Support <Down> and <Up> arrow keys

Close liuchengxu#26

README.md

@@ -133,7 +133,7 @@ The option naming convention for provider is `g:clap_provider_{provider_id}_{opt
 
 ### Movement
 
-- Use <kbd>Ctrl-j</kbd> or <kbd>Ctrl-k</kbd> to navigate the result list up and down.
+- Use <kbd>Ctrl-j</kbd>/<kbd>Down</kbd> or <kbd>Ctrl-k</kbd>/<kbd>Up</kbd> to navigate the result list up and down.
 - Use <kbd>Ctrl-a</kbd> to go to the start of the input.
 - Use <kbd>Ctrl-e</kbd> to go to the end of the input.
 - Use <kbd>Ctrl-c</kbd>, <kbd>Ctrl-[</kbd> or <kbd>Esc</kbd> to exit.

autoload/clap/popup.vim

@@ -299,7 +299,9 @@ function! s:move_manager.bs(_winid) abort
 endfunction
 
 let s:move_manager["\<C-J>"] = { winid -> win_execute(winid, 'call clap#handler#navigate_result("down")') }
+let s:move_manager["\<Down>"] = s:move_manager["\<C-J>"]
 let s:move_manager["\<C-K>"] = { winid -> win_execute(winid, 'call clap#handler#navigate_result("up")') }
+let s:move_manager["\<Up>"] = s:move_manager["\<C-K>"]
 let s:move_manager["\<Tab>"] = { winid -> win_execute(winid, 'call clap#handler#select_toggle()') }
 let s:move_manager["\<CR>"] = { _winid -> clap#handler#sink() }
 let s:move_manager["\<Esc>"] = { _winid -> clap#handler#exit() }

ftplugin/clap_input.vim

@@ -59,6 +59,9 @@ inoremap <silent> <buffer> <Esc> <Esc>:call clap#handler#exit()<CR>
 inoremap <silent> <buffer> <C-j> <C-R>=clap#handler#navigate_result('down')<CR>
 inoremap <silent> <buffer> <C-k> <C-R>=clap#handler#navigate_result('up')<CR>
 
+inoremap <silent> <buffer> <Down> <C-R>=clap#handler#navigate_result('down')<CR>
+inoremap <silent> <buffer> <Up> <C-R>=clap#handler#navigate_result('up')<CR>
+
 inoremap <silent> <buffer> <Tab> <C-R>=clap#handler#select_toggle()<CR>
 
 inoremap <silent> <buffer> <C-t> <Esc>:call <SID>action('ctrl-t')<CR>