private static @Nullable PsiMethodCallExpression getFilterToMerge(PsiMethodCallExpression methodCallExpression) {
    final PsiMethodCallExpression prevCall = MethodCallUtils.getQualifierMethodCall(methodCallExpression);
    if (prevCall != null && isFilterCall(prevCall)) {
      return prevCall;
    }

    final PsiMethodCallExpression nextCall = ExpressionUtils.getCallForQualifier(methodCallExpression);
    if (nextCall != null && isFilterCall(nextCall)) {
      return nextCall;
    }
    return null;
  }
private static @Nullable PsiMethodCallExpression getFilterToMerge(PsiMethodCallExpression methodCallExpression)