@Nullable public static PsiType getExpectedClosureReturnType(GrClosableBlock closure) { final Set<PsiType> expectedTypes = getDefaultExpectedTypes(closure); List<PsiType> expectedReturnTypes = new ArrayList<PsiType>(); for (PsiType expectedType : expectedTypes) { if (!(expectedType instanceof PsiClassType)) return null; final PsiClassType.ClassResolveResult resolveResult = ((PsiClassType) expectedType).resolveGenerics(); final PsiClass resolved = resolveResult.getElement(); if (resolved == null || !(GroovyCommonClassNames.GROOVY_LANG_CLOSURE.equals(resolved.getQualifiedName()))) return null; final PsiTypeParameter[] typeParameters = resolved.getTypeParameters(); if (typeParameters.length != 1) return null; final PsiTypeParameter expected = typeParameters[0]; final PsiType expectedReturnType = resolveResult.getSubstitutor().substitute(expected); if (expectedReturnType == PsiType.VOID || expectedReturnType == null) return null; expectedReturnTypes.add(expectedReturnType); } return TypesUtil.getLeastUpperBoundNullable(expectedReturnTypes, closure.getManager()); }
@Nullable private static Boolean isAssignableForNativeTypes( @NotNull PsiType lType, @NotNull PsiClassType rType, @NotNull PsiElement context) { if (!(lType instanceof PsiClassType)) return null; final PsiClassType.ClassResolveResult leftResult = ((PsiClassType) lType).resolveGenerics(); final PsiClassType.ClassResolveResult rightResult = rType.resolveGenerics(); final PsiClass leftClass = leftResult.getElement(); PsiClass rightClass = rightResult.getElement(); if (rightClass == null || leftClass == null) return null; if (!InheritanceUtil.isInheritorOrSelf(rightClass, leftClass, true)) return Boolean.FALSE; PsiSubstitutor rightSubstitutor = rightResult.getSubstitutor(); if (!leftClass.hasTypeParameters()) return Boolean.TRUE; PsiSubstitutor leftSubstitutor = leftResult.getSubstitutor(); if (!leftClass.getManager().areElementsEquivalent(leftClass, rightClass)) { rightSubstitutor = TypeConversionUtil.getSuperClassSubstitutor(leftClass, rightClass, rightSubstitutor); rightClass = leftClass; } else if (!rightClass.hasTypeParameters()) return Boolean.TRUE; Iterator<PsiTypeParameter> li = PsiUtil.typeParametersIterator(leftClass); Iterator<PsiTypeParameter> ri = PsiUtil.typeParametersIterator(rightClass); while (li.hasNext()) { if (!ri.hasNext()) return Boolean.FALSE; PsiTypeParameter lp = li.next(); PsiTypeParameter rp = ri.next(); final PsiType typeLeft = leftSubstitutor.substitute(lp); if (typeLeft == null) continue; final PsiType typeRight = rightSubstitutor.substituteWithBoundsPromotion(rp); if (typeRight == null) { return Boolean.TRUE; } if (!isAssignableWithoutConversions(typeLeft, typeRight, context)) return Boolean.FALSE; } return Boolean.TRUE; }