Fix backwards compatibility calls to _known_hosts

This mimics the old behaviour where you could reuse `_known_hosts()' as
a helper function and pass it `-a' or `-c'.
NOTE: Using `_known_hosts' as a helper function and passing options to
`_known_hosts' is deprecated: Use `_known_hosts_real' instead.

bash_completion

@@ -1052,10 +1052,14 @@ shopt -u hostcomplete && complete -F _user_at_host $nospace talk ytalk finger
 #       `_known_hosts_real' instead.
 _known_hosts()
 {
+	local options
 	COMPREPLY=()
 
-	# NOTE: Passing "$@" is deprecated.  See NOTE above.
-	_known_hosts_real "$@" "$(_get_cword)"
+	# NOTE: Using `_known_hosts' as a helper function and passing options
+	#       to `_known_hosts' is deprecated: Use `_known_hosts_real' instead.
+	[ "$1" = -a ] || [ "$2" = -a ] && options=-a
+	[ "$1" = -c ] || [ "$2" = -c ] && options="$options -c"
+	_known_hosts_real $options "$(_get_cword)"
 }
 
 # Helper function for completing _known_hosts.

test/completion/ping.exp

@@ -0,0 +1,3 @@
+if {[assert_bash_type ping]} {
+    source "lib/completions/ping.exp"
+}; # if

test/lib/completions/ping.exp

@@ -0,0 +1,20 @@
+proc setup {} {
+    save_env
+}; # setup()
+
+
+proc teardown {} {
+    assert_env_unmodified
+}; # teardown()
+
+
+setup
+
+
+assert_complete_any "ping "
+
+
+sync_after_int
+
+
+teardown