private Variance calculateArgumentProjectionKindFromSuper(
@NotNull TypeProjection argument,
@NotNull List<TypeProjectionAndVariance> projectionsFromSuper) {
Set<Variance> projectionKindsInSuper = Sets.newLinkedHashSet();
for (TypeProjectionAndVariance projectionAndVariance : projectionsFromSuper) {
projectionKindsInSuper.add(projectionAndVariance.typeProjection.getProjectionKind());
}
Variance defaultProjectionKind = argument.getProjectionKind();
if (projectionKindsInSuper.size() == 0) {
return defaultProjectionKind;
} else if (projectionKindsInSuper.size() == 1) {
Variance projectionKindInSuper = projectionKindsInSuper.iterator().next();
if (defaultProjectionKind == INVARIANT || defaultProjectionKind == projectionKindInSuper) {
return projectionKindInSuper;
} else {
reportError(
"Incompatible projection kinds in type arguments of super methods' return types: "
+ projectionsFromSuper
+ ", defined in current: "
+ argument);
return defaultProjectionKind;
}
} else {
reportError(
"Incompatible projection kinds in type arguments of super methods' return types: "
+ projectionsFromSuper);
return defaultProjectionKind;
}
}
