vim-patch:9.1.1471: completion: inconsistent ordering with CTRL-P (#34571)

Problem:  completion: inconsistent ordering with CTRL-P
          (zeertzjq)
Solution: reset compl_curr_match when using CTRL-P (Girish Palya)

fixes: vim/vim#17425
closes: vim/vim#17434

5fbe72edda

Co-authored-by: Girish Palya <girishji@gmail.com>

src/nvim/edit.c

@@ -607,7 +607,7 @@ static int insert_execute(VimState *state, int key)
                && (s->c == CAR || s->c == K_KENTER || s->c == NL)))
           && stop_arrow() == OK) {
         ins_compl_delete(false);
-        ins_compl_insert(false, false);
+        ins_compl_insert(false);
       } else if (ascii_iswhite_nl_or_nul(s->c) && ins_compl_preinsert_effect()) {
         // Delete preinserted text when typing special chars
         ins_compl_delete(false);

src/nvim/insexpand.c

@@ -2153,7 +2153,7 @@ static void ins_compl_new_leader(void)
   if (compl_match_array == NULL) {
     compl_enter_selects = false;
   } else if (ins_compl_has_preinsert() && compl_leader.size > 0) {
-    ins_compl_insert(false, true);
+    ins_compl_insert(true);
   }
   // Don't let Enter select when use user function and refresh_always is set
   if (ins_compl_refresh_always()) {
@@ -4522,6 +4522,14 @@ static int ins_compl_get_exp(pos_T *ini)
 
       compl_started = false;
     }
+
+    // For `^P` completion, reset `compl_curr_match` to the head to avoid
+    // mixing matches from different sources.
+    if (!compl_dir_forward()) {
+      while (compl_curr_match->cp_prev) {
+        compl_curr_match = compl_curr_match->cp_prev;
+      }
+    }
   }
   cpt_sources_index = -1;
   compl_started = true;
@@ -4686,10 +4694,9 @@ static void ins_compl_expand_multiple(char *str)
 }
 
 /// Insert the new text being completed.
-/// "in_compl_func" is true when called from complete_check().
 /// "move_cursor" is used when 'completeopt' includes "preinsert" and when true
 /// cursor needs to move back from the inserted text to the compl_leader.
-void ins_compl_insert(bool in_compl_func, bool move_cursor)
+void ins_compl_insert(bool move_cursor)
 {
   int compl_len = get_compl_len();
   bool preinsert = ins_compl_has_preinsert();
@@ -4714,9 +4721,6 @@ void ins_compl_insert(bool in_compl_func, bool move_cursor)
 
   dict_T *dict = ins_compl_dict_alloc(compl_shown_match);
   set_vim_var_dict(VV_COMPLETED_ITEM, dict);
-  if (!in_compl_func) {
-    compl_curr_match = compl_shown_match;
-  }
 }
 
 /// show the file name for the completion match (if any).  Truncate the file
@@ -4885,9 +4889,7 @@ static int find_next_completion_match(bool allow_get_expansion, int todo, bool a
 ///
 /// @param count          Repeat completion this many times; should be at least 1
 /// @param insert_match   Insert the newly selected match
-/// @param in_compl_func  Called from complete_check()
-static int ins_compl_next(bool allow_get_expansion, int count, bool insert_match,
-                          bool in_compl_func)
+static int ins_compl_next(bool allow_get_expansion, int count, bool insert_match)
 {
   int num_matches = -1;
   int todo = count;
@@ -4947,12 +4949,12 @@ static int ins_compl_next(bool allow_get_expansion, int count, bool insert_match
     restore_orig_extmarks();
   } else if (insert_match) {
     if (!compl_get_longest || compl_used_match) {
-      ins_compl_insert(in_compl_func, true);
+      ins_compl_insert(true);
     } else {
       assert(compl_leader.data != NULL);
       ins_compl_insert_bytes(compl_leader.data + get_compl_len(), -1);
     }
-    if (strequal(compl_curr_match->cp_str.data, compl_orig_text.data)) {
+    if (strequal(compl_shown_match->cp_str.data, compl_orig_text.data)) {
       restore_orig_extmarks();
     }
   } else {
@@ -5019,8 +5021,7 @@ void ins_compl_check_keys(int frequency, bool in_compl_func)
     if (vim_is_ctrl_x_key(c) && c != Ctrl_X && c != Ctrl_R) {
       c = safe_vgetc();         // Eat the character
       compl_shows_dir = ins_compl_key2dir(c);
-      ins_compl_next(false, ins_compl_key2count(c),
-                     c != K_UP && c != K_DOWN, in_compl_func);
+      ins_compl_next(false, ins_compl_key2count(c), c != K_UP && c != K_DOWN);
     } else {
       // Need to get the character to have KeyTyped set.  We'll put it
       // back with vungetc() below.  But skip K_IGNORE.
@@ -5040,7 +5041,7 @@ void ins_compl_check_keys(int frequency, bool in_compl_func)
     int todo = compl_pending > 0 ? compl_pending : -compl_pending;
 
     compl_pending = 0;
-    ins_compl_next(false, todo, true, in_compl_func);
+    ins_compl_next(false, todo, true);
   }
 }
 
@@ -5692,7 +5693,7 @@ int ins_complete(int c, bool enable_pum)
   // Find next match (and following matches).
   int save_w_wrow = curwin->w_wrow;
   int save_w_leftcol = curwin->w_leftcol;
-  int n = ins_compl_next(true, ins_compl_key2count(c), insert_match, false);
+  int n = ins_compl_next(true, ins_compl_key2count(c), insert_match);
 
   if (n > 1) {          // all matches have been found
     compl_matches = n;

test/old/testdir/test_ins_complete.vim

@@ -4835,6 +4835,73 @@ func Test_complete_unloaded_buf_refresh_always()
   delfunc TestComplete
 endfunc
 
+" Verify that the order of matches from each source is consistent
+" during both ^N and ^P completions (Issue #17425).
+func Test_complete_with_multiple_function_sources()
+  func F1(findstart, base)
+    if a:findstart
+      return col('.') - 1
+    endif
+    return ['one', 'two', 'three']
+  endfunc
+
+  func F2(findstart, base)
+    if a:findstart
+      return col('.') - 1
+    endif
+    return ['four', 'five', 'six']
+  endfunc
+
+  func F3(findstart, base)
+    if a:findstart
+      return col('.') - 1
+    endif
+    return ['seven', 'eight', 'nine']
+  endfunc
+
+  new
+  setlocal complete=.,FF1,FF2,FF3
+  inoremap <buffer> <F2> <Cmd>let b:matches = complete_info(["matches"]).matches<CR>
+  call setline(1, ['xxx', 'yyy', 'zzz', ''])
+
+  call feedkeys("GS\<C-N>\<F2>\<Esc>0", 'tx!')
+  call assert_equal([
+        \ 'xxx', 'yyy', 'zzz',
+        \ 'one', 'two', 'three',
+        \ 'four', 'five', 'six',
+        \ 'seven', 'eight', 'nine',
+        \ ], b:matches->mapnew('v:val.word'))
+
+  call feedkeys("GS\<C-P>\<F2>\<Esc>0", 'tx!')
+  call assert_equal([
+        \ 'seven', 'eight', 'nine',
+        \ 'four', 'five', 'six',
+        \ 'one', 'two', 'three',
+        \ 'xxx', 'yyy', 'zzz',
+        \ ], b:matches->mapnew('v:val.word'))
+
+  %delete
+
+  call feedkeys("GS\<C-N>\<F2>\<Esc>0", 'tx!')
+  call assert_equal([
+        \ 'one', 'two', 'three',
+        \ 'four', 'five', 'six',
+        \ 'seven', 'eight', 'nine',
+        \ ], b:matches->mapnew('v:val.word'))
+
+  call feedkeys("GS\<C-P>\<F2>\<Esc>0", 'tx!')
+  call assert_equal([
+        \ 'seven', 'eight', 'nine',
+        \ 'four', 'five', 'six',
+        \ 'one', 'two', 'three',
+        \ ], b:matches->mapnew('v:val.word'))
+
+  bwipe!
+  delfunc F1
+  delfunc F2
+  delfunc F3
+endfunc
+
 func Test_complete_fuzzy_omnifunc_backspace()
   let g:do_complete = v:false
   func Omni_test(findstart, base)