patch 8.0.0034

Problem:    No completion for ":messages".
Solution:   Complete "clear" argument. (Hirohito Higashi)

src/ex_docmd.c

@@ -4281,6 +4281,11 @@ set_one_cmd_context(
 	    xp->xp_pattern = arg;
 	    break;
 
+	case CMD_messages:
+	    xp->xp_context = EXPAND_MESSAGES;
+	    xp->xp_pattern = arg;
+	    break;
+
 #if defined(FEAT_CMDHIST)
 	case CMD_history:
 	    xp->xp_context = EXPAND_HISTORY;
@@ -5893,6 +5898,7 @@ static struct
 #endif
     {EXPAND_MAPPINGS, "mapping"},
     {EXPAND_MENUS, "menu"},
+    {EXPAND_MESSAGES, "messages"},
     {EXPAND_OWNSYNTAX, "syntax"},
 #if defined(FEAT_PROFILE)
     {EXPAND_SYNTIME, "syntime"},
@@ -11901,6 +11907,18 @@ get_behave_arg(expand_T *xp UNUSED, int idx)
 	return (char_u *)"xterm";
     return NULL;
 }
+
+/*
+ * Function given to ExpandGeneric() to obtain the possible arguments of the
+ * ":messages {clear}" command.
+ */
+    char_u *
+get_messages_arg(expand_T *xp UNUSED, int idx)
+{
+    if (idx == 0)
+	return (char_u *)"clear";
+    return NULL;
+}
 #endif
 
 #ifdef FEAT_AUTOCMD