Declaration order dependency between interface and inherited attribute

JastAdd2 2.1.13-83-g418a5b4

I was supervising two students this autumn in a compiler course project. The students were implementing an ExtendJ extension and they had problems building ExtendJ using JastAddGradle. After some debugging and head-scratching I found out that there is still an order dependency in JastAdd.

I tracked down what was causing the build error and made a minimal test case exposing a declaration order dependency in JastAdd:

// Test declaration order dependency for interface / inherited equation.
// grammar = {A ::= B; B;}
// .result=COMPILE_PASS
aspect Test {
  B implements I;

  inh A I.a();

  interface I {
  }

  eq A.getChild().a() = this;
}

This test case generates the following output from JastAdd2:

    [junit] JastAdd code generation failed when expected to pass:
    [junit] Error at tests/aspect/order_01p/Test.jrag:12: missing declaration for inherited attribute a()

If the interface declaration is moved up before the inherited attribute declaration then JastAdd can generate code, without the above error message.

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