-  [[ $_tar_cmd = *z* ]] && largs=-tzf
-  [[ $_tar_cmd = *Z* ]] && largs=-tZf
+  if [[ $_tar_cmd = *z* ]]; then
+    largs=-tzf
+  elif [[ $_tar_cmd = *Z* ]]; then
+    largs=-tZf
+  else
+    # Some random compression program e.g. bzip2
+    tmp="${words[(r)--use-comp*]}"
+    [[ -n $tmp ]] && largs=($tmp -tf)
+  fi
 
   if [[ $tf != $_tar_cache_name ]]; then
     _tar_cache_list=("${(@f)$($words[1] $largs $tf)}")
@@ -91,4 +110,16 @@
   fi
 
   _multi_parts / _tar_cache_list
+else
+  
+  # See if we should use a path prefix.  We have to use eval as the dir can
+  # be any unevaluated thing which appears on the command line, including a
+  # parameter.
+  tmp=${words[(r)--dir[a-z]#=*]}
+  if [[ -n $tmp ]]; then
+    eval "tmp=(${tmp#*=})"
+    _path_files -W tmp
+  else
+    _files
+  fi
 fi

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