Re: complete command doesn't work for files...

[Daniel Jacobowitz <drow@mvista.com>]

First of all, sorry about the long delay.  I've been meaning to look at
this.

On Wed, Sep 24, 2003 at 04:14:05PM -0700, Jim Ingham wrote:
> I was looking at this for some other reason (I want to add an 
> "interpreter-complete console" type command), and I noticed that 
> "complete" and the complete_line function that it relies on don't work 
> when the input text is a filename, and contains more that just the 
> filename.  You can see this easily, do:
> 
> (gdb) file /usr/<TAB><TAB>
> X11R6               etc                 info                local       
>         share
> bin                 games               kerberos            lost+found  
>         src
> dict                i386-glibc21-linux  lib                 man         
>         tmp
> doc                 include             libexec             sbin
> (gdb) complete file /usr/
> (gdb)
> 
> That isn't right, you should get:
> 
> (gdb) complete file /usr/
> file /usr/X11R6
> file /usr/bin
> file /usr/dict
> file /usr/doc
> file /usr/etc
> file /usr/games
> file /usr/i386-glibc21-linux
> file /usr/include
> file /usr/info
> file /usr/kerberos
> file /usr/lib
> file /usr/libexec
> file /usr/local
> file /usr/lost+found
> file /usr/man
> file /usr/sbin
> file /usr/share
> file /usr/src
> file /usr/tmp
> 
> The attached patch fixes the bug.
> 
> The <TAB><TAB> case works because readline advances the first argument 
> of complete_line past the initial command.  But "complete" always 
> passes both TEXT and LINE_BUFFER as the whole command.  This patch 
> actually does what the comment about file completers above it says it 
> intends, namely that we should go to the cursor, and then back up to 
> the first file-wordbreak we find.  The old code clearly didn't do 
> that...  Both the <TAB> case and the complete case work now.  This also 
> makes emacs behave a little better when you try to complete files.
> 
> I added a test case for this failure.

I disagree with your analysis.  The expectation is that readline may
have broken words prematurely for filenames - which it does, sometimes,
see my mail to gdb@ yesterday - but not failed to break words.  So the
caller of complete_line is in error for passing arg.  I imagine it
messes up some of the other completers too.  Also, you didn't fix
"complete file "; it was right next to the comment in question and had
the same problem.

Here's an alternative patch; tested, no regressions, fixes the problem.
I'll commit it in a few days if no one objects.

-- 
Daniel Jacobowitz
MontaVista Software                         Debian GNU/Linux Developer

2004-01-19  Daniel Jacobowitz  <drow@mvista.com>

	* cli/cli-cmds.c: Include readline.h.
	(complete_command): Pass the start of the last word to
	complete_line.

2004-01-19  Daniel Jacobowitz  <drow@mvista.com>

	* gdb.base/completion.exp: Kill a stray backslash.

2004-01-19  Jim Ingham  <jingham@apple.com>

	* gdb.base/completion.exp: Test that "complete file ./gdb.base/compl"
	agrees with the result from sending a tab.

Index: cli/cli-cmds.c
===================================================================
RCS file: /cvs/src/src/gdb/cli/cli-cmds.c,v
retrieving revision 1.37
diff -u -p -r1.37 cli-cmds.c
--- cli/cli-cmds.c	17 Dec 2003 21:47:47 -0000	1.37
+++ cli/cli-cmds.c	19 Jan 2004 16:13:31 -0000
@@ -1,6 +1,6 @@
 /* GDB CLI commands.
 
-   Copyright 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
+   Copyright 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
 
    This file is part of GDB.
 
@@ -20,6 +20,7 @@
    Boston, MA 02111-1307, USA.  */
 
 #include "defs.h"
+#include <readline/readline.h>
 #include <readline/tilde.h>
 #include "completer.h"
 #include "target.h"	 /* For baud_rate, remote_debug and remote_timeout */
@@ -224,7 +225,7 @@ complete_command (char *arg, int from_tt
 {
   int i;
   int argpoint;
-  char **completions;
+  char **completions, *point, *arg_prefix;
 
   dont_repeat ();
 
@@ -232,7 +233,23 @@ complete_command (char *arg, int from_tt
     arg = "";
   argpoint = strlen (arg);
 
-  completions = complete_line (arg, arg, argpoint);
+  /* complete_line assumes that its first argument is somewhere within,
+     and except for filenames at the beginning of, the word to be completed.
+     The following crude imitation of readline's word-breaking tries to
+     accomodate this.  */
+  point = arg + argpoint;
+  while (point > arg)
+    {
+      if (strchr (rl_completer_word_break_characters, point[-1]) != 0)
+        break;
+      point--;
+    }
+
+  arg_prefix = alloca (point - arg + 1);
+  memcpy (arg_prefix, arg, point - arg);
+  arg_prefix[point - arg] = 0;
+
+  completions = complete_line (point, arg, argpoint);
 
   if (completions)
     {
@@ -248,7 +265,7 @@ complete_command (char *arg, int from_tt
       while (item < size)
 	{
 	  int next_item;
-	  printf_unfiltered ("%s\n", completions[item]);
+	  printf_unfiltered ("%s%s\n", arg_prefix, completions[item]);
 	  next_item = item + 1;
 	  while (next_item < size
 		 && ! strcmp (completions[item], completions[next_item]))
Index: testsuite/gdb.base/completion.exp
===================================================================
RCS file: /cvs/src/src/gdb/testsuite/gdb.base/completion.exp,v
retrieving revision 1.20
diff -u -p -r1.20 completion.exp
--- testsuite/gdb.base/completion.exp	13 Jan 2004 23:39:54 -0000	1.20
+++ testsuite/gdb.base/completion.exp	19 Jan 2004 16:13:31 -0000
@@ -657,6 +657,15 @@ gdb_test "cd ${fullsrcdir}" \
          "Working directory [string_to_regexp ${fullsrcdir}].*" \
          "cd to \${srcdir}"
 
+send_gdb "complete file ./gdb.base/compl\n"
+sleep 1
+gdb_expect  {
+    -re "file ./gdb.base/completion\\.exp.*$gdb_prompt $"
+	{ pass "complete-command 'file ./gdb.base/compl'"}
+    -re ".*$gdb_prompt $"       { fail "complete-command 'file ./gdb.base/compl'" }
+    timeout         { fail "(timeout) complete-command 'file ./gdb.base/compl'" }
+}
+
 send_gdb "file ./gdb.base/complet\t"
 sleep 1
 gdb_expect  {
@@ -664,7 +673,6 @@ gdb_expect  {
             { send_gdb "\n"
               gdb_expect {
                       -re "\r\nA program is being debugged already\\.  Kill it\\? \\(y or n\\) $"
-\
                       { send_gdb "n\n"
                         gdb_expect {
                                 -re "\r\nProgram not killed\\.\r\n$gdb_prompt $"\