public static PsiType captureReturnType(
PsiMethodCallExpression call,
PsiMethod method,
PsiType ret,
JavaResolveResult result,
LanguageLevel languageLevel) {
PsiSubstitutor substitutor = result.getSubstitutor();
PsiType substitutedReturnType = substitutor.substitute(ret);
if (substitutedReturnType == null) {
return TypeConversionUtil.erasure(ret);
}
if (InferenceSession.wasUncheckedConversionPerformed(call)) {
// 18.5.2
// if unchecked conversion was necessary, then this substitution provides the parameter types
// of the invocation type,
// while the return type and thrown types are given by the erasure of m's type (without
// applying θ').
// due to https://bugs.openjdk.java.net/browse/JDK-8135087 erasure is called on
// substitutedReturnType and not on ret type itself as by spec
return TypeConversionUtil.erasure(substitutedReturnType);
}
// 15.12.2.6. Method Invocation Type
// If unchecked conversion was necessary for the method to be applicable,
// the parameter types of the invocation type are the parameter types of the method's type,
// and the return type and thrown types are given by the erasures of the return type and thrown
// types of the method's type.
if (!languageLevel.isAtLeast(LanguageLevel.JDK_1_8)
&& (method.hasTypeParameters()
|| JavaVersionService.getInstance().isAtLeast(call, JavaSdkVersion.JDK_1_8))
&& result instanceof MethodCandidateInfo
&& ((MethodCandidateInfo) result).isApplicable()) {
final PsiType[] args = call.getArgumentList().getExpressionTypes();
final boolean allowUncheckedConversion = false;
final int applicabilityLevel =
PsiUtil.getApplicabilityLevel(
method, substitutor, args, languageLevel, allowUncheckedConversion, true);
if (applicabilityLevel == MethodCandidateInfo.ApplicabilityLevel.NOT_APPLICABLE) {
return TypeConversionUtil.erasure(substitutedReturnType);
}
}
if (PsiUtil.isRawSubstitutor(method, substitutor)) {
final PsiType returnTypeErasure = TypeConversionUtil.erasure(ret);
if (Comparing.equal(TypeConversionUtil.erasure(substitutedReturnType), returnTypeErasure)) {
return returnTypeErasure;
}
}
return PsiUtil.captureToplevelWildcards(substitutedReturnType, call);
}
