Cannot use Func within CTE - Can't export unaliased expression subQuery

[dragondgold]

Describe the bug
When using a custom Func within a CTE like this:

func ARRAY_AGG_ORDER_BY(a Expression, b Expression) Expression {
	return Func("array_agg", CustomExpression(a, Token("ORDER BY"), b))
}

reservationsCTE := CTE("reservations")

stmtTest := WITH(
	reservationsCTE.AS(
		Schedules.SELECT(
			ARRAY_AGG_ORDER_BY(Users.Name, Users.Name),
		).FROM(
			Schedules.
				INNER_JOIN(Users, Users.ID.EQ(ScheduleSlots.UserID)),
		).GROUP_BY(Schedules.CreatedByUserID),
	),
)(
	SELECT(reservationsCTE.AllColumns()).
		FROM(reservationsCTE),
)

I get the following panic:

panic: jet: can't export unaliased expression subQuery: reservations, expression: array_agg(users.name ORDER BY users.name) [recovered]
	panic: jet: can't export unaliased expression subQuery: reservations, expression: array_agg(users.name ORDER BY users.name)

goroutine 5 [running]:
testing.tRunner.func1.2({0x1010076c0, 0x14000262260})
	/usr/local/go/src/testing/testing.go:1632 +0x3c0
testing.tRunner.func1()
	/usr/local/go/src/testing/testing.go:1635 +0x57c
panic({0x1010076c0?, 0x14000262260?})
	/usr/local/go/src/runtime/panic.go:785 +0xf0
github.com/go-jet/jet/v2/internal/jet.(*ExpressionInterfaceImpl).fromImpl(0x14000266c80, {0x101092a10, 0x14000266d00})
	/Users/andrestorti/go/pkg/mod/github.com/go-jet/jet/[email protected]/internal/jet/expression.go:38 +0x174
github.com/go-jet/jet/v2/internal/jet.ProjectionList.fromImpl({0x140002621c0, 0x1, 0x1}, {0x101092a10, 0x14000266d00})
	/Users/andrestorti/go/pkg/mod/github.com/go-jet/jet/[email protected]/internal/jet/projection.go:21 +0xc8
github.com/go-jet/jet/v2/internal/jet.selectTableImpl.AllColumns({{0x127e93880, 0x14000260580}, {0x100f8f90f, 0xc}, {0x0, 0x0, 0x0}})
	/Users/andrestorti/go/pkg/mod/github.com/go-jet/jet/[email protected]/internal/jet/select_table.go:44 +0xe4
github.com/test/core/pkg/repositories/reports.(*ReportsRepository).GetReservationsReport(0x101254840, {0x101092968, 0x101254840}, {0x100f9a8d0, 0x29}, {0x401fc58, 0xededd1f4b, 0x0}, {0x4020040, 0xedf04ac4b, ...})
	/Users/andrestorti/test/core/pkg/repositories/reports/reservations.go:47 +0xac8
github.com/test/core/pkg/repositories/reports_test.TestGetReservations(0x1400023c4e0)
	/Users/andrestorti/test/core/pkg/repositories/reports/reservations_test.go:13 +0xd4
testing.tRunner(0x1400023c4e0, 0x10108ef80)
	/usr/local/go/src/testing/testing.go:1690 +0x1a8
created by testing.(*T).Run in goroutine 1
	/usr/local/go/src/testing/testing.go:1743 +0x668
Process 83174 has exited with status 2

This does not happen when using the custom Func outside a CTE

Environment:

• OS: macosx
• Database: postgres
• Database driver: pgx
• Jet version 2.12.0

[houten11]

As the error indicates, you need to alias your expression:

		Schedules.SELECT(
			ARRAY_AGG_ORDER_BY(Users.Name, Users.Name).AS("foo"),
		)

[dragondgold]

As the error indicates, you need to alias your expression:

		Schedules.SELECT(
			ARRAY_AGG_ORDER_BY(Users.Name, Users.Name).AS("foo"),
		)

Ohhhh got it, but why does it work without an explicit alias when not used within a CTE?

[go-jet]

In this line:

	SELECT(reservationsCTE.AllColumns()).

you're referring to a projection from a CTE. Since the projection is not named, it cannot be referenced.