Jira issue originally created by user jurgenf:
The schema validator checks if the target entity exists and if the target entity is transient. It does so with the following comparison:
if (!class_exists($assoc['targetEntity']) ](| $cmf->isTransient($assoc['targetEntity')))
If I understand this comparison correctly it should evaluate to true if $cmf->isTransient is NOT true because the entity is unknown to the driver in this case. If both the class exists and is a registered entity (is transient) then the association is valid.
Comment created by @ocramius:
[~jurgenf] the entity may be transient within a single driver, but not necessarily in the entire class metadata factory
Comment created by jurgenf:
The problem was in a custom metadata driver that returned the wrong transient state.
Issue was closed with resolution "Invalid"