fix(column): rebuild status column when sign column is invalidated (#22690)

* fix(column): rebuild status column when sign column is invalidated

Problem:    When implementing a custom sign column through
            `'statuscolumn'`, the status column is not properly rebuilt
            when the sign column width changes.
Solution:   Force a rebuild of the status column when the sign column
            width is invalidated.

* test(column): 'statuscolumn' has correct width when (un)placing signs

1 files changed, 36 insertions, 0 deletions

diff --git a/test/functional/ui/statuscolumn_spec.lua b/test/functional/ui/statuscolumn_spec.lua
index d9385ef221..0a253455ad 100644
--- a/test/functional/ui/statuscolumn_spec.lua
+++ b/test/functional/ui/statuscolumn_spec.lua
@@ -557,4 +557,40 @@ describe('statuscolumn', function()
                                                            |
     ]])
   end)
+
+  it("has correct width with custom sign column when (un)placing signs", function()
+    screen:try_resize(screen._width, 6)
+    exec_lua([[
+      vim.cmd.norm('gg')
+      vim.o.signcolumn = 'no'
+      vim.fn.sign_define('sign', { text = 'ss' })
+      _G.StatusCol = function()
+        local s = vim.fn.sign_getplaced(1)[1].signs
+        local sign = ''
+        if #s > 0 then
+          sign = vim.v.lnum == 5 and 'ss' or '  '
+        end
+        return vim.v.lnum .. '%=' .. sign
+      end
+      vim.o.statuscolumn = "%!v:lua.StatusCol()"
+      vim.fn.sign_place(0, '', 'sign', 1, { lnum = 5 })
+    ]])
+    screen:expect([[
+      1   ^aaaaa                                            |
+      2   aaaaa                                            |
+      3   aaaaa                                            |
+      4   aaaaa                                            |
+      5 ssaaaaa                                            |
+                                                           |
+    ]])
+    command('sign unplace 1')
+    screen:expect([[
+      1 ^aaaaa                                              |
+      2 aaaaa                                              |
+      3 aaaaa                                              |
+      4 aaaaa                                              |
+      5 aaaaa                                              |
+                                                           |
+    ]])
+  end)
 end)