From 392ba63bc5d2fe483c4914ab18595f5ea1f2d80c Mon Sep 17 00:00:00 2001
From: go-jet <zer0.sub@protonmail.com>
Date: Thu, 30 Dec 2021 16:23:59 +0100
Subject: [PATCH] Add helper method to set ProjectionList alias.

---
 internal/jet/projection.go  | 22 ++++++++++++++
 tests/postgres/with_test.go | 60 +++++++++++++++++++++++++++++++++++++
 2 files changed, 82 insertions(+)

diff --git a/internal/jet/projection.go b/internal/jet/projection.go
index b85702f..16abe5b 100644
--- a/internal/jet/projection.go
+++ b/internal/jet/projection.go
@@ -1,5 +1,7 @@
 package jet
 
+import "strings"
+
 // Projection is interface for all projection types. Types that can be part of, for instance SELECT clause.
 type Projection interface {
 	serializeForProjection(statement StatementType, out *SQLBuilder)
@@ -27,3 +29,23 @@ func (cl ProjectionList) fromImpl(subQuery SelectTable) Projection {
 func (cl ProjectionList) serializeForProjection(statement StatementType, out *SQLBuilder) {
 	SerializeProjectionList(statement, cl, out)
 }
+
+// As is used to set aliases of the projection list. alias should be in the form 'name' or 'name.*'.
+// For instance: If projection list has a column 'Artist.Name', and alias is 'Musician.*', returned projection list will
+// have column wrapped in alias 'Musician.Name'.
+func (cl ProjectionList) As(alias string) ProjectionList {
+	alias = strings.TrimRight(alias, ".*")
+
+	newProjectionList := ProjectionList{}
+
+	for _, projection := range cl {
+		switch p := projection.(type) {
+		case ProjectionList:
+			newProjectionList = append(newProjectionList, p.As(alias))
+		case ColumnExpression:
+			newProjectionList = append(newProjectionList, newAlias(p, alias+"."+p.Name()))
+		}
+	}
+
+	return newProjectionList
+}
diff --git a/tests/postgres/with_test.go b/tests/postgres/with_test.go
index 27d5ce0..3b682d8 100644
--- a/tests/postgres/with_test.go
+++ b/tests/postgres/with_test.go
@@ -2,6 +2,7 @@ package postgres
 
 import (
 	"context"
+	"fmt"
 	"github.com/go-jet/jet/v2/internal/testutils"
 	. "github.com/go-jet/jet/v2/postgres"
 	"github.com/go-jet/jet/v2/tests/.gentestdata/jetdb/northwind/model"
@@ -746,3 +747,62 @@ WHERE not_from_us_or_aus."suppliers.contact_name" != 'John';
 	require.NoError(t, err)
 	require.Len(t, dest, 11)
 }
+
+func TestWitStatement_CTE_NotMaterialized(t *testing.T) {
+	orders1 := CTE("orders1")
+	orders1ID := Orders.OrderID.From(orders1)
+	orders2 := orders1.ALIAS("orders2")
+	orders2ID := Orders.OrderID.From(orders2)
+
+	stmt := WITH(
+		orders1.AS_NOT_MATERIALIZED(
+			SELECT(
+				Orders.OrderID,
+				Orders.EmployeeID,
+				Orders.ShipCity,
+			).FROM(
+				Orders,
+			),
+		),
+	)(
+		SELECT(
+			orders1.AllColumns().As("orders1.*"),
+			orders2.AllColumns().As("orders2.*"),
+		).FROM(
+			orders1.
+				INNER_JOIN(orders2, orders1ID.EQ(orders2ID)),
+		).WHERE(
+			orders1ID.LT(Int(10320)),
+		),
+	)
+
+	// fmt.Println(stmt.Sql())
+
+	testutils.AssertStatementSql(t, stmt, `
+WITH orders1 AS NOT MATERIALIZED (
+     SELECT orders.order_id AS "orders.order_id",
+          orders.employee_id AS "orders.employee_id",
+          orders.ship_city AS "orders.ship_city"
+     FROM northwind.orders
+)
+SELECT orders1."orders.order_id" AS "orders1.order_id",
+     orders1."orders.employee_id" AS "orders1.employee_id",
+     orders1."orders.ship_city" AS "orders1.ship_city",
+     orders2."orders.order_id" AS "orders2.order_id",
+     orders2."orders.employee_id" AS "orders2.employee_id",
+     orders2."orders.ship_city" AS "orders2.ship_city"
+FROM orders1
+     INNER JOIN orders1 AS orders2 ON (orders1."orders.order_id" = orders2."orders.order_id")
+WHERE orders1."orders.order_id" < $1;
+`)
+
+	var dest []struct {
+		Orders1 model.Orders `alias:"orders1.*"`
+		Orders2 model.Orders `alias:"orders2.*"`
+	}
+
+	err := stmt.Query(db, &dest)
+	require.NoError(t, err)
+	require.Len(t, dest, 72)
+	fmt.Println(len(dest))
+}