vim-patch:9.2.1004: a completion function cannot tell why it was called (#41500)

Problem:  A function used through 'omnifunc' or 'complete' is called the
          same way whether 'autocomplete' started the completion or a
          key asked for one, so it cannot answer differently.
Solution: Report which of the two it is in complete_info() as "auto". It
          is returned only when asked for in {what}, so what
          complete_info() says by itself does not change
          (Hirohito Higashi).

closes: vim/vim#21143

1f56c351de

Co-authored-by: Hirohito Higashi <h.east.727@gmail.com>

runtime/doc/vimfn.txt

@@ -1316,6 +1316,12 @@ complete_info([{what}])                                        *complete_info()*
 		Returns a |Dictionary| with information about Insert mode
 		completion.  See |ins-completion|.
 		The items are:
+		   auto		|TRUE| when Vim started this completion by
+				itself, which is what 'autocomplete' does,
+				and |FALSE| when a key asked for it, such as
+				|i_CTRL-X_CTRL-O|.  A |complete-functions|
+				function can read this to tell the two apart.
+				Returned only when asked for in {what}.
 		   completed	Return a dictionary containing the entries of
 				the currently selected index item.
 		   items	List of all completion candidates.  Each item

runtime/lua/vim/_meta/vimfn.gen.lua

@@ -1135,6 +1135,12 @@ function vim.fn.complete_check() end
 --- Returns a |Dictionary| with information about Insert mode
 --- completion.  See |ins-completion|.
 --- The items are:
+---    auto    |TRUE| when Vim started this completion by
+---     itself, which is what 'autocomplete' does,
+---     and |FALSE| when a key asked for it, such as
+---     |i_CTRL-X_CTRL-O|.  A |complete-functions|
+---     function can read this to tell the two apart.
+---     Returned only when asked for in {what}.
 ---    completed  Return a dictionary containing the entries of
 ---     the currently selected index item.
 ---    items  List of all completion candidates.  Each item

src/nvim/eval.lua

@@ -1489,6 +1489,12 @@ M.funcs = {
       Returns a |Dictionary| with information about Insert mode
       completion.  See |ins-completion|.
       The items are:
+         auto		|TRUE| when Vim started this completion by
+      		itself, which is what 'autocomplete' does,
+      		and |FALSE| when a key asked for it, such as
+      		|i_CTRL-X_CTRL-O|.  A |complete-functions|
+      		function can read this to tell the two apart.
+      		Returned only when asked for in {what}.
          completed	Return a dictionary containing the entries of
       		the currently selected index item.
          items	List of all completion candidates.  Each item

src/nvim/insert.c

@@ -134,6 +134,7 @@ static kvec_t(char) replace_stack = KV_INITIAL_VALUE;
     update_screen();  /* Show char deletion immediately */ \
     ui_flush(); \
     ins_compl_enable_autocomplete(); \
+    ins_compl_arm_autostart(); \
     if (!ins_compl_arm_autocomplete_delay()) { \
       insert_do_complete(s); \
       break; \
@@ -522,6 +523,7 @@ static int insert_check(VimState *state)
       s->c = char_before_cursor();
       if (vim_isprintc(s->c)) {
         ins_compl_enable_autocomplete();
+        ins_compl_arm_autostart();
         ins_compl_init_get_longest();
         // Defer until the delay expires (K_COMPLETE_DELAY), or
         // trigger now when no delay is in effect.
@@ -563,6 +565,7 @@ static int insert_execute(VimState *state, int key)
   if (key != K_EVENT && key != K_COMPLETE_DELAY) {
     // Don't want delayed autocompletion from the previous key either.
     ins_compl_clear_autocomplete_delay();
+    ins_compl_disarm_autostart();
   }
 
   // Special handling of keys while the popup menu is visible or wanted
@@ -1001,6 +1004,7 @@ static int insert_handle_key(InsertState *s)
     // The completion may have been cleared while waiting, so re-enable
     // autocomplete to match a zero delay.
     ins_compl_enable_autocomplete();
+    ins_compl_arm_autostart();
     insert_do_complete(s);
     break;
 

src/nvim/insexpand.c

@@ -329,6 +329,8 @@ static buf_T *compl_curr_buf = NULL;  ///< buf where completion is active
 // longer fixed timeout is used (COMPL_FUNC_TIMEOUT_MS or
 // COMPL_FUNC_TIMEOUT_NON_KW_MS). - girish
 static bool compl_autocomplete = false;        ///< whether autocompletion is active
+static bool compl_autostarted = false;         ///< Vim started this completion
+static bool compl_autostart_pending = false;   ///< the trigger armed one
 static bool compl_autocomplete_pending = false;
 static uint64_t compl_autocomplete_start_tv;   ///< when the delay was armed
 static uint64_t compl_timeout_ms = COMPL_INITIAL_TIMEOUT_MS;
@@ -2287,6 +2289,7 @@ void ins_compl_clear(void)
   cpt_sources_clear();
   compl_autocomplete = false;
   compl_from_nonkeyword = false;
+  compl_autostarted = false;
   compl_num_bests = 0;
   // clear v:completed_item
   set_vim_var_dict(VV_COMPLETED_ITEM, tv_dict_alloc_lock(VAR_FIXED));
@@ -2586,6 +2589,7 @@ static void ins_compl_restart(void)
   cpt_sources_clear();
   compl_autocomplete = false;
   compl_from_nonkeyword = false;
+  compl_autostarted = false;
   compl_num_bests = 0;
 }
 
@@ -2892,6 +2896,7 @@ static bool ins_compl_stop(const int c, const int prev_mode, bool retval)
   }
   compl_autocomplete = false;
   compl_from_nonkeyword = false;
+  compl_autostarted = false;
   compl_num_bests = 0;
   compl_ins_end_col = 0;
 
@@ -3696,11 +3701,12 @@ static void get_complete_info(list_T *what_list, dict_T *retdict)
 #define CI_WHAT_COMPLETED           0x10
 #define CI_WHAT_MATCHES             0x20
 #define CI_WHAT_PREINSERTED_TEXT    0x40
+#define CI_WHAT_AUTO                0x80
 #define CI_WHAT_ALL                 0xff
   int what_flag;
 
   if (what_list == NULL) {
-    what_flag = CI_WHAT_ALL & ~(CI_WHAT_MATCHES|CI_WHAT_COMPLETED);
+    what_flag = CI_WHAT_ALL & ~(CI_WHAT_MATCHES|CI_WHAT_COMPLETED|CI_WHAT_AUTO);
   } else {
     what_flag = 0;
     for (listitem_T *item = tv_list_first(what_list)
@@ -3722,6 +3728,8 @@ static void get_complete_info(list_T *what_list, dict_T *retdict)
         what_flag |= CI_WHAT_PREINSERTED_TEXT;
       } else if (strcmp(what, "matches") == 0) {
         what_flag |= CI_WHAT_MATCHES;
+      } else if (strcmp(what, "auto") == 0) {
+        what_flag |= CI_WHAT_AUTO;
       }
     }
   }
@@ -3736,6 +3744,10 @@ 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_AUTO)) {
+    ret = tv_dict_add_nr(retdict, S_LEN("auto"), compl_autostarted);
+  }
+
   if (ret == OK && (what_flag & CI_WHAT_PREINSERTED_TEXT)) {
     char *line = get_cursor_line_ptr();
     int len = compl_ins_end_col - curwin->w_cursor.col;
@@ -6317,6 +6329,9 @@ int ins_complete(int c, bool enable_pum)
   int insert_match = ins_compl_use_match(c);
 
   if (!compl_started) {
+    // Only what the automatic trigger armed counts as started by Vim.
+    compl_autostarted = compl_autostart_pending;
+    compl_autostart_pending = false;
     if (ins_compl_start() == FAIL) {
       return FAIL;
     }
@@ -6401,6 +6416,19 @@ void ins_compl_enable_autocomplete(void)
   compl_get_longest = false;
 }
 
+/// Remember that Vim is about to start a completion by itself, rather than
+/// because a key was typed to ask for one.
+void ins_compl_arm_autostart(void)
+{
+  compl_autostart_pending = true;
+}
+
+/// Forget what the automatic trigger armed, another key was typed since.
+void ins_compl_disarm_autostart(void)
+{
+  compl_autostart_pending = false;
+}
+
 /// Arm the 'autocompletedelay' timer when the delay is in effect.
 /// Return true when the popup should be deferred, false to trigger it now.
 bool ins_compl_arm_autocomplete_delay(void)

test/old/testdir/test_ins_complete.vim

@@ -6851,6 +6851,45 @@ func Test_complete_info_hlgroup()
   bwipe!
 endfunc
 
+" Test that complete_info() tells a completion Vim started by itself from one
+" that a key asked for.
+func Test_complete_info_auto()
+  call Ntest_override("char_avail", 1)
+  new
+  func! AutoOmni(findstart, base)
+    if a:findstart
+      call add(g:auto, complete_info(['auto']).auto)
+      return col('.') - 1
+    endif
+    return ['alpha', 'alphabet']
+  endfunc
+  setlocal omnifunc=AutoOmni
+  setlocal complete=o
+  setlocal completeopt=menuone
+  call setline(1, '    al')
+
+  " 'autocomplete' starts it, nothing was asked for.
+  setlocal autocomplete
+  let g:auto = []
+  call feedkeys("A\<Esc>", 'tx')
+  call assert_equal([1], g:auto)
+
+  " The second call is the one CTRL-X CTRL-O asked for.
+  let g:auto = []
+  call feedkeys("A\<C-X>\<C-O>\<Esc>", 'tx')
+  call assert_equal([1, 0], g:auto)
+
+  setlocal noautocomplete
+  let g:auto = []
+  call feedkeys("A\<C-X>\<C-O>\<Esc>", 'tx')
+  call assert_equal([0], g:auto)
+
+  call Ntest_override("ALL", 0)
+  unlet g:auto
+  delfunc AutoOmni
+  bwipe!
+endfunc
+
 func Test_complete_fuzzy_resort()
   new
   set completeopt=menu,menuone,noselect,fuzzy