Re: Remaining zsh3.0-pre2 bugs

[Zoltan Hidvegi <hzoli@cs.elte.hu>]

Bart and Zefram discussing a loop in get_comp_string:
> } >Anyway, cs decrements down to 8 because of the two \230 in qword; but
> } >"echo 'a;b'" of course has 10 characters.
> } 
> } Bingo.  That loop has special code for handling backslashes, but not
> } quotes.  I think it needs to handle quotes too.

There is nothing wrong with get_comp_string here.  It works well if there
is just one line containing embeded newlines and quotes etc.  The problem
starts when we are in a multi-line command structure.

[...]
> But that doesn't work for completions with embedded newlines, even when
> a successful completion is possible:
> 
> zagzig<4> touch c'
> > 'dfoo
> zagzig<5> echo c'
> > 'd<TAB>			<-- fails to complete
> 
> I suspect it fails because newline is the only character that can never
> be escaped with a backslash.

It fails because zsh sees that the current word starts in the previous
already entered line.  In that case zsh simply gives up the completion
attempt, restores the original line and returns.  Unfortunately the cursor
position is not always restored correctly.  The patch below fixes that.

The other problem is this:

hzoli /l/src/zsh-RCS % echo '
quote> ' a' 'b<TAB>

hzoli /l/src/zsh-RCS % echo '
quote> ' a\ bfoo 'b            <-- cursor is under the quote preceeding `b'

That is because the changes made by get_comp_string are destroyed.

> And it's broken even for completions with spaces in some circumstances:
> 
> zagzig<6> echo a' '<TAB>
> zagzig<6> echo a\ bfo o		<-- cursor is over the second `o'

And that's a third problem caused by that code:

-     /* When completing between words, the contents *
-      * of wb and we may be garbled.                */
-     if (we > wb && iblank(line[we - 1]) && 
- 	(we < 2 || (line[we - 2] != '\\' && line[we - 2] != STOUC(Meta))))
- 	we--;

I do not know what it meant to fix but I hope it is no longer necessary.
This should be handled in get_comp_string.  get_comp_string changed a lot
since 2.5 so I think it's best to remove this.

And there is one more bug when push-line-or-edit is used:

hzoli /l/src/zsh-RCS % echo '
quote>'<push-line-or-edit>
hwget called with no words.
hzoli /l/src/zsh-RCS % echo '
'

The debug message above only appears after my recent here-document patch.
That is fixed by the one-line patch to lex.c below.

Zoltan


*** Src/zle_tricky.c	1996/07/06 18:17:13	2.56
--- Src/zle_tricky.c	1996/07/09 01:00:32
***************
*** 497,503 ****
  docomplete(int lst)
  {
      char *s, *ol;
!     int olst = lst, chl = 0, ne = noerrs;
  
      /* If we are doing a menu-completion... */
  
--- 497,503 ----
  docomplete(int lst)
  {
      char *s, *ol;
!     int olst = lst, chl = 0, ne = noerrs, ocs;
  
      /* If we are doing a menu-completion... */
  
***************
*** 529,534 ****
--- 529,535 ----
  	char *p, *q;
  
  	ol = dupstring((char *)line);
+ 	ocs = cs;
  	/* Make sure that chline is zero-terminated. */
  	*hptr = '\0';
  	/* Calculate the length of chline. */
***************
*** 550,571 ****
  	    }
  	    *q++ = *p;
  	}
! 	/* Put a zero byte after it and append the original line contents. */
! 	*q = '\0';
! 	strcat((char *)line, ol);
! 	/* Finally remove quoted newlines and replace non-quoted newlines *
! 	 * with semicolons.  This second thing isn't really correct (e.g. *
! 	 * if the command separated by the newlines were actually         *
! 	 * connected with a pipe), but the effect in the completion code  *
! 	 * is the same.                                                   */
! 	for (p = (char *)line; *p; p++)
! 	    if (*p == '\n')
! 		if (p > (char *) line && p[-1] == '\\')
! 		    p[-1] = *p = ' ';
! 		else
! 		    *p = ';';
! 	/* Now make sure that the cursor position variable and the *
! 	 * line length stored in ll are correct.                   */
  	cs += chl;
  	ll = strlen((char *)line);
      }
--- 551,558 ----
  	    }
  	    *q++ = *p;
  	}
! 	/* Append the original line contents. */
! 	strcpy(q, ol);
  	cs += chl;
  	ll = strlen((char *)line);
      }
***************
*** 577,587 ****
      noerrs = 1;
      s = get_comp_string();
      noerrs = ne;
-     /* When completing between words, the contents *
-      * of wb and we may be garbled.                */
-     if (we > wb && iblank(line[we - 1]) && 
- 	(we < 2 || (line[we - 2] != '\\' && line[we - 2] != STOUC(Meta))))
- 	we--;
      /* For vi mode, reset the start-of-insertion pointer to the beginning *
       * of the word being completed, if it is currently later.  Vi itself  *
       * would never change the pointer in the middle of an insertion, but  *
--- 564,569 ----
***************
*** 591,605 ****
  	viinsbegin = ztrsub((char *) line + wb, (char *) line);
      /* If we added chline to the line buffer, reset the original contents. */
      if (ol) {
- 	strcpy((char *) line, ol);
- 	ll = strlen((char *) line);
  	cs -= chl;
  	wb -= chl;
  	we -= chl;
! 	if (wb < 0 || we < 0) {
  	    unmetafy_line();
  	    return;
  	}
      }
      freeheap();
      /* Save the lexer state, in case the completion code uses the lexer *
--- 573,592 ----
  	viinsbegin = ztrsub((char *) line + wb, (char *) line);
      /* If we added chline to the line buffer, reset the original contents. */
      if (ol) {
  	cs -= chl;
  	wb -= chl;
  	we -= chl;
! 	if (wb < 0 || we < 0 || cs < 0) {
! 	    strcpy((char *) line, ol);
! 	    ll = strlen((char *) line);
! 	    cs = ocs;
  	    unmetafy_line();
  	    return;
  	}
+ 	ocs = cs;
+ 	cs = 0;
+ 	foredel(chl);
+ 	cs = ocs;
      }
      freeheap();
      /* Save the lexer state, in case the completion code uses the lexer *
*** Src/lex.c	1996/07/08 01:56:51	2.32
--- Src/lex.c	1996/07/08 23:54:52
***************
*** 180,186 ****
  	return;
      do
  	tok = gettok();
!     while (tok != ENDINPUT && exalias());
      if (tok == NEWLIN || tok == ENDINPUT) {
  	while (hdocs) {
  	    struct heredocs *next = hdocs->next;
--- 180,186 ----
  	return;
      do
  	tok = gettok();
!     while (tok != ENDINPUT && !errflag && exalias());
      if (tok == NEWLIN || tok == ENDINPUT) {
  	while (hdocs) {
  	    struct heredocs *next = hdocs->next;