feat(completion): add shown key to complete_info()

Problem: Currently there is no way of getting the list of completion items that are actually shown in the popupmenu. Which means completion providers have no way of knowing if a completion was exhausted.

Solution: Add a `shown` key to `complete_info()` which contains the indices of items that are shown in the popupmenu.

Ref: vim/vim#10007

runtime/doc/news.txt

@@ -385,6 +385,9 @@ The following new APIs and features were added.
 • |vim.fs.root()| finds project root directories from a list of "root
  markers".
 
+• |complete_info()| returns a `shown` item to indicate which items are shown on
+ the |ins-completion-menu|.
+
 ==============================================================================
 CHANGED FEATURES *news-changed*
 

src/nvim/eval.lua

@@ -1367,6 +1367,8 @@ M.funcs = {
  dictionary containing the entries "word",
  "abbr", "menu", "kind", "info" and "user_data".
  See |complete-items|.
+ shown Indices of completion matches that are shown
+ in the |ins-completion-menu|. First index is zero.
  selected Selected item index. First index is zero.
  Index is -1 if no item is selected (showing
  typed text only, or the last completion after

src/nvim/insexpand.c

@@ -2741,8 +2741,9 @@ static void get_complete_info(list_T *what_list, dict_T *retdict)
 #define CI_WHAT_MODE 0x01
 #define CI_WHAT_PUM_VISIBLE 0x02
 #define CI_WHAT_ITEMS 0x04
-#define CI_WHAT_SELECTED 0x08
-#define CI_WHAT_INSERTED 0x10
+#define CI_WHAT_SHOWN 0x08
+#define CI_WHAT_SELECTED 0x10
+#define CI_WHAT_INSERTED 0x20
 #define CI_WHAT_ALL 0xff
  int what_flag;
 
@@ -2761,6 +2762,8 @@ static void get_complete_info(list_T *what_list, dict_T *retdict)
  what_flag |= CI_WHAT_PUM_VISIBLE;
  } else if (strcmp(what, "items") == 0) {
  what_flag |= CI_WHAT_ITEMS;
+ } else if (strcmp(what, "shown") == 0) {
+ what_flag |= CI_WHAT_SHOWN;
  } else if (strcmp(what, "selected") == 0) {
  what_flag |= CI_WHAT_SELECTED;
  } else if (strcmp(what, "inserted") == 0) {
@@ -2778,26 +2781,38 @@ static void get_complete_info(list_T *what_list, dict_T *retdict)
  ret = tv_dict_add_nr(retdict, S_LEN("pum_visible"), pum_visible());
  }
 
- if (ret == OK && (what_flag & CI_WHAT_ITEMS || what_flag & CI_WHAT_SELECTED)) {
- list_T *li = NULL;
+ if (ret == OK
+ && (what_flag & CI_WHAT_ITEMS || what_flag & CI_WHAT_SHOWN || what_flag & CI_WHAT_SELECTED)) {
+ list_T *items = NULL;
+ list_T *shown = NULL;
  int selected_idx = -1;
+ const int lead_len
+ = (what_flag & CI_WHAT_SHOWN) && compl_leader != NULL ? (int)strlen(compl_leader) : 0;
+
  if (what_flag & CI_WHAT_ITEMS) {
- li = tv_list_alloc(kListLenMayKnow);
- ret = tv_dict_add_list(retdict, S_LEN("items"), li);
+ items = tv_list_alloc(kListLenMayKnow);
+ ret = tv_dict_add_list(retdict, S_LEN("items"), items);
+ }
+
+ if (ret == OK && (what_flag & CI_WHAT_SHOWN)) {
+ shown = tv_list_alloc(kListLenUnknown);
+ ret = tv_dict_add_list(retdict, S_LEN("shown"), shown);
  }
- if (ret == OK && what_flag & CI_WHAT_SELECTED) {
+
+ if (ret == OK && (what_flag & CI_WHAT_SELECTED)) {
  if (compl_curr_match != NULL && compl_curr_match->cp_number == -1) {
  ins_compl_update_sequence_numbers();
  }
  }
+
  if (ret == OK && compl_first_match != NULL) {
  int list_idx = 0;
  compl_T *match = compl_first_match;
  do {
  if (!match_at_original_text(match)) {
  if (what_flag & CI_WHAT_ITEMS) {
  dict_T *di = tv_dict_alloc();
- tv_list_append_dict(li, di);
+ tv_list_append_dict(items, di);
  tv_dict_add_str(di, S_LEN("word"), match->cp_str);
  tv_dict_add_str(di, S_LEN("abbr"), match->cp_text[CPT_ABBR]);
  tv_dict_add_str(di, S_LEN("menu"), match->cp_text[CPT_MENU]);
@@ -2810,6 +2825,12 @@ static void get_complete_info(list_T *what_list, dict_T *retdict)
  tv_dict_add_tv(di, S_LEN("user_data"), &match->cp_user_data);
  }
  }
+
+ if ((what_flag & CI_WHAT_SHOWN)
+ && (compl_leader == NULL || ins_compl_equal(match, compl_leader, (size_t)lead_len))) {
+ tv_list_append_number(shown, list_idx);
+ }
+
  if (compl_curr_match != NULL
  && compl_curr_match->cp_number == match->cp_number) {
  selected_idx = list_idx;

test/functional/editor/completion_spec.lua

@@ -1080,6 +1080,34 @@ describe('completion', function()
  ]])
  end)
 
+ describe('complete_info() shown', function()
+ before_each(function()
+ source([[
+ function! TestComplete() abort
+ call complete(1, ['abcd', 'acbd', 'xyz', 'foobar'])
+ return ''
+ endfunction
+
+ set completeopt+=noinsert
+ inoremap <C-x> <c-r>=TestComplete()<cr>
+ ]])
+ end)
+
+ it('works', function()
+ feed('i<C-x>')
+ eq({ shown = { 0, 1, 2, 3 } }, fn.complete_info({ 'shown' }))
+
+ feed('a')
+ eq({ shown = { 0, 1 } }, fn.complete_info({ 'shown' }))
+
+ feed('c')
+ eq({ shown = { 1 } }, fn.complete_info({ 'shown' }))
+
+ feed('x')
+ eq({ shown = {} }, fn.complete_info({ 'shown' }))
+ end)
+ end)
+
  -- oldtest: Test_complete_changed_complete_info()
  it('no crash calling complete_info() in CompleteChanged', function()
  source([[

test/old/testdir/test_ins_complete.vim

@@ -382,7 +382,7 @@ func Test_completefunc_info()
  set completeopt=menuone
  set completefunc=CompleteTest
  call feedkeys("i\<C-X>\<C-U>\<C-R>\<C-R>=string(complete_info())\<CR>\<ESC>", "tx")
- call assert_equal("matched{'pum_visible': 1, 'mode': 'function', 'selected': 0, 'items': [{'word': 'matched', 'menu': '', 'user_data': '', 'info': '', 'kind': '', 'abbr': ''}]}", getline(1))
+ call assert_equal("matched{'shown': [0], 'pum_visible': 1, 'mode': 'function', 'selected': 0, 'items': [{'word': 'matched', 'menu': '', 'user_data': '', 'info': '', 'kind': '', 'abbr': ''}]}", getline(1))
  bwipe!
  set completeopt&
  set completefunc&
@@ -406,7 +406,8 @@ func CompleteInfoTestUserDefinedFn(mvmt, idx, noselect)
  set completefunc=CompleteInfoUserDefinedFn
  call feedkeys("i\<C-X>\<C-U>" . a:mvmt . "\<C-R>\<C-R>=string(complete_info())\<CR>\<ESC>", "tx")
  let completed = a:idx != -1 ? ['foo', 'bar', 'baz', 'qux']->get(a:idx) : ''
- call assert_equal(completed. "{'pum_visible': 1, 'mode': 'function', 'selected': " . a:idx . ", 'items': [" .
+ call assert_equal(completed. "{'shown': [0, 1, 2, 3], 'pum_visible': 1, 'mode': 'function', " .
+ \ "'selected': " . a:idx . ", 'items': [" .
  \ "{'word': 'foo', 'menu': '', 'user_data': '', 'info': '', 'kind': '', 'abbr': ''}, " .
  \ "{'word': 'bar', 'menu': '', 'user_data': '', 'info': '', 'kind': '', 'abbr': ''}, " .
  \ "{'word': 'baz', 'menu': '', 'user_data': '', 'info': '', 'kind': '', 'abbr': ''}, " .

test/old/testdir/test_popup.vim

@@ -1101,6 +1101,7 @@ func Test_popup_complete_info_02()
  \  {'word': 'May', 'menu': 'May', 'user_data': '', 'info': '', 'kind': '', 'abbr': ''}
  \  ],
  \  'selected': 0,
+ \  'shown': [0, 1, 2, 3, 4],
  \ }
 
  let g:compl_what = []
@@ -1109,6 +1110,7 @@ func Test_popup_complete_info_02()
 
  let g:compl_what = ['mode', 'pum_visible', 'selected']
  call remove(d, 'items')
+ call remove(d, 'shown')
  call feedkeys("i\<C-X>\<C-U>\<F5>", 'tx')
  call assert_equal(d, g:compl_info)
 
@@ -1129,6 +1131,7 @@ func Test_popup_complete_info_no_pum()
  \  'pum_visible': 0,
  \  'items': [],
  \  'selected': -1,
+ \  'shown': [],
  \  }
  call assert_equal( d, complete_info() )
  bwipe!