patch 9.0.0081: command line completion of user command may have duplicates

Problem:    Command line completion of user command may have duplicates.
            (Dani Dickstein)
Solution:   Skip global user command if an identical buffer-local one is
            defined. (closes #10797)
diff --git a/src/testdir/test_cmdline.vim b/src/testdir/test_cmdline.vim
index a69774e..1994a8c 100644
--- a/src/testdir/test_cmdline.vim
+++ b/src/testdir/test_cmdline.vim
@@ -842,6 +842,16 @@
   delcommand Foo
 endfunc
 
+func Test_complete_user_cmd()
+  command FooBar echo 'global'
+  command -buffer FooBar echo 'local'
+  call feedkeys(":Foo\<C-A>\<Home>\"\<CR>", 'tx')
+  call assert_equal('"FooBar', @:)
+
+  delcommand -buffer FooBar
+  delcommand FooBar
+endfunc
+
 func s:ScriptLocalFunction()
   echo 'yes'
 endfunc
diff --git a/src/usercmd.c b/src/usercmd.c
index 1d9c86f..7113511 100644
--- a/src/usercmd.c
+++ b/src/usercmd.c
@@ -363,9 +363,19 @@
 
     if (idx < buf->b_ucmds.ga_len)
 	return USER_CMD_GA(&buf->b_ucmds, idx)->uc_name;
+
     idx -= buf->b_ucmds.ga_len;
     if (idx < ucmds.ga_len)
-	return USER_CMD(idx)->uc_name;
+    {
+	int	i;
+	char_u  *name = USER_CMD(idx)->uc_name;
+
+	for (i = 0; i < buf->b_ucmds.ga_len; ++i)
+	    if (STRCMP(name, USER_CMD_GA(&buf->b_ucmds, i)->uc_name) == 0)
+		// global command is overruled by buffer-local one
+		return (char_u *)"";
+	return name;
+    }
     return NULL;
 }
 
diff --git a/src/version.c b/src/version.c
index 50bf7c4..ad0c1a9 100644
--- a/src/version.c
+++ b/src/version.c
@@ -736,6 +736,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    81,
+/**/
     80,
 /**/
     79,