fix(lua): wrong script context for option set by func from nvim_exec2 (#32659)

Problem:  Wrong script context for option set by function defined by
          nvim_exec2 in a Lua script.
Solution: Call nlua_set_sctx() after adding SOURCING_LNUM and always set
          sc_lnum for a Lua script.

This is a bug discovered when testing #28486. Not sure if this actually
happens in practice, but it's easy to fix and required for #28486.

1 files changed, 24 insertions, 2 deletions

diff --git a/test/functional/ex_cmds/verbose_spec.lua b/test/functional/ex_cmds/verbose_spec.lua
index 071e9690fa..0187baf4ac 100644
--- a/test/functional/ex_cmds/verbose_spec.lua
+++ b/test/functional/ex_cmds/verbose_spec.lua
@@ -23,7 +23,7 @@ local function last_set_lua_verbose_tests(cmd, v1)
 
     write_file(
       script_file,
-      [[
+      [=[
 vim.api.nvim_set_option_value('hlsearch', false, {})
 vim.bo.expandtab = true
 vim.opt.number = true
@@ -70,8 +70,17 @@ endfunction\
 let &tw = s:return80()\
 ", {})
 
+local set_list = ([[
+  func SetList()
+%s
+    set list
+  endfunc
+  call SetList()
+]]):format(('\n'):rep(1234))
+vim.api.nvim_exec2(set_list, {})
+
 vim.api.nvim_create_autocmd('User', { pattern = 'set_mouse', callback = cb })
-]]
+]=]
     )
     exec(cmd .. ' ' .. script_file)
     exec('doautocmd User set_mouse')
@@ -259,6 +268,19 @@ TestHL2        xxx guibg=Green
       result
     )
   end)
+
+  it('for option set by function in nvim_exec2', function()
+    local result = exec_capture(':verbose set list?')
+    eq(
+      string.format(
+        [[
+  list
+	Last set from %s]],
+        get_last_set_location(54)
+      ),
+      result
+    )
+  end)
 end
 
 describe('lua :verbose with -V1', function()