patch 9.1.0010: Keymap completion is not available

Problem:  Keymap completion is not available
Solution: Add keymap completion (Doug Kearns)

Add keymap completion to the 'keymap' option, user commands and builtin
completion functions.

closes: #13692

Signed-off-by: Doug Kearns <dougkearns@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/testdir/test_options.vim b/src/testdir/test_options.vim
index 8c336ab..37dc201 100644
--- a/src/testdir/test_options.vim
+++ b/src/testdir/test_options.vim
@@ -435,6 +435,14 @@
   call assert_equal('"set syntax=sshdconfig', @:)
   call feedkeys(":set syntax=a\<C-A>\<C-B>\"\<CR>", 'xt')
   call assert_equal('"set syntax=' .. getcompletion('a*', 'syntax')->join(), @:)
+
+  if has('keymap')
+    " Expand values for 'keymap'
+    call feedkeys(":set keymap=acc\<Tab>\<C-B>\"\<CR>", 'xt')
+    call assert_equal('"set keymap=accents', @:)
+    call feedkeys(":set keymap=a\<C-A>\<C-B>\"\<CR>", 'xt')
+    call assert_equal('"set keymap=' .. getcompletion('a*', 'keymap')->join(), @:)
+  endif
 endfunc
 
 " Test handling of expanding individual string option values