Fixes this bug:

    Command line completion for shell commands: "cat </tmp/file" doesn't
    complete, start the file name at the "<".

Solution:  Treat all characters that are invalid file name characters the same
way as white space.  vim_isfilec() is the judge.

Created by Martin Toft <mt@martintoft.dk> during Google Summer of Code 2007.


Index: src/ex_docmd.c
===================================================================
RCS file: /cvsroot/vim/vim7/src/ex_docmd.c,v
retrieving revision 1.129
diff -c -r1.129 ex_docmd.c
*** src/ex_docmd.c	11 Aug 2007 14:00:04 -0000	1.129
--- src/ex_docmd.c	14 Aug 2007 02:01:34 -0000
***************
*** 3281,3286 ****
--- 3281,3287 ----
  
      if (ea.argt & XFILE)
      {
+ 	int c;
  	int in_quote = FALSE;
  	char_u *bow = NULL;	/* Beginning of word */
  
***************
*** 3289,3319 ****
  	 * being expanded.
  	 */
  	xp->xp_pattern = skipwhite(arg);
! 	for (p = xp->xp_pattern; *p; )
  	{
! 	    if (*p == '\\' && p[1] != NUL)
  		++p;
  #ifdef SPACE_IN_FILENAME
! 	    else if (vim_iswhite(*p) && (!(ea.argt & NOSPC) || usefilter))
  #else
! 	    else if (vim_iswhite(*p))
  #endif
  	    {
! 		p = skipwhite(p);
  		if (in_quote)
  		    bow = p;
  		else
  		    xp->xp_pattern = p;
! 		--p;
! 	    }
! 	    else if (*p == '`')
! 	    {
! 		if (!in_quote)
! 		{
! 		    xp->xp_pattern = p;
! 		    bow = p + 1;
! 		}
! 		in_quote = !in_quote;
  	    }
  	    mb_ptr_adv(p);
  	}
--- 3290,3344 ----
  	 * being expanded.
  	 */
  	xp->xp_pattern = skipwhite(arg);
! 	p = xp->xp_pattern;
! 	while (*p != NUL)
  	{
! #ifdef FEAT_MBYTE
! 	    if (has_mbyte)
! 		c = mb_ptr2char(p);
! 	    else
! #endif
! 		c = *p;
! 	    if (c == '\\' && p[1] != NUL)
  		++p;
+ 	    else if (c == '`')
+ 	    {
+ 		if (!in_quote)
+ 		{
+ 		    xp->xp_pattern = p;
+ 		    bow = p + 1;
+ 		}
+ 		in_quote = !in_quote;
+ 	    }
  #ifdef SPACE_IN_FILENAME
! 	    else if (!vim_isfilec(c) && (!(ea.argt & NOSPC) || usefilter))
  #else
! 	    else if (!vim_isfilec(c))
  #endif
  	    {
! 		while (*p != NUL)
! 		{
! #ifdef FEAT_MBYTE
! 		    if (has_mbyte)
! 			c = mb_ptr2char(p);
! 		    else
! #endif
! 			c = *p;
! 		    if (c == '`' || vim_isfilec(c))
! 			break;
! #ifdef FEAT_MBYTE
! 		    if (has_mbyte)
! 			len = (*mb_ptr2len)(p);
! 		    else
! #endif
! 			len = 1;
! 		    mb_ptr_adv(p);
! 		}
  		if (in_quote)
  		    bow = p;
  		else
  		    xp->xp_pattern = p;
! 		p -= len;
  	    }
  	    mb_ptr_adv(p);
  	}