fix(column): redraw and update signcols for paired extmark

Problem:  Signcolumn width does not increase when ranged sign does not
          start at sentinel line.
Solution: Handle paired range of added sign when checking signcols.

src/nvim/buffer.c

@@ -4055,7 +4055,7 @@ void buf_signcols_del_check(buf_T *buf, linenr_T line1, linenr_T line2)
 ///
 /// @param buf   buffer to check
 /// @param added sign being added
-void buf_signcols_add_check(buf_T *buf, linenr_T lnum)
+void buf_signcols_add_check(buf_T *buf, linenr_T line1, linenr_T line2)
 {
   if (!buf->b_signcols.valid) {
     return;
@@ -4066,7 +4066,9 @@ void buf_signcols_add_check(buf_T *buf, linenr_T lnum)
     return;
   }
 
-  if (lnum == buf->b_signcols.sentinel) {
+  linenr_T sent = buf->b_signcols.sentinel;
+
+  if (sent >= line1 && sent <= line2) {
     if (buf->b_signcols.size == buf->b_signcols.max) {
       buf->b_signcols.max++;
     }
@@ -4075,12 +4077,11 @@ void buf_signcols_add_check(buf_T *buf, linenr_T lnum)
     return;
   }
 
-  int signcols = decor_signcols(buf, lnum - 1, lnum - 1, SIGN_SHOW_MAX);
+  int signcols = decor_signcols(buf, line1 - 1, line2 - 1, SIGN_SHOW_MAX);
 
   if (signcols > buf->b_signcols.size) {
     buf->b_signcols.size = signcols;
     buf->b_signcols.max = signcols;
-    buf->b_signcols.sentinel = lnum;
     redraw_buf_later(buf, UPD_NOT_VALID);
   }
 }

src/nvim/decoration.c

@@ -169,7 +169,7 @@ DecorSignHighlight decor_sh_from_inline(DecorHighlightInline item)
   return conv;
 }
 
-void buf_put_decor(buf_T *buf, DecorInline decor, int row)
+void buf_put_decor(buf_T *buf, DecorInline decor, int row, int row2)
 {
   if (decor.ext) {
     DecorVirtText *vt = decor.data.ext.vt;
@@ -181,7 +181,7 @@ void buf_put_decor(buf_T *buf, DecorInline decor, int row)
     uint32_t idx = decor.data.ext.sh_idx;
     while (idx != DECOR_ID_INVALID) {
       DecorSignHighlight *sh = &kv_A(decor_items, idx);
-      buf_put_decor_sh(buf, sh, row);
+      buf_put_decor_sh(buf, sh, row, row2);
       idx = sh->next;
     }
   }
@@ -202,14 +202,14 @@ void buf_put_decor_virt(buf_T *buf, DecorVirtText *vt)
 }
 
 static int sign_add_id = 0;
-void buf_put_decor_sh(buf_T *buf, DecorSignHighlight *sh, int row)
+void buf_put_decor_sh(buf_T *buf, DecorSignHighlight *sh, int row, int row2)
 {
   if (sh->flags & kSHIsSign) {
     sh->sign_add_id = sign_add_id++;
     buf->b_signs++;
     if (sh->text.ptr) {
       buf->b_signs_with_text++;
-      buf_signcols_add_check(buf, row + 1);
+      buf_signcols_add_check(buf, row + 1, row2 + 1);
     }
   }
 }
@@ -835,7 +835,7 @@ int decor_signcols(buf_T *buf, int row, int end_row, int max)
     }
 
     if (count > signcols) {
-      if (row != end_row) {
+      if (count > buf->b_signcols.size) {
         buf->b_signcols.sentinel = currow + 1;
       }
       if (count >= max) {

src/nvim/extmark.c

@@ -90,7 +90,7 @@ void extmark_set(buf_T *buf, uint32_t ns_id, uint32_t *idp, int row, colnr_T col
 
 revised:
   if (decor_flags || decor.ext) {
-    buf_put_decor(buf, decor, row);
+    buf_put_decor(buf, decor, row, end_row > -1 ? end_row : row);
     decor_redraw(buf, row, end_row > -1 ? end_row : row, decor);
   }
 
@@ -393,7 +393,8 @@ void extmark_apply_undo(ExtmarkUndoObject undo_info, bool undo)
         MarkTreeIter itr[1] = { 0 };
         MTKey mark = marktree_lookup(curbuf->b_marktree, pos.mark, itr);
         mt_itr_rawkey(itr).flags &= (uint16_t) ~MT_FLAG_INVALID;
-        buf_put_decor(curbuf, mt_decor(mark), mark.pos.row);
+        MTPos end = marktree_get_altpos(curbuf->b_marktree, mark, itr);
+        buf_put_decor(curbuf, mt_decor(mark), mark.pos.row, end.row < 0 ? mark.pos.row : end.row);
       }
       if (pos.old_row >= 0) {
         extmark_setraw(curbuf, pos.mark, pos.old_row, pos.old_col);

test/functional/ui/decorations_spec.lua

@@ -4718,21 +4718,19 @@ l5
       {2:~                                                 }|
                                                         |
     ]]}
-
   end)
 
   it('can add multiple signs (multiple extmarks) 2', function()
     insert(example_test3)
     feed 'gg'
 
-    meths.buf_set_extmark(0, ns, 1, -1, {sign_text='S1'})
+    meths.buf_set_extmark(0, ns, 3, -1, {sign_text='S1'})
-    meths.buf_set_extmark(0, ns, 1, -1, {sign_text='S2'})
+    meths.buf_set_extmark(0, ns, 1, -1, {sign_text='S2', end_row = 3})
-
     screen:expect{grid=[[
       {1:    }^l1                                            |
-      S1S2l2                                            |
+      S2{1:  }l2                                            |
-      {1:    }l3                                            |
+      S2{1:  }l3                                            |
-      {1:    }l4                                            |
+      S1S2l4                                            |
       {1:    }l5                                            |
       {1:    }                                              |
       {2:~                                                 }|
@@ -4740,23 +4738,6 @@ l5
       {2:~                                                 }|
                                                         |
     ]]}
-
-    -- TODO(lewis6991): Support ranged signs
-    -- meths.buf_set_extmark(1, ns, 1, -1, {sign_text='S3', end_row = 2})
-
-    -- screen:expect{grid=[[
-    --   {1:      }^l1                                          |
-    --   S3S2S1l2                                          |
-    --   S3{1:    }l3                                          |
-    --   {1:      }l4                                          |
-    --   {1:      }l5                                          |
-    --   {1:      }                                            |
-    --   {2:~                                                 }|
-    --   {2:~                                                 }|
-    --   {2:~                                                 }|
-    --                                                     |
-    -- ]]}
-
   end)
 
   it('can add multiple signs (multiple extmarks) 3', function()