Decorators do not merge interfaces

[ooflorent]

Q	A
Bug report?	yes
Feature request?	no
BC Break report?	no
RFC?	no
Version/Branch	master

Given the following schema definition:

InterfaceA:
  type: interface
  config:
    fields:
      a:
        type: String

InterfaceB:
  type: interface
  config:
    fields:
      b:
        type: String

DecoratorA:
  type: object
  decorator: true
  config:
    interfaces:
      - InterfaceA
    fields:
      a:
        type: String

AandB:
  inherits:
    - DecoratorA
  config:
    implements:
      - InterfaceB
    fields:
      b:
        type: String

Problem

AandB does not implement InterfaceA.

Expected behavior

AandB implements InterfaceA and InterfaceB

[akomm]

note: This is a general problem for all configs merged, due to the fact how array_replace_recursive works. It replaces by key and here you have key "0" for both interfaces, so the later replaces. The fix will only focus on this issue here...