patch 8.0.0878: no completion for :mapclear

Problem:    No completion for :mapclear.
Solution:   Add completion (Nobuhiro Takasaki et al. closes #1943)

runtime/doc/eval.txt

@@ -4368,6 +4368,7 @@ getcompletion({pat}, {type} [, {filtered}])		*getcompletion()*
 		highlight	highlight groups
 		history		:history suboptions
 		locale		locale names (as output of locale -a)
+		mapclear        buffer argument
 		mapping		mapping name
 		menu		menus
 		messages	|:messages| suboptions

runtime/doc/map.txt

@@ -1279,6 +1279,7 @@ completion can be enabled:
 	-complete=highlight	highlight groups
 	-complete=history	:history suboptions
 	-complete=locale	locale names (as output of locale -a)
+	-complete=mapclear	buffer argument
 	-complete=mapping	mapping name
 	-complete=menu		menus
 	-complete=messages	|:messages| suboptions

src/ex_docmd.c

@@ -4223,6 +4223,19 @@ set_one_cmd_context(
 	case CMD_xunmap:
 	    return set_context_in_map_cmd(xp, cmd, arg, forceit,
 						      FALSE, TRUE, ea.cmdidx);
+	case CMD_mapclear:
+	case CMD_nmapclear:
+	case CMD_vmapclear:
+	case CMD_omapclear:
+	case CMD_imapclear:
+	case CMD_cmapclear:
+	case CMD_lmapclear:
+	case CMD_smapclear:
+	case CMD_xmapclear:
+	    xp->xp_context = EXPAND_MAPCLEAR;
+	    xp->xp_pattern = arg;
+	    break;
+
 	case CMD_abbreviate:	case CMD_noreabbrev:
 	case CMD_cabbrev:	case CMD_cnoreabbrev:
 	case CMD_iabbrev:	case CMD_inoreabbrev:
@@ -5964,6 +5977,7 @@ static struct
 	&& (defined(FEAT_GETTEXT) || defined(FEAT_MBYTE))
     {EXPAND_LOCALES, "locale"},
 #endif
+    {EXPAND_MAPCLEAR, "mapclear"},
     {EXPAND_MAPPINGS, "mapping"},
     {EXPAND_MENUS, "menu"},
     {EXPAND_MESSAGES, "messages"},
@@ -12083,6 +12097,14 @@ get_messages_arg(expand_T *xp UNUSED, int idx)
 }
 #endif
 
+    char_u *
+get_mapclear_arg(expand_T *xp UNUSED, int idx)
+{
+    if (idx == 0)
+	return (char_u *)"<buffer>";
+    return NULL;
+}
+
 #ifdef FEAT_AUTOCMD
 static int filetype_detect = FALSE;
 static int filetype_plugin = FALSE;

src/ex_getln.c

@@ -4879,6 +4879,7 @@ ExpandFromContext(
 	{
 	    {EXPAND_COMMANDS, get_command_name, FALSE, TRUE},
 	    {EXPAND_BEHAVE, get_behave_arg, TRUE, TRUE},
+	    {EXPAND_MAPCLEAR, get_mapclear_arg, TRUE, TRUE},
 	    {EXPAND_MESSAGES, get_messages_arg, TRUE, TRUE},
 #ifdef FEAT_CMDHIST
 	    {EXPAND_HISTORY, get_history_arg, TRUE, TRUE},

src/proto/ex_docmd.pro

@@ -62,4 +62,5 @@ int put_line(FILE *fd, char *s);
 void dialog_msg(char_u *buff, char *format, char_u *fname);
 char_u *get_behave_arg(expand_T *xp, int idx);
 char_u *get_messages_arg(expand_T *xp, int idx);
+char_u *get_mapclear_arg(expand_T *xp, int idx);
 /* vim: set ft=c : */

src/testdir/test_cmdline.vim

@@ -222,6 +222,11 @@ func Test_getcompletion()
   let l = getcompletion('not', 'messages')
   call assert_equal([], l)
 
+  let l = getcompletion('', 'mapclear')
+  call assert_true(index(l, '<buffer>') >= 0)
+  let l = getcompletion('not', 'mapclear')
+  call assert_equal([], l)
+
   if has('cscope')
     let l = getcompletion('', 'cscope')
     let cmds = ['add', 'find', 'help', 'kill', 'reset', 'show']

src/version.c

@@ -769,6 +769,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    878,
 /**/
     877,
 /**/

src/vim.h

@@ -808,6 +808,7 @@ extern int (*dyn_libintl_putenv)(const char *envstring);
 #define EXPAND_USER_ADDR_TYPE	44
 #define EXPAND_PACKADD		45
 #define EXPAND_MESSAGES		46
+#define EXPAND_MAPCLEAR		47
 
 /* Values for exmode_active (0 is no exmode) */
 #define EXMODE_NORMAL		1