private void reportNullableReturns(
      DataFlowInstructionVisitor visitor,
      ProblemsHolder holder,
      Set<PsiElement> reportedAnchors,
      @NotNull PsiElement block) {
    final PsiMethod method = getScopeMethod(block);
    if (method == null || NullableStuffInspectionBase.isNullableNotInferred(method, true)) return;

    boolean notNullRequired = NullableNotNullManager.isNotNull(method);
    if (!notNullRequired && !SUGGEST_NULLABLE_ANNOTATIONS) return;

    PsiType returnType = method.getReturnType();
    // no warnings in void lambdas, where the expression is not returned anyway
    if (block instanceof PsiExpression
        && block.getParent() instanceof PsiLambdaExpression
        && returnType == PsiType.VOID) return;

    // no warnings for Void methods, where only null can be possibly returned
    if (returnType == null || returnType.equalsToText(CommonClassNames.JAVA_LANG_VOID)) return;

    for (PsiElement statement : visitor.getProblems(NullabilityProblem.nullableReturn)) {
      assert statement instanceof PsiExpression;
      final PsiExpression expr = (PsiExpression) statement;
      if (!reportedAnchors.add(expr)) continue;

      if (notNullRequired) {
        final String text =
            isNullLiteralExpression(expr)
                ? InspectionsBundle.message("dataflow.message.return.null.from.notnull")
                : InspectionsBundle.message("dataflow.message.return.nullable.from.notnull");
        holder.registerProblem(expr, text);
      } else if (AnnotationUtil.isAnnotatingApplicable(statement)) {
        final NullableNotNullManager manager =
            NullableNotNullManager.getInstance(expr.getProject());
        final String defaultNullable = manager.getDefaultNullable();
        final String presentableNullable = StringUtil.getShortName(defaultNullable);
        final String text =
            isNullLiteralExpression(expr)
                ? InspectionsBundle.message(
                    "dataflow.message.return.null.from.notnullable", presentableNullable)
                : InspectionsBundle.message(
                    "dataflow.message.return.nullable.from.notnullable", presentableNullable);
        final LocalQuickFix[] fixes =
            PsiTreeUtil.getParentOfType(expr, PsiMethod.class, PsiLambdaExpression.class)
                    instanceof PsiLambdaExpression
                ? LocalQuickFix.EMPTY_ARRAY
                : new LocalQuickFix[] {
                  new AnnotateMethodFix(
                      defaultNullable, ArrayUtil.toStringArray(manager.getNotNulls())) {
                    @Override
                    public int shouldAnnotateBaseMethod(
                        PsiMethod method, PsiMethod superMethod, Project project) {
                      return 1;
                    }
                  }
                };
        holder.registerProblem(expr, text, fixes);
      }
    }
  }
  private void reportNullableArgumentsPassedToNonAnnotated(
      DataFlowInstructionVisitor visitor, ProblemsHolder holder, Set<PsiElement> reportedAnchors) {
    for (PsiElement expr :
        visitor.getProblems(NullabilityProblem.passingNullableArgumentToNonAnnotatedParameter)) {
      if (reportedAnchors.contains(expr)) continue;

      final String text =
          isNullLiteralExpression(expr)
              ? "Passing <code>null</code> argument to non annotated parameter"
              : "Argument <code>#ref</code> #loc might be null but passed to non annotated parameter";
      LocalQuickFix[] fixes =
          createNPEFixes((PsiExpression) expr, (PsiExpression) expr, holder.isOnTheFly());
      final PsiElement parent = expr.getParent();
      if (parent instanceof PsiExpressionList) {
        final int idx = ArrayUtilRt.find(((PsiExpressionList) parent).getExpressions(), expr);
        if (idx > -1) {
          final PsiElement gParent = parent.getParent();
          if (gParent instanceof PsiCallExpression) {
            final PsiMethod psiMethod = ((PsiCallExpression) gParent).resolveMethod();
            if (psiMethod != null
                && psiMethod.getManager().isInProject(psiMethod)
                && AnnotationUtil.isAnnotatingApplicable(psiMethod)) {
              final PsiParameter[] parameters = psiMethod.getParameterList().getParameters();
              if (idx < parameters.length) {
                final AddNullableAnnotationFix addNullableAnnotationFix =
                    new AddNullableAnnotationFix(parameters[idx]);
                fixes =
                    fixes == null
                        ? new LocalQuickFix[] {addNullableAnnotationFix}
                        : ArrayUtil.append(fixes, addNullableAnnotationFix);
                holder.registerProblem(expr, text, fixes);
                reportedAnchors.add(expr);
              }
            }
          }
        }
      }
    }
  }