Pg to bun (#148)

* start moving to bun

* changing more stuff

* more

* and yet more

* tests passing

* seems stable now

* more big changes

* small fix

* little fixes

vendor/github.com/uptrace/bun/model_scan.go

@@ -0,0 +1,54 @@
+package bun
+
+import (
+	"context"
+	"database/sql"
+	"reflect"
+)
+
+type scanModel struct {
+	db *DB
+
+	dest      []interface{}
+	scanIndex int
+}
+
+var _ model = (*scanModel)(nil)
+
+func newScanModel(db *DB, dest []interface{}) *scanModel {
+	return &scanModel{
+		db:   db,
+		dest: dest,
+	}
+}
+
+func (m *scanModel) Value() interface{} {
+	return m.dest
+}
+
+func (m *scanModel) ScanRows(ctx context.Context, rows *sql.Rows) (int, error) {
+	if !rows.Next() {
+		return 0, rows.Err()
+	}
+
+	dest := makeDest(m, len(m.dest))
+
+	m.scanIndex = 0
+	if err := rows.Scan(dest...); err != nil {
+		return 0, err
+	}
+
+	return 1, nil
+}
+
+func (m *scanModel) ScanRow(ctx context.Context, rows *sql.Rows) error {
+	return rows.Scan(m.dest...)
+}
+
+func (m *scanModel) Scan(src interface{}) error {
+	dest := reflect.ValueOf(m.dest[m.scanIndex])
+	m.scanIndex++
+
+	scanner := m.db.dialect.Scanner(dest.Type())
+	return scanner(dest, src)
+}