Conflict with the Diff module [#1910718]

The Diff modules comes with an 'inline differences' block that highlights the differences between the current node and a selected previous revision. The module classifies differences as 'Added', 'Changed' or 'Deleted' and highlights appropriately using a CSS class.

On my site ( which uses Empty Fields ) the Diff module incorrectly identifies added field content as changed ( and also correctly identifies changed field content as changed ). When I turn off the Empty Fields module and refresh the page the Diff module works fine again and added field content is marked as such.

A bit obscure but any ideas ?

Thanks

Comments

Comment #1

El Bandito CreditAttribution: El Bandito commented 22 March 2013 at 11:14

Category:

bug

» support

I've done a bit more investigation of this issue. Perhaps the word 'conflict' was a bit strong - the modules really just don't work together.

The Diff module builds 2 html strings representing the 'full' view mode of 2 versions ( version id ) of a node and then compares them. In pseudocode somthing like :

$old_node = node_load($nid, $old_vid);
node_build_content($old_node);  // defaults to 'full' view mode
$old_node_rendered = drupal_render($old_node->content);

$new_node = node_load($nid, $new_vid);
node_build_content($new_node);
$new_node_rendered = drupal_render($new_node->content);

$diff = compare($old_node_rendered, $new_node_rendered);

The empty fields module hooks into the field preparation process via hook_field_attach_view_alter() and injects the empty text where the field is approrpiately configured. The empty text therefore messes with diff's comparison.

Is there a way to avoid this ? Happy to hack either module given a good suggestion.

Changing from bug >> support request.

Thanks