Incorrect panic message

[wikylyu]

Have a look at following code

package main

import (
	"context"
	"database/sql"

	"github.com/uptrace/bun"
	"github.com/uptrace/bun/dialect/pgdialect"
	"github.com/uptrace/bun/driver/pgdriver"
)

type TableA struct {
	bun.BaseModel `bun:"table:table_a"`
	UserID        int64 `bun:"user_id,pk,autoincrement" json:"user_id"`
}

type TableB struct {
	bun.BaseModel `bun:"table:table_b"`
	ID            int64 `bun:"id,pk,autoincrement" json:"id"`

	TableAID int64 `bun:"table_a_id,notnull" json:"table_a_id"`

	A *TableA `bun:"rel:belongs-to,join:table_a_id=id"`   // there's an error in this line. TableA's primary key is user_id, not id.
}

func main() {

	dsn := "postgres://postgres:@localhost:5432/test?sslmode=disable"
	// dsn := "unix://user:pass@dbname/var/run/postgresql/.s.PGSQL.5432"
	sqldb := sql.OpenDB(pgdriver.NewConnector(pgdriver.WithDSN(dsn)))

	db := bun.NewDB(sqldb, pgdialect.New())

	b := TableB{}
	if err := db.NewSelect().Model(&b).Relation(`A`).Limit(1).Scan(context.Background()); err != nil {
		return
	}

}

When I run that code. Panic occurs like below

panic: bun: TableB belongs-to A: TableB must have column table_a_id

goroutine 1 [running]:
github.com/uptrace/bun/schema.(*Table).belongsToRelation(0xc00017e160, 0xc00017eb00)
	/home/wiky/Downloads/temp/vendor/github.com/uptrace/bun/schema/table.go:535 +0xaf7
github.com/uptrace/bun/schema.(*Table).initRelation(0x68b720?, 0xc00017eb00, {0x674105?, 0x3?})
	/home/wiky/Downloads/temp/vendor/github.com/uptrace/bun/schema/table.go:452 +0xb2
github.com/uptrace/bun/schema.(*Table).tryRelation(0xc00017e160, 0xc00017eb00)
	/home/wiky/Downloads/temp/vendor/github.com/uptrace/bun/schema/table.go:431 +0x79
github.com/uptrace/bun/schema.(*Table).initRelations(0xc00017e160)
	/home/wiky/Downloads/temp/vendor/github.com/uptrace/bun/schema/table.go:416 +0x6f
github.com/uptrace/bun/schema.(*Table).init2(0x46c1c6?)
	/home/wiky/Downloads/temp/vendor/github.com/uptrace/bun/schema/table.go:130 +0x19
github.com/uptrace/bun/schema.(*tableInProgress).init2.func1()
	/home/wiky/Downloads/temp/vendor/github.com/uptrace/bun/schema/tables.go:34 +0x29
sync.(*Once).doSlow(0xc00009eb60?, 0xc00009ebe8?)
	/usr/lib/go-1.19/src/sync/once.go:74 +0xc2
sync.(*Once).Do(...)
	/usr/lib/go-1.19/src/sync/once.go:65
github.com/uptrace/bun/schema.(*tableInProgress).init2(0xc0000ac338?)
	/home/wiky/Downloads/temp/vendor/github.com/uptrace/bun/schema/tables.go:33 +0x5a
github.com/uptrace/bun/schema.(*Tables).table(0xc0000ac300, {0x7472c0?, 0x6acd80?}, 0x0)
	/home/wiky/Downloads/temp/vendor/github.com/uptrace/bun/schema/tables.go:104 +0x27f
github.com/uptrace/bun/schema.(*Tables).Get(...)
	/home/wiky/Downloads/temp/vendor/github.com/uptrace/bun/schema/tables.go:62
github.com/uptrace/bun.(*DB).Table(0x1?, {0x7472c0, 0x6acd80})
	/home/wiky/Downloads/temp/vendor/github.com/uptrace/bun/db.go:195 +0x45
github.com/uptrace/bun.newStructTableModelValue(0xc0000ac360, {0x678540?, 0xc0000a8ae0}, {0x6acd80?, 0xc0000a8ae0?, 0x422aa7?})
	/home/wiky/Downloads/temp/vendor/github.com/uptrace/bun/model_table_struct.go:46 +0x7e
github.com/uptrace/bun._newModel(0xc0000ac360, {0x678540?, 0xc0000a8ae0}, 0x0)
	/home/wiky/Downloads/temp/vendor/github.com/uptrace/bun/model.go:123 +0x7b4
github.com/uptrace/bun.newSingleModel(...)
	/home/wiky/Downloads/temp/vendor/github.com/uptrace/bun/model.go:75
github.com/uptrace/bun.(*baseQuery).setModel(0xc000180000, {0x678540?, 0xc0000a8ae0?})
	/home/wiky/Downloads/temp/vendor/github.com/uptrace/bun/query_base.go:163 +0x34
github.com/uptrace/bun.(*SelectQuery).Model(...)
	/home/wiky/Downloads/temp/vendor/github.com/uptrace/bun/query_select.go:60
main.main()
	/home/wiky/Downloads/temp/a.go:35 +0x16b
exit status 2

The problem is that panic message is incorrect.

panic: bun: TableB belongs-to A: TableB must have column table_a_id

TableB of course has column table_a_id. The right error message should be

bun: TableB belongs-to A:  TableA must have column id

[vmihailenco]

wikylyu sounds good. Could you send a PR with the fix?

[vmihailenco]

Merged, thanks.