Java Code Examples for org.eclipse.xtext.xbase.typesystem.InferredTypeIndicator#isInferred()

/**
 * Returns <code>null</code> if the given operation declares it's own return type or if it does not override
 * another operation.
 */
/* @Nullable */
@SuppressWarnings("unused")
protected LightweightTypeReference getReturnTypeOfOverriddenOperation(JvmOperation operation, ResolvedTypes resolvedTypes, IFeatureScopeSession session) {
	if (operation.getVisibility() == JvmVisibility.PRIVATE)
		return null;
	if (InferredTypeIndicator.isInferred(operation.getReturnType())) {
		LightweightTypeReference declaringType = resolvedTypes.getActualType(operation.getDeclaringType());
		if (declaringType == null) {
			throw new IllegalStateException("Cannot determine declaring type of operation: " + operation);
		}
		LightweightTypeReference result = overrideHelper.getReturnTypeOfOverriddenOperation(operation, declaringType);
		return result;
	}
	return null;
}
 

/**
 * Initializes the type inference strategy for the cache field for create extensions.
 */
@Override
protected void _doPrepare(ResolvedTypes resolvedTypes, IFeatureScopeSession featureScopeSession, JvmField field,
		Map<JvmIdentifiableElement, ResolvedTypes> resolvedTypesByContext) {
	JvmTypeReference knownType = field.getType();
	if (InferredTypeIndicator.isInferred(knownType)) {
		XComputedTypeReference castedKnownType = (XComputedTypeReference) knownType;
		EObject sourceElement = associations.getPrimarySourceElement(field);
		if (sourceElement instanceof XtendFunction) {
			XtendFunction function = (XtendFunction) sourceElement;
			if (function.getCreateExtensionInfo() != null) {
				JvmOperation operation = associations.getDirectlyInferredOperation(function);
				if (operation != null) {
					declareTypeParameters(resolvedTypes, field, resolvedTypesByContext);
					XComputedTypeReference fieldType = getServices().getXtypeFactory().createXComputedTypeReference();
					fieldType.setTypeProvider(new CreateCacheFieldTypeReferenceProvider(operation, resolvedTypes, featureScopeSession));
					castedKnownType.setEquivalent(fieldType);
					return;
				}
			}
		}
	}
	super._doPrepare(resolvedTypes, featureScopeSession, field, resolvedTypesByContext);
	doPrepareLocalTypes(resolvedTypesByContext.get(field), featureScopeSession, field, resolvedTypesByContext);
}
 

@Override
/* @Nullable */
protected LightweightTypeReference getExpectedType() {
	LightweightTypeReference expectedType = super.getExpectedType();
	if (expectedType != null) {
		return expectedType;
	}
	if (dispatcher != null) {
		JvmOperation operation = (JvmOperation) getMember();
		if (!InferredTypeIndicator.isInferred(dispatcher.getReturnType())) {
			LightweightTypeReference result = getResolvedTypes().getActualType(dispatcher);
			if (result != null)
				InferredTypeIndicator.resolveTo(operation.getReturnType(), result.toJavaCompliantTypeReference());
			return result;
		}
	}
	return inheritedExpectedType;
}
 

protected IEObjectDescription doGetSingleElement(JvmDeclaredType declarator, QualifiedName name, String firstSegment, int dollarIndex) {
	if (declarator.isLocal()) {
		JvmTypeReference superTypeReference = Iterables.getLast(declarator.getSuperTypes());
		if (InferredTypeIndicator.isInferred(superTypeReference))
			return findNestedTypeInLocalTypeNonResolving(declarator, name, firstSegment, dollarIndex);
	}
	
	Iterable<JvmDeclaredType> nestedTypes = declarator.findAllNestedTypesByName(firstSegment);
	for(JvmDeclaredType nested: nestedTypes) {
		JvmType nestedType = findNestedType(nested, 0, name);
		if (nestedType != null) {
			return toDescription(name, nestedType, dollarIndex, 0);
		}
	}
	return null;
}
 

/** Clone the given type reference that is associated to another Xtext resource.
 *
 * <p>This function ensures that the resource of the reference clone is not pointing
 * to the resource of the original reference.
 *
 * <p>This function calls {@link JvmTypesBuilder#cloneWithProxies(JvmTypeReference)} or
 * {@link #cloneWithTypeParametersAndProxies(JvmTypeReference, JvmExecutable)} if the
 * {@code target} is {@code null} for the first, and not {@code null} for the second.
 *
 * @param type the source type.
 * @param target the operation for which the type is clone, or {@code null} if not relevant.
 * @return the result type, i.e. a copy of the source type.
 */
protected JvmTypeReference cloneWithProxiesFromOtherResource(JvmTypeReference type, JvmOperation target) {
	if (type == null) {
		return this._typeReferenceBuilder.typeRef(Void.TYPE);
	}
	// Do not clone inferred types because they are not yet resolved and it is located within the current resource.
	if (InferredTypeIndicator.isInferred(type)) {
		return type;
	}
	// Do not clone primitive types because the associated resource to the type reference will not be correct.
	final String id = type.getIdentifier();
	if (Objects.equal(id, Void.TYPE.getName())) {
		return this._typeReferenceBuilder.typeRef(Void.TYPE);
	}
	if (this.services.getPrimitives().isPrimitive(type)) {
		return this._typeReferenceBuilder.typeRef(id);
	}
	// Clone the type
	if (target != null) {
		return cloneWithTypeParametersAndProxies(type, target);
	}
	return this.typeBuilder.cloneWithProxies(type);
}
 

private JvmTypeReference ensureValidType(Resource targetResource, JvmTypeReference returnType) {
	// No return type could be inferred => assume "void"
	if (returnType == null) {
		return this._typeReferenceBuilder.typeRef(Void.TYPE);
	}
	// The given type is not associated to the target resource => force relocation.
	final Resource returnTypeResource = returnType.eResource();
	if (returnTypeResource != null && !Objects.equal(returnType.eResource(), targetResource)) {
		return this.typeBuilder.cloneWithProxies(returnType);
	}
	// A return type was inferred => use it as-is because it is not yet resolved to the concrete type.
	if (InferredTypeIndicator.isInferred(returnType)) {
		return returnType;
	}
	// A return was inferred and resolved => use it.
	return this.typeBuilder.cloneWithProxies(returnType);
}
 

protected AbstractDemandTypeReferenceProvider getComputedTypeReference(JvmTypeReference knownType) {
	if (InferredTypeIndicator.isInferred(knownType)) {
		XComputedTypeReference casted = (XComputedTypeReference) knownType;
		JvmTypeReference equivalent = casted.getEquivalent();
		if (equivalent instanceof XComputedTypeReference) {
			IJvmTypeReferenceProvider typeProvider = ((XComputedTypeReference) equivalent).getTypeProvider();
			if (typeProvider instanceof AbstractDemandTypeReferenceProvider) {
				return (AbstractDemandTypeReferenceProvider) typeProvider;
			}
		}
	}
	return null;
}
 

/**
 * Returns the expression that will be used to infer the given type from. If the type is 
 * already resolved, the result will be null. If no expression can be determined, null is
 * also returned.
 */
protected XExpression getInferredFrom(JvmTypeReference typeReference) {
	if (InferredTypeIndicator.isInferred(typeReference)) {
		XComputedTypeReference computed = (XComputedTypeReference) typeReference;
		if (computed.getEquivalent() instanceof XComputedTypeReference) {
			XComputedTypeReference inferred = (XComputedTypeReference) computed.getEquivalent();
			IJvmTypeReferenceProvider typeProvider = inferred.getTypeProvider();
			if (typeProvider instanceof DemandTypeReferenceProvider) {
				return ((DemandTypeReferenceProvider) typeProvider).expression;
			}
		}
	}
	return null;
}
 

/**
 * Detects whether the type reference refers to primitive boolean.
 * 
 * @since 2.9
 */
protected boolean isPrimitiveBoolean(JvmTypeReference typeRef) {
	if (InferredTypeIndicator.isInferred(typeRef)) {
		return false;
	}
	
	return typeRef != null && typeRef.getType() != null &&
			!typeRef.getType().eIsProxy() &&
			"boolean".equals(typeRef.getType().getIdentifier());
}
 

protected void resolveDispatchCaseTypes(JvmOperation dispatcher, List<JvmOperation> dispatchCases, LightweightTypeReference type,
		IFeatureScopeSession featureScopeSession) {
	if (InferredTypeIndicator.isInferred(dispatcher.getReturnType())) {
		InferredTypeIndicator.resolveTo(dispatcher.getReturnType(), toJavaCompliantTypeReference(type, featureScopeSession));
	}
	for (JvmOperation dispatchCase : dispatchCases) {
		if (InferredTypeIndicator.isInferred(dispatchCase.getReturnType())) {
			InferredTypeIndicator.resolveTo(dispatchCase.getReturnType(), toJavaCompliantTypeReference(type, featureScopeSession));
		}
	}
}
 

@Override
protected LightweightTypeReference getReturnTypeOfOverriddenOperation(JvmOperation operation,
		ResolvedTypes resolvedTypes, IFeatureScopeSession session) {
	if (operation.getVisibility() == JvmVisibility.PRIVATE)
		return null;
	if (InferredTypeIndicator.isInferred(operation.getReturnType())) {
		LightweightTypeReference declaringType = resolvedTypes.getActualType(operation.getDeclaringType());
		if (declaringType == null) {
			throw new IllegalStateException("Cannot determine declaring type of operation: " + operation);
		}
		BottomResolvedOperation resolvedOperation = new BottomResolvedOperation(operation, declaringType, overrideTester);
		List<IResolvedOperation> overriddenMethods = resolvedOperation.getOverriddenAndImplementedMethods();
		if (overriddenMethods.isEmpty())
			return null;
		IResolvedOperation overriddenMethod = overriddenMethods.get(0);
		JvmOperation declaration = overriddenMethod.getDeclaration();
		XExpression inferredFrom = getInferredFrom(declaration.getReturnType());
		// guard against active annotations that put an expression into a second method
		// namely in a synthesized super type - in that case, the expression should not be
		// inferred in the context of the super type but the subtype thus the return type
		// of a super method has to be ignored
		
		// see https://bugs.eclipse.org/bugs/show_bug.cgi?id=439535
		if (inferredFrom != null && (inferredFrom == getInferredFrom(operation.getReturnType()) || isHandled(inferredFrom))) {
			return null;
		}
		LightweightTypeReference result = overriddenMethod.getResolvedReturnType();
		return result;
	}
	return null;
}
 

/**
 * Returns <code>null</code> if the given operation declares it's own return type or if it does not override
 * another operation.
 * 
 * TODO support this case:
 * 
 * <pre>
 * interface I {
 *   String m()
 *   String m2()
 * }
 * class A {
 *   CharSequence m()
 *   int m2()
 * }
 * class B extends A implements I {
 *   m() will expect String since this is the best choice
 *   m2() will expect int since this is actually overridden and not compatible to String from I#m2
 * }
 * </pre>
 */
/* @Nullable */
public LightweightTypeReference getReturnTypeOfOverriddenOperation(JvmOperation operation, ITypeReferenceOwner owner, IVisibilityHelper visibilityHelper) {
	if (operation.getVisibility() == JvmVisibility.PRIVATE || !InferredTypeIndicator.isInferred(operation.getReturnType())) {
		return null;
	}
	LightweightTypeReference declaringType = owner.newParameterizedTypeReference(operation.getDeclaringType());
	TypeParameterSubstitutor<?> substitutor = createSubstitutor(owner, declaringType);
	JvmOperation overriddenOperation = findOverriddenOperation(operation, declaringType, substitutor, owner, visibilityHelper);
	if (overriddenOperation != null) {
		return substitutor.substitute(owner.toLightweightTypeReference(overriddenOperation.getReturnType()));
	}
	return null;
}
 

/**
 * Returns <code>null</code> if the given operation declares it's own return type or if it does not override
 * another operation.
 * 
 * TODO support this case:
 * 
 * <pre>
 * interface I {
 *   String m()
 *   String m2()
 * }
 * class A {
 *   CharSequence m()
 *   int m2()
 * }
 * class B extends A implements I {
 *   m() will expect String since this is the best choice
 *   m2() will expect int since this is actually overridden and not compatible to String from I#m2
 * }
 * </pre>
 */
/* @Nullable */
public LightweightTypeReference getReturnTypeOfOverriddenOperation(JvmOperation operation, LightweightTypeReference context) {
	if (operation.getVisibility() == JvmVisibility.PRIVATE || !InferredTypeIndicator.isInferred(operation.getReturnType())) {
		return null;
	}
	BottomResolvedOperation resolvedOperation = new BottomResolvedOperation(operation, context, overrideTester);
	List<IResolvedOperation> overriddenMethods = resolvedOperation.getOverriddenAndImplementedMethods();
	if (overriddenMethods.isEmpty())
		return null;
	LightweightTypeReference result = overriddenMethods.get(0).getResolvedReturnType();
	return result;
}