framework/tests/nontopdefault/NTDTest.java

import org.checkerframework.framework.testchecker.nontopdefault.qual.NTDMiddle;
import org.checkerframework.framework.testchecker.nontopdefault.qual.NTDTop;

// Testcase for Issue 948:
// https://github.com/typetools/checker-framework/issues/948
// @skip-test

// Problem: @DefaultFor TypeUseLocation.RECEIVER is not applied to inner class constructor
// receivers. The inner class constructor receivers currently take on the default qualifier of
// the hierarchy. All other methods take on the default qualifier set by TypeUseLocation.RECEIVER.

// DefaultQualifierInHierarchy is @NTDMiddle
// DefaultFor receivers is @NTDTop

public class NTDConstructorReceiverTest {

  // default method receiver is @NTDTop
  void DefaultMethodReceiver() {

    // this line produces a methodref.receiver.bound error, but it shouldn't if the
    // receiver for inner class constructors are properly applied
    Demand<InnerDefaultReceiver> constructorReference = InnerDefaultReceiver::new;

    // this line does not as the receiver is explicitly declared to be @NTDTop
    Demand<InnerExplicitReceiver> constructorReference2 = InnerExplicitReceiver::new;
  }

  class InnerDefaultReceiver {
    // takes on the default receiver for inner class constructor methods
    InnerDefaultReceiver(NTDConstructorReceiverTest NTDConstructorReceiverTest.this) {
      // The type of NTDConstructorReceiverTest.this should be @NTDTop.
      // :: error: (assignment)
      @NTDMiddle NTDConstructorReceiverTest that = NTDConstructorReceiverTest.this;
      // :: error: (assignment)
      @NTDMiddle NTDConstructorReceiverTest.@NTDTop InnerDefaultReceiver thatInner = this;
    }

    void method() {
      // The TypeUseLocation.RECEIVER only applies to the outermost type, so
      // NTDConstructorReceiverTest.this is given the
      @NTDMiddle NTDConstructorReceiverTest that = NTDConstructorReceiverTest.this;
      // :: error: (assignment)
      @NTDMiddle InnerDefaultReceiver thatInner = this;
    }

    void explicit(@NTDTop NTDConstructorReceiverTest.@NTDTop InnerDefaultReceiver this) {
      // :: error: (assignment)
      @NTDMiddle NTDConstructorReceiverTest that = NTDConstructorReceiverTest.this;
      // :: error: (assignment)
      @NTDMiddle NTDConstructorReceiverTest.@NTDTop InnerDefaultReceiver thatInner = this;
    }
  }

  class InnerExplicitReceiver {
    // explicitly set the receiver to be @NTDTop
    InnerExplicitReceiver(@NTDTop NTDConstructorReceiverTest NTDConstructorReceiverTest.this) {
      // :: error: (assignment)
      @NTDMiddle NTDConstructorReceiverTest that = NTDConstructorReceiverTest.this;
    }

    InnerExplicitReceiver(
        @NTDMiddle NTDConstructorReceiverTest NTDConstructorReceiverTest.this, int i) {
      @NTDMiddle NTDConstructorReceiverTest that = NTDConstructorReceiverTest.this;
    }
  }
}

interface Demand<R> {
  R supply();
}