private void checkCollectionNullityOnAssignment(@NotNull PsiElement errorElement,
                                                      @Nullable PsiType expectedType,
                                                      @Nullable PsiExpression assignedExpression) {
        if (assignedExpression == null) return;

        checkCollectionNullityOnAssignment(errorElement, expectedType, assignedExpression.getType());
      }
private void checkCollectionNullityOnAssignment(@NotNull PsiElement errorElement,
                                                      @Nullable PsiType expectedType,
                                                      @Nullable PsiExpression assignedExpression)