README.md

Do not add __toString() to Entities (consistency issue)

Problem:

PHP (and possibly Doctrine as well) is using __toString() in a lot of internal function that most programmers would expect strict equality comparison. By omitting __toString definition in entity classes, we can avoid a lot of unexpected behavior as the code will fail on Error instead of silently returning a wrong value.

The example illustrates the problem on a simple array_unique call -> see that it's easy to write a test case that passes, it's enough to just flush the entities and therefore retrieve generated IDs. Using pre-generated IDs is of course an option, but it can still surprise the programmer.

Solutions:

• Omit __toString from entities