Merge #28522 handle ui_attach side effects

src/nvim/ui.c

@@ -194,15 +194,6 @@ void ui_refresh(void)
     abort();
   }
 
-  if (!ui_active()) {
-    return;
-  }
-
-  if (updating_screen) {
-    ui_schedule_refresh();
-    return;
-  }
-
   int width = INT_MAX;
   int height = INT_MAX;
   bool ext_widgets[kUIExtCount];
@@ -227,18 +218,29 @@ void ui_refresh(void)
     if (i < kUIGlobalCount) {
       ext_widgets[i] |= ui_cb_ext[i];
     }
-    // Set 'cmdheight' to zero when ext_messages becomes active.
+    // Set 'cmdheight' to zero when ext_messages becomes active for all tabpages.
     if (i == kUIMessages && !ui_ext[i] && ext_widgets[i]) {
       set_option_value(kOptCmdheight, NUMBER_OPTVAL(0), 0);
       command_height();
+      FOR_ALL_TABS(tp) {
+        tp->tp_ch_used = 0;
+      }
     }
     ui_ext[i] = ext_widgets[i];
     if (i < kUIGlobalCount) {
-      ui_call_option_set(cstr_as_string(ui_ext_names[i]),
+      ui_call_option_set(cstr_as_string(ui_ext_names[i]), BOOLEAN_OBJ(ext_widgets[i]));
-                         BOOLEAN_OBJ(ext_widgets[i]));
     }
   }
 
+  if (!ui_active()) {
+    return;
+  }
+
+  if (updating_screen) {
+    ui_schedule_refresh();
+    return;
+  }
+
   ui_default_colors_set();
 
   int save_p_lz = p_lz;

test/functional/lua/ui_event_spec.lua

@@ -155,6 +155,21 @@ describe('vim.ui_attach', function()
       },
     }, actual, vim.inspect(actual))
   end)
+
+  it('ui_refresh() works without remote UI', function()
+    screen:detach()
+    exec_lua('vim.ui_attach(ns, { ext_messages = true }, on_event)')
+    n.api.nvim_set_option_value('cmdheight', 1, {})
+    screen:attach()
+    eq(1, n.api.nvim_get_option_value('cmdheight', {}))
+  end)
+
+  it("ui_refresh() sets 'cmdheight' for all open tabpages with ext_messages", function()
+    exec_lua('vim.cmd.tabnew()')
+    exec_lua('vim.ui_attach(ns, { ext_messages = true }, on_event)')
+    exec_lua('vim.cmd.tabnext()')
+    eq(0, n.api.nvim_get_option_value('cmdheight', {}))
+  end)
 end)
 
 describe('vim.ui_attach', function()