Re: Ginq: combining join and aggregate functions

I will look into the issue later.

Could you submit a JIRA ticket to track the issue?

Here is the similar example, but its works, I am curious about the difference between them.

https://github.com/apache/groovy/blob/02ac82f92760357c0eb653ed2f1fa2f0a6dd65cc/subprojects/groovy-ginq/src/spec/test/org/apache/groovy/ginq/GinqTest.groovy#L4789

Cheers,
Daniel Sun

On 2024/10/05 17:16:02 Per Nyfelt wrote:
> Hi, I am trying to learn Ginq and are having problems with joining an 
> aggregation functions.
> 
> The following example illustrates the issue:
> 
> import java.time.LocalDate
> 
> class Warehouse {
>      int id
>      String name
>      Double price
>      int stock
> 
>      Warehouse(int id, String name, Double price, int stock) {
>        this.id = id
>        this.name = name
>        this.price = price
>        this.stock = stock
>      }
>    }
> 
>    class Sales {
>      LocalDate date
>      int item
> 
>      Sales(LocalDate date, int item) {
>        this.date = date
>        this.item = item
>      }
>    }
> 
> 
> List<Warehouse> warehouse = [
>      new Warehouse(1, 'Orange', 11, 2),
>      new Warehouse(2, 'Apple', 6, 3),
>      new Warehouse(3, 'Banana', 4, 1),
>      new Warehouse(4, 'Mango', 29, 10)
> ]
> List<Sales> sales = [
>      new Sales(LocalDate.of(2024, 5, 1), 1),
>      new Sales(LocalDate.of(2024, 5, 2), 1),
>      new Sales(LocalDate.of(2024, 5, 3), 3)
> ]
> def q = GQ {
>    from s in sales
>    join w in warehouse on w.id == s.item
>    select w.name, w.price
> }
> // so far so good, the following works:
> assert  [['Orange', 11.0], ['Orange', 11.0], ['Banana', 4.0]] == q.toList()
> 
> // now try to summarize by name
> def qSum = GQ {
>    from s in sales
>    join w in warehouse on w.id == s.item
>    groupby w.name
>    select w.name, sum(w.price)
> }
> // Fails with Exception evaluating property 'price' for groovy.lang.Tuple2,
> // Reason: groovy.lang.MissingPropertyException: No such property: price 
> for class: Sales
> assert  [['Orange', 22.0], ['Banana', 4.0]] == qSum.toList()
> 
> So for some reason ginq thinks it will find the price property in the 
> Sales class instead of in the Warehouse class so w.price here is not 
> understood. What is the right way to write it?
> 
> Regards,
> 
> Per
> 
>