private List<TypeProjection> substituteTypeArguments( List<TypeParameterDescriptor> typeParameters, List<TypeProjection> typeArguments, int recursionDepth) throws SubstitutionException { List<TypeProjection> substitutedArguments = new ArrayList<TypeProjection>(typeParameters.size()); for (int i = 0; i < typeParameters.size(); i++) { TypeParameterDescriptor typeParameter = typeParameters.get(i); TypeProjection typeArgument = typeArguments.get(i); TypeProjection substitutedTypeArgument = unsafeSubstitute(typeArgument, recursionDepth + 1); switch (conflictType( typeParameter.getVariance(), substitutedTypeArgument.getProjectionKind())) { case NO_CONFLICT: // if the corresponding type parameter is already co/contra-variant, there's not need for // an explicit projection if (typeParameter.getVariance() != Variance.INVARIANT && !substitutedTypeArgument.isStarProjection()) { substitutedTypeArgument = new TypeProjectionImpl(Variance.INVARIANT, substitutedTypeArgument.getType()); } break; case OUT_IN_IN_POSITION: case IN_IN_OUT_POSITION: substitutedTypeArgument = TypeUtils.makeStarProjection(typeParameter); break; } substitutedArguments.add(substitutedTypeArgument); } return substitutedArguments; }
public static boolean dependsOnTypeConstructors( @NotNull KotlinType type, @NotNull Collection<TypeConstructor> typeParameterConstructors) { if (typeParameterConstructors.contains(type.getConstructor())) return true; for (TypeProjection typeProjection : type.getArguments()) { if (!typeProjection.isStarProjection() && dependsOnTypeConstructors(typeProjection.getType(), typeParameterConstructors)) { return true; } } return false; }
public static boolean contains( @Nullable KotlinType type, @NotNull Function1<KotlinType, Boolean> isSpecialType) { if (type == null) return false; if (isSpecialType.invoke(type)) return true; Flexibility flexibility = type.getCapability(Flexibility.class); if (flexibility != null && (contains(flexibility.getLowerBound(), isSpecialType) || contains(flexibility.getUpperBound(), isSpecialType))) { return true; } for (TypeProjection projection : type.getArguments()) { if (!projection.isStarProjection() && contains(projection.getType(), isSpecialType)) return true; } return false; }
@NotNull private TypeProjection unsafeSubstitute( @NotNull TypeProjection originalProjection, int recursionDepth) throws SubstitutionException { assertRecursionDepth(recursionDepth, originalProjection, substitution); if (originalProjection.isStarProjection()) return originalProjection; // The type is within the substitution range, i.e. T or T? JetType type = originalProjection.getType(); TypeProjection replacement = substitution.get(type); Variance originalProjectionKind = originalProjection.getProjectionKind(); if (replacement == null && FlexibleTypesKt.isFlexible(type) && !TypeCapabilitiesKt.isCustomTypeVariable(type)) { Flexibility flexibility = FlexibleTypesKt.flexibility(type); TypeProjection substitutedLower = unsafeSubstitute( new TypeProjectionImpl(originalProjectionKind, flexibility.getLowerBound()), recursionDepth + 1); TypeProjection substitutedUpper = unsafeSubstitute( new TypeProjectionImpl(originalProjectionKind, flexibility.getUpperBound()), recursionDepth + 1); Variance substitutedProjectionKind = substitutedLower.getProjectionKind(); assert (substitutedProjectionKind == substitutedUpper.getProjectionKind()) && originalProjectionKind == Variance.INVARIANT || originalProjectionKind == substitutedProjectionKind : "Unexpected substituted projection kind: " + substitutedProjectionKind + "; original: " + originalProjectionKind; JetType substitutedFlexibleType = DelegatingFlexibleType.create( substitutedLower.getType(), substitutedUpper.getType(), flexibility.getExtraCapabilities()); return new TypeProjectionImpl(substitutedProjectionKind, substitutedFlexibleType); } if (KotlinBuiltIns.isNothing(type) || type.isError()) return originalProjection; if (replacement != null) { VarianceConflictType varianceConflict = conflictType(originalProjectionKind, replacement.getProjectionKind()); // Captured type might be substituted in an opposite projection: // out 'Captured (in Int)' = out Int // in 'Captured (out Int)' = in Int boolean allowVarianceConflict = CapturedTypeConstructorKt.isCaptured(type); if (!allowVarianceConflict) { //noinspection EnumSwitchStatementWhichMissesCases switch (varianceConflict) { case OUT_IN_IN_POSITION: throw new SubstitutionException("Out-projection in in-position"); case IN_IN_OUT_POSITION: // todo use the right type parameter variance and upper bound return new TypeProjectionImpl( Variance.OUT_VARIANCE, type.getConstructor().getBuiltIns().getNullableAnyType()); } } JetType substitutedType; CustomTypeVariable typeVariable = TypeCapabilitiesKt.getCustomTypeVariable(type); if (replacement.isStarProjection()) { return replacement; } else if (typeVariable != null) { substitutedType = typeVariable.substitutionResult(replacement.getType()); } else { // this is a simple type T or T?: if it's T, we should just take replacement, if T? - we // make replacement nullable substitutedType = TypeUtils.makeNullableIfNeeded(replacement.getType(), type.isMarkedNullable()); } // substitutionType.annotations = replacement.annotations ++ type.annotations if (!type.getAnnotations().isEmpty()) { Annotations typeAnnotations = filterOutUnsafeVariance(type.getAnnotations()); substitutedType = TypeUtilsKt.replaceAnnotations( substitutedType, new CompositeAnnotations(substitutedType.getAnnotations(), typeAnnotations)); } Variance resultingProjectionKind = varianceConflict == VarianceConflictType.NO_CONFLICT ? combine(originalProjectionKind, replacement.getProjectionKind()) : originalProjectionKind; return new TypeProjectionImpl(resultingProjectionKind, substitutedType); } // The type is not within the substitution range, i.e. Foo, Bar<T> etc. return substituteCompoundType(originalProjection, recursionDepth); }
public static boolean canHaveSubtypes(KotlinTypeChecker typeChecker, @NotNull KotlinType type) { if (type.isMarkedNullable()) { return true; } if (!type.getConstructor().isFinal()) { return true; } List<TypeParameterDescriptor> parameters = type.getConstructor().getParameters(); List<TypeProjection> arguments = type.getArguments(); for (int i = 0, parametersSize = parameters.size(); i < parametersSize; i++) { TypeParameterDescriptor parameterDescriptor = parameters.get(i); TypeProjection typeProjection = arguments.get(i); if (typeProjection.isStarProjection()) return true; Variance projectionKind = typeProjection.getProjectionKind(); KotlinType argument = typeProjection.getType(); switch (parameterDescriptor.getVariance()) { case INVARIANT: switch (projectionKind) { case INVARIANT: if (lowerThanBound(typeChecker, argument, parameterDescriptor) || canHaveSubtypes(typeChecker, argument)) { return true; } break; case IN_VARIANCE: if (lowerThanBound(typeChecker, argument, parameterDescriptor)) { return true; } break; case OUT_VARIANCE: if (canHaveSubtypes(typeChecker, argument)) { return true; } break; } break; case IN_VARIANCE: if (projectionKind != Variance.OUT_VARIANCE) { if (lowerThanBound(typeChecker, argument, parameterDescriptor)) { return true; } } else { if (canHaveSubtypes(typeChecker, argument)) { return true; } } break; case OUT_VARIANCE: if (projectionKind != Variance.IN_VARIANCE) { if (canHaveSubtypes(typeChecker, argument)) { return true; } } else { if (lowerThanBound(typeChecker, argument, parameterDescriptor)) { return true; } } break; } } return false; }