[Feature request]: API/mapping to manually trigger completions

[subtleseeker]

Issue Prelude

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Issue Details

Is there a way YCM shows suggestions only if I press tab and not as I type. I have searched and tried a bunch of things but can't seem to find it.

Output of vim --version

VIM - Vi IMproved 8.2 (2019 Dec 12, compiled Mar  3 2021 07:02:32)
Included patches: 1-2562
Compiled by nikhil.mundra@nikhil-mundra
Huge version without GUI.  Features included (+) or not (-):
+acl               -farsi             +mouse_sgr         +tag_binary
+arabic            +file_in_path      -mouse_sysmouse    -tag_old_static
+autocmd           +find_in_path      +mouse_urxvt       -tag_any_white
+autochdir         +float             +mouse_xterm       -tcl
-autoservername    +folding           +multi_byte        +termguicolors
-balloon_eval      -footer            +multi_lang        +terminal
+balloon_eval_term +fork()            -mzscheme          +terminfo
-browse            +gettext           +netbeans_intg     +termresponse
++builtin_terms    -hangul_input      +num64             +textobjects
+byte_offset       +iconv             +packages          +textprop
+channel           +insert_expand     +path_extra        +timers
+cindent           +ipv6              +perl              +title
-clientserver      +job               +persistent_undo   -toolbar
-clipboard         +jumplist          +popupwin          +user_commands
+cmdline_compl     +keymap            +postscript        +vartabs
+cmdline_hist      +lambda            +printer           +vertsplit
+cmdline_info      +langmap           +profile           +virtualedit
+comments          +libcall           +python            +visual
+conceal           +linebreak         -python3           +visualextra
+cryptv            +lispindent        +quickfix          +viminfo
+cscope            +listcmds          +reltime           +vreplace
+cursorbind        +localmap          +rightleft         +wildignore
+cursorshape       +lua               +ruby              +wildmenu
+dialog_con        +menu              +scrollbind        +windows
+diff              +mksession         +signs             +writebackup
+digraphs          +modify_fname      +smartindent       -X11
-dnd               +mouse             -sound             -xfontset
-ebcdic            -mouseshape        +spell             -xim
+emacs_tags        +mouse_dec         +startuptime       -xpm
+eval              -mouse_gpm         +statusline        -xsmp
+ex_extra          -mouse_jsbterm     -sun_workshop      -xterm_clipboard
+extra_search      +mouse_netterm     +syntax            -xterm_save
   system vimrc file: "$VIM/vimrc"
     user vimrc file: "$HOME/.vimrc"
 2nd user vimrc file: "~/.vim/vimrc"
      user exrc file: "$HOME/.exrc"
       defaults file: "$VIMRUNTIME/defaults.vim"
  fall-back for $VIM: "/usr/local/share/vim"
Compilation: gcc -std=gnu99 -c -I. -Iproto -DHAVE_CONFIG_H -g -O2 -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=1
Linking: gcc -std=gnu99 -L. -Wl,-z,relro -fstack-protector -rdynamic -Wl,-export-dynamic -Wl,--enable-new-dtags -Wl,-rpath,/usr/lib64/perl5/CORE -L/usr/local/lib -Wl,--as-needed -o vim -lm -ltinfo -ldl -L/usr/lib -llua -Wl,--enable-new-dtags -Wl,-rpath,/usr/lib64/perl5/CORE -fstack-protector -L/usr/lib64/perl5/CORE -lperl -lresolv -lnsl -ldl -lm -lcrypt -lutil -lpthread -lc -L/usr/lib64/python2.7/config -lpython2.7 -lpthread -ldl -lutil -lm -Xlinker -export-dynamic -lruby -lpthread -lrt -ldl -lcrypt -lm -L/usr/lib64

[bstaletic]

Not currently, but you can try the following diff:

diff --git a/autoload/youcompleteme.vim b/autoload/youcompleteme.vim
index cf3f3f41..dfab8c0e 100644
--- a/autoload/youcompleteme.vim
+++ b/autoload/youcompleteme.vim
@@ -855,7 +855,7 @@ function! s:OnTextChangedInsertMode( popup_is_visible )
         \ ( g:ycm_auto_trigger || s:force_semantic ) &&
         \ !s:InsideCommentOrStringAndShouldStop() &&
         \ !s:OnBlankLine()
-    " The call to s:Complete here is necessary, to minimize flicker when we
+    " The call to youcompleteme#Complete here is necessary, to minimize flicker when we
     " close the pum on every keypress. In that case, we try to quickly show it
     " again with whatver the latest completion result is. When using complete(),
     " we don't need to do this, as we only close the pum when there are no
@@ -864,7 +864,7 @@ function! s:OnTextChangedInsertMode( popup_is_visible )
     " keys to filter (that are not a prefix of the completion), then deleting a
     " character. Normally Vim would re-filter based on the new "query", but we
     " don't want that.
-    call s:Complete()
+    call youcompleteme#Complete()
     call s:RequestCompletion()

     call s:UpdateSignatureHelp()
@@ -1030,7 +1030,7 @@ function! s:PollCompletion( ... )
   endif

   let s:completion = py3eval( 'ycm_state.GetCompletionResponse()' )
-  call s:Complete()
+  call youcompleteme#Complete()
 endfunction


@@ -1106,7 +1106,7 @@ function! s:PollSignatureHelp( ... )
   call s:UpdateSignatureHelp()
 endfunction

-function! s:Complete()
+function! youcompleteme#Complete()
   " It's possible for us to be called (by our timer) when we're not _strictly_
   " in insert mode. This can happen when mode is temporarily switched, e.g.
   " due to Ctrl-r or Ctrl-o or a timer or something. If we're not in insert

Then:

1. Set g:ycm_min_num_of_chars_for_completion to 99999999999999999
2. Map <Tab> to call youcompleteme#Complete() in insert mode.

[puremourning]

I’d be happy to add this api. When we stopped using completefunc we sort of regressed this capability.

[subtleseeker]

Yeah, it would be good to have this functionality for those who don't want suggestions all the time.

[bstaletic]

@puremourning s/s:Complete/youcompleteme#Complete/ is simple enough. Do we also want some <Plug> map?

[puremourning]

Yeah plug map would be good.

[bstaletic]

Like I said, my approach didn't work, because it doesn't actually send the completion request. It just checks if a response arrived.

[hinell]

Thumbing up this issue. I don't get why the fact that we don't have to press a shortcut to get completions is listed on main page as an advantage. It's advantage in the sense that it's not mandatory, but we still have to have an ability to set up keybinding for completion activation.

[puremourning]

please can you try PR #4097 ?