feat(extmarks,ts,spell): full support for spelling

- Added 'spell' option to extmarks:

  Extmarks with this set will have the region spellchecked.

- Added 'noplainbuffer' option to 'spelloptions':

  This is used to tell Neovim not to spellcheck the buffer. The old
  behaviour was to spell check the whole buffer unless :syntax was set.

- Added spelling support to the treesitter highlighter:

  @spell captures in highlights.scm are used to define regions which
  should be spell checked.

- Added support for navigating spell errors for extmarks:

  Works for both ephemeral and static extmarks

- Added '_on_spell_nav' callback for decoration providers:

  Since ephemeral callbacks are only drawn for the visible screen,
  providers must implement this callback to instruct Neovim which
  regions in the buffer need can be spell checked.

  The callback takes a start position and an end position.

  Note: this callback is subject to change hence the _ prefix.

- Added spell captures for built-in support languages

Co-authored-by: Lewis Russell <lewis6991@gmail.com>
Co-authored-by: Björn Linse <bjorn.linse@gmail.com>

1 files changed, 11 insertions, 1 deletions

diff --git a/src/nvim/decoration.c b/src/nvim/decoration.c
index 8955048f45..778f9293fb 100644
--- a/src/nvim/decoration.c
+++ b/src/nvim/decoration.c
@@ -69,7 +69,7 @@ void bufhl_add_hl_pos_offset(buf_T *buf, int src_id, int hl_id, lpos_T pos_start
 void decor_redraw(buf_T *buf, int row1, int row2, Decoration *decor)
 {
   if (row2 >= row1) {
-    if (!decor || decor->hl_id || decor_has_sign(decor) || decor->conceal) {
+    if (!decor || decor->hl_id || decor_has_sign(decor) || decor->conceal || decor->spell) {
       redraw_buf_range_later(buf, row1 + 1, row2 + 1);
     }
   }
@@ -116,6 +116,11 @@ void decor_free(Decoration *decor)
   }
 }
 
+void decor_state_free(DecorState *state)
+{
+  xfree(state->active.items);
+}
+
 void clear_virttext(VirtText *text)
 {
   for (size_t i = 0; i < kv_size(*text); i++) {
@@ -306,6 +311,7 @@ next_mark:
   bool conceal = 0;
   int conceal_char = 0;
   int conceal_attr = 0;
+  bool spell = false;
 
   for (size_t i = 0; i < kv_size(state->active); i++) {
     DecorRange item = kv_A(state->active, i);
@@ -339,6 +345,9 @@ next_mark:
         conceal_attr = item.attr_id;
       }
     }
+    if (active && item.decor.spell) {
+      spell = true;
+    }
     if ((item.start_row == state->row && item.start_col <= col)
         && decor_virt_pos(item.decor)
         && item.decor.virt_text_pos == kVTOverlay && item.win_col == -1) {
@@ -355,6 +364,7 @@ next_mark:
   state->conceal = conceal;
   state->conceal_char = conceal_char;
   state->conceal_attr = conceal_attr;
+  state->spell = spell;
   return attr;
 }