[PATCH] Save more readline state when running compgen

[Grisha Levit]

Completion state is not fully restored after invoking `compgen' within
a competition function.
Normally, if a compspec does not specifically include one of the
options that triggers filename completion, the generated completions
are not treated as filenames:

$ complete -W '/tmp /var' cmd
$ cmd /[TAB]
/tmp /var

However, if a completion function is invoked, and that function
happens to call `compgen' with one of the options that triggers
filename completion, the generated completions _are_ treated as
filenames (i.e. get quoted, have `/' appended to directories, etc.)

$ fun() { compgen -f >/dev/null; }
$ complete -W '/tmp /var' -F fun cmd
$ cmd /[TAB]
tmp/ var/

----

diff --git a/builtins/complete.def b/builtins/complete.def
index 0d9b9293..37eb20ba 100644
--- a/builtins/complete.def
+++ b/builtins/complete.def
@@ -650,7 +650,7 @@ compgen_builtin (WORD_LIST *list)
   STRINGLIST *sl;
   char *word, **matches;
   char *old_line;
-  int old_ind;
+  int old_ind, old_completion, old_quoting, old_suppress;

   if (list == 0)
     return (EXECUTION_SUCCESS);
@@ -692,6 +692,10 @@ compgen_builtin (WORD_LIST *list)

   rval = EXECUTION_FAILURE;

+  old_completion = rl_filename_completion_desired;
+  old_quoting = rl_filename_quoting_desired;
+  old_suppress = rl_completion_suppress_append;
+
   /* probably don't have to save these, just being safe */
   old_line = pcomp_line;
   old_ind = pcomp_ind;
@@ -720,6 +724,10 @@ compgen_builtin (WORD_LIST *list)
       strvec_dispose (matches);
     }

+  rl_filename_completion_desired = old_completion;
+  rl_filename_quoting_desired = old_quoting;
+  rl_completion_suppress_append = old_suppress;
+
   if (sl)
     {
       if (sl->list && sl->list_len)