From 362df0f7938a0e6147ecf886655a0689430d426d Mon Sep 17 00:00:00 2001
From: Ibby <33922797+SleepySwords@users.noreply.github.com>
Date: Sat, 26 Aug 2023 21:39:05 +1000
Subject: [PATCH] fix(extmarks): wrong display when changing text with
 virt_lines (#24879)

---
 src/nvim/change.c                       |  7 ++-
 test/functional/ui/decorations_spec.lua | 57 +++++++++++++++++++++++++
 2 files changed, 63 insertions(+), 1 deletion(-)

diff --git a/src/nvim/change.c b/src/nvim/change.c
index 067b48faee..084a8a1897 100644
--- a/src/nvim/change.c
+++ b/src/nvim/change.c
@@ -319,7 +319,12 @@ static void changed_common(buf_T *buf, linenr_T lnum, colnr_T col, linenr_T lnum
           if (wp->w_lines[i].wl_lnum >= lnum) {
             // Do not change wl_lnum at index zero, it is used to
             // compare with w_topline.  Invalidate it instead.
-            if (wp->w_lines[i].wl_lnum < lnume || i == 0) {
+            // If the buffer has virt_lines, invalidate the line
+            // after the changed lines as the virt_lines for a
+            // changed line may become invalid.
+            if (i == 0 || wp->w_lines[i].wl_lnum < lnume
+                || (wp->w_lines[i].wl_lnum == lnume
+                    && wp->w_buffer->b_virt_line_blocks > 0)) {
               // line included in change
               wp->w_lines[i].wl_valid = false;
             } else if (xtra != 0) {
diff --git a/test/functional/ui/decorations_spec.lua b/test/functional/ui/decorations_spec.lua
index 0a3a2e4e29..36d6fea1de 100644
--- a/test/functional/ui/decorations_spec.lua
+++ b/test/functional/ui/decorations_spec.lua
@@ -3784,6 +3784,63 @@ if (h->n_buckets < new_n_buckets) { // expand
     ]]}
   end)
 
+  it('works when using dd or yyp #23915 #23916', function()
+    insert([[
+      line1
+      line2
+      line3
+      line4
+      line5]])
+    meths.buf_set_extmark(0, ns, 0, 0, {virt_lines={{{"foo"}}, {{"bar"}}, {{"baz"}}}})
+    screen:expect{grid=[[
+      line1                                             |
+      foo                                               |
+      bar                                               |
+      baz                                               |
+      line2                                             |
+      line3                                             |
+      line4                                             |
+      line^5                                             |
+      {1:~                                                 }|
+      {1:~                                                 }|
+      {1:~                                                 }|
+                                                        |
+    ]]}
+
+    feed('gg')
+    feed('dd')
+    screen:expect{grid=[[
+      ^line2                                             |
+      foo                                               |
+      bar                                               |
+      baz                                               |
+      line3                                             |
+      line4                                             |
+      line5                                             |
+      {1:~                                                 }|
+      {1:~                                                 }|
+      {1:~                                                 }|
+      {1:~                                                 }|
+                                                        |
+    ]]}
+
+    feed('yyp')
+    screen:expect{grid=[[
+      line2                                             |
+      foo                                               |
+      bar                                               |
+      baz                                               |
+      ^line2                                             |
+      line3                                             |
+      line4                                             |
+      line5                                             |
+      {1:~                                                 }|
+      {1:~                                                 }|
+      {1:~                                                 }|
+                                                        |
+    ]]}
+  end)
+
 end)
 
 describe('decorations: signs', function()