field_tags is missing in $entity if field is empty on "node/add" [#1953804]

I have the issue #1923328: Notice: Undefined property: stdClass::$field_tags in linkchecker that I do not understand yet and I need some help about this field issue.

If a new article node is added (via node/add) the field_tags field is completely missing in the $entity. This seems not happen if you edit the node later (node/edit). I get a notice for line $entity->$field['field_name'];, but I think this field_name must always exists in the entity. I cannot find any other example in core that handle or workaround this type of notices.

Code example:

  // Collect the fields from this entity_type and bundle.
  foreach (field_info_instances($entity_type, $bundle_name) as $field_name => $instance) {
    $field = field_info_field($field_name);
    // #1923328: field_name array may be missing in $entity if field is empty.
    $entity_field = $entity->$field['field_name'];

  ...

What's wrong here?

Here is a ling to the full source code: http://drupalcode.org/project/linkchecker.git/blob/refs/heads/7.x-1.x:/l...

Comments

Comment #0.0

hass CreditAttribution: hass commented 27 March 2013 at 00:06

Issue summary:

View changes

Comment #1

yched CreditAttribution: yched commented 5 April 2013 at 20:07

the field_tags field is completely missing in the $entity

Where are we in the code flow ? Which hook, step or function ?

[edit: oops, sorry, there's a link in the OP - a bit buried in function calls though. Can you point to the place in the callstack where those are called ?]

Comment #2

hass CreditAttribution: hass commented 5 April 2013 at 20:30

I'm getting the $node object in hook_node_insert(). Than later _linkchecker_parse_fields('node', $node->type, $node, TRUE)) (http://drupalcode.org/project/linkchecker.git/blob/refs/heads/7.x-1.x:/l...) is called and 9 lines later the code snippet from above is in action.

Does this make things clear?