checker/tests/nullness/generics/Issue329.java

// Test case for Issue 329:
// https://github.com/typetools/checker-framework/issues/329

import org.checkerframework.checker.nullness.qual.Nullable;

abstract class Issue329 {
  interface Flag<T> {}

  abstract <X> void setExtension(X value);

  abstract <T> T getValue(Flag<T> flag);

  void f(Flag<String> flag) {
    String s = getValue(flag);
    setExtension(s);

    setExtension(getValue(flag));
  }
}

abstract class Issue329NN {
  interface Flag<T> {}

  // Explicit bound makes it NonNull
  abstract <X extends Object> void setExtension(X value);

  abstract <T> T getValue(Flag<T> flag);

  void f1(Flag<@Nullable String> flag) {
    String s = getValue(flag);
    // :: error: (type.argument)
    setExtension(s);
  }

  void f2(Flag<@Nullable String> flag) {
    // TODO: false negative. See #979.
    //// :: error: (type.argument)
    setExtension(getValue(flag));
  }
}