Entities not loaded for relationships on same entity type

I can confirm that this patch corrects the problem stated. I was actually trying to chase down a very similar bug which is the same symptom with the reversed relationship. I attach here an updated View that demonstrates that this patch does not fix the entire issue. I'll try and update the patch to work in both directions. Nice catch and fix @bforchhammer !

First just rerolling against HEAD

Ah looks like my View was bad. Here is a better one..

Ok to make this patch work with reversed entity references I've just added the relationship_id to the `entity_tables` key. Is there a better unique name? Should the aliases be UUID's? Field names?

Oops patch included the .orig. Sorry.

Oops totally got that backwards.

The general idea totally makes sense, we have to take care about relationships when we load all those entities.

+++ b/core/modules/views/src/Plugin/views/query/Sql.php
@@ -1468,30 +1468,40 @@ function loadEntities(&$results) {
-          $ids_by_type[$entity_type][$index] = $result->$id_alias;
+          $ids_by_type[$entity_type][$index][$relationship_id] = $result->$id_alias;

should we maybe rename the variable to reflect the new structure?

Sadly we certainly needs some kind of test coverage so this doesn't break anymore in the future.

Hey thanks for talking a look. That snippet you mention came via @bforchhammer and @webflo. I've made only a minor change so I'm not really clear on what is going on there. What would you suggest as a new variable name?

So the bug is that we are missing fields in Views on an entity when we add an entity reference relationship (or a reverse relationship). So a test would be

* Create a content type (A)
* Create a content type (B) with an entity reference field (C)
* Create content of type A (Aa) with body content
* Create content of type B (Ba) with body content and a reference to Aa

* Create a View of content of type B
* Add a relationship to content referenced by field C
* Access field 'body' on Ba

* Create a View of content of type A
* Add a reverse relationship to content referencing via field C
* Access field 'body' on Aa

Does that sound right? Have I missed any steps?

Perfect!

The existing test coverage also tests _relationship_entity

Committed a4bb2fa and pushed to 8.0.x. Thanks!

Thanks for adding the beta evaluation to the issue summary.

re #29 - fixed :)