Preview won't hold updated Settings states for certain Modules

+++ modules/menu/menu.module	23 Jan 2010 20:10:44 -0000
@@ -632,6 +632,11 @@
+    // set the menu default if it's selected. This wasn't working when previewing.

Comments should be full sentences and thus start with a capital and end with a full stop. The second sentence would have no meaning to a future reader. Remove it?

+++ modules/menu/menu.module	23 Jan 2010 20:10:44 -0000
@@ -632,6 +632,11 @@
+    if ($form_state['values']['menu']['enabled'] == 1) {

I think this should be if ($form_state['values'] and $form_state['values']['menu'] and $form_state['values']['menu']['enabled']) {

Some-most of the testbot errors are because the function is called even when $form_state['values'] is not set (See "Undefined index: 'values'" in the test report). And I don't believe the == 1 comparison is necessary — though I may be mistaken.

+++ modules/menu/menu.module	23 Jan 2010 20:10:44 -0000
@@ -632,6 +632,11 @@
+      $form['menu']['enabled']['#default_value'] = (int) (bool) $form_state['values']['menu']['enabled'];

Similarly I don't think (int) or (bool) are necessary for a checkbox's #default_value. I'm pretty sure that not both are necessary, unless they didn't work without them?

Looks good. Sorry I didn't come back sooner. Another thought;

 $form['menu']['enabled']['#default_value'] = $form_state['values']['menu']['enabled'];

can be simplified to

$form['menu']['enabled']['#default_value'] = 1;

since we know it's value.

Instead of reporting a related issue, I'm going to "hijack" this one...

I had "Preview" required for a custom content type (basic title + body + 1 custom field) and before clicking the Preview button, I had set a URL alias (URL path settings). After saving it, I noticed the alias wasn't created because the alias value wasn't stored when hitting the Preview button.

After checking this issue, I found out that "Menu settings" and "URL path settings" did not keep their values when hitting Preview (unless an error was triggered, eg: when also changing the "Authoring information" to a non-existing user). The "Authoring information" and "Publishing options" settings are always being stored.

This leads me to believe that certain modules (Menu and Path in this case) seem to have the same problem, and it's not just tied to one single module.

(As much as I'd like to hit the "Preview" button on this comment, I'm just going to go for "Save" for now ;))

Edit: I just downloaded the drupal-7.x-dev this morning (don't know if that helps)

I can confirm then same issue as Ben on head.

For the path and menu modules I've changed the code in their respective hook_form_alter() to check if an updated $node is available in $form_state and if so use that to fill in default values.

Joe, please create a new issue node for you patch so that the original issue and patch from comment #8 is not lost. Thanks.

#11: menu-and-path-keep-node-values-with-preview.patch queued for re-testing.