fix(decorations): nvim_buf_set_extmark breaks conceal #19010

Closes #19007

Co-authored-by: bfredl <bjorn.linse@gmail.com>
Co-authored-by: Justin M. Keyes <justinkz@gmail.com>

1 files changed, 15 insertions, 0 deletions

diff --git a/test/functional/ui/decorations_spec.lua b/test/functional/ui/decorations_spec.lua
index cf4845474f..9af5d386db 100644
--- a/test/functional/ui/decorations_spec.lua
+++ b/test/functional/ui/decorations_spec.lua
@@ -483,6 +483,7 @@ describe('extmark decorations', function()
       [23] = {foreground = Screen.colors.Magenta1, background = Screen.colors.LightGrey};
       [24] = {bold = true};
       [25] = {background = Screen.colors.LightRed};
+      [26] = {background=Screen.colors.DarkGrey, foreground=Screen.colors.LightGrey};
     }
 
     ns = meths.create_namespace 'test'
@@ -864,6 +865,20 @@ end]]
     ]]}
     helpers.assert_alive()
   end)
+
+  it('conceal #19007', function()
+    screen:try_resize(50, 5)
+    insert('foo\n')
+    command('let &conceallevel=2')
+    meths.buf_set_extmark(0, ns, 0, 0, {end_col=0, end_row=2, conceal='X'})
+    screen:expect([[
+        {26:X}                                                 |
+        ^                                                  |
+        {1:~                                                 }|
+        {1:~                                                 }|
+                                                          |
+      ]])
+  end)
 end)
 
 describe('decorations: virtual lines', function()