Re: PATCH: prompt memory handling is screwy

[Peter Stephenson <pws@csr.com>]

On Fri, 24 Oct 2008 11:24:48 +0100
Peter Stephenson <pws@csr.com> wrote:
> Some idiot added a new feature recently that let the prompt code
> be called recursively.  Currently the prompt code isn't written to
> be called recursively, but luckily that's a fairly straightforward
> change, if boring to rename all the variables.

Here's a test.  This is actually more hairy even than the fix:  since I'm
testing directory handling I need to output directories and remove the
bits of the path that vary.  Hence if it fails it may well be the test, not
the shell.  This was giving segmentation violations before the patch.

Index: Test/D01prompt.ztst
===================================================================
RCS file: /cvsroot/zsh/zsh/Test/D01prompt.ztst,v
retrieving revision 1.4
diff -u -r1.4 D01prompt.ztst
--- Test/D01prompt.ztst	26 Sep 2008 09:11:30 -0000	1.4
+++ Test/D01prompt.ztst	24 Oct 2008 13:33:06 -0000
@@ -147,3 +147,57 @@
 >~[scuzzy]/rubbish
 >~mydir/foo
 ?(eval):33: no directory expansion: ~[scuzzy]
+
+  (
+  zsh_directory_name() {
+  emulate -L zsh
+  setopt extendedglob
+  local -a match mbegin mend
+  if [[ $1 = n ]]; then
+      if [[ $2 = *:l ]]; then
+	  reply=(${2%%:l}/very_long_directory_name)
+	  return 0
+      else
+	  return 1
+      fi
+  else
+      if [[ $2 = (#b)(*)/very_long_directory_name ]]; then
+	reply=(${match[1]}:l ${#2})
+	return 0
+      else
+	return 1
+      fi
+  fi
+  }
+  parent=$PWD
+  dir=$parent/very_long_directory_name
+  mkdir $dir
+  cd $dir
+  fn() {
+     PS4='+%N:%i> '
+     setopt localoptions xtrace
+     # The following is the key to the test.
+     # It invokes zsh_directory_name which does PS4 output stuff
+     # while we're doing prompt handling for the parameter
+     # substitution.  This checks recursion works OK.
+     local d=${(%):-%~}
+     print ${d//$parent/\<parent\>}
+  }
+  fn 2>stderr
+  # post process error to remove variable contents
+  while read line; do
+    # tricky: reply is set to include directory length which is variable
+    [[ $line = *reply* ]] && continue
+    print ${line//$parent/\<parent\>}
+  done <stderr >&2
+  )
+0:Recursive use of prompts
+>~[<parent>:l]
+?+zsh_directory_name:1> emulate -L zsh
+?+zsh_directory_name:2> setopt extendedglob
+?+zsh_directory_name:3> local -a match mbegin mend
+?+zsh_directory_name:4> [[ d == n ]]
+?+zsh_directory_name:12> [[ <parent>/very_long_directory_name == (#b)(*)/very_long_directory_name ]]
+?+zsh_directory_name:14> return 0
+?+fn:7> local 'd=~[<parent>:l]'
+?+fn:8> print '~[<parent>:l]'

-- 
Peter Stephenson <pws@csr.com>                  Software Engineer
CSR PLC, Churchill House, Cambridge Business Park, Cowley Road
Cambridge, CB4 0WZ, UK                          Tel: +44 (0)1223 692070