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_map_slice.go

@@ -0,0 +1,162 @@
+package bun
+
+import (
+	"context"
+	"database/sql"
+	"errors"
+	"sort"
+
+	"github.com/uptrace/bun/dialect/feature"
+	"github.com/uptrace/bun/schema"
+)
+
+type mapSliceModel struct {
+	mapModel
+	dest *[]map[string]interface{}
+
+	keys []string
+}
+
+var _ model = (*mapSliceModel)(nil)
+
+func newMapSliceModel(db *DB, dest *[]map[string]interface{}) *mapSliceModel {
+	return &mapSliceModel{
+		mapModel: mapModel{
+			db: db,
+		},
+		dest: dest,
+	}
+}
+
+func (m *mapSliceModel) Value() interface{} {
+	return m.dest
+}
+
+func (m *mapSliceModel) SetCap(cap int) {
+	if cap > 100 {
+		cap = 100
+	}
+	if slice := *m.dest; len(slice) < cap {
+		*m.dest = make([]map[string]interface{}, 0, cap)
+	}
+}
+
+func (m *mapSliceModel) ScanRows(ctx context.Context, rows *sql.Rows) (int, error) {
+	columns, err := rows.Columns()
+	if err != nil {
+		return 0, err
+	}
+
+	m.rows = rows
+	m.columns = columns
+	dest := makeDest(m, len(columns))
+
+	slice := *m.dest
+	if len(slice) > 0 {
+		slice = slice[:0]
+	}
+
+	var n int
+
+	for rows.Next() {
+		m.m = make(map[string]interface{}, len(m.columns))
+
+		m.scanIndex = 0
+		if err := rows.Scan(dest...); err != nil {
+			return 0, err
+		}
+
+		slice = append(slice, m.m)
+		n++
+	}
+	if err := rows.Err(); err != nil {
+		return 0, err
+	}
+
+	*m.dest = slice
+	return n, nil
+}
+
+func (m *mapSliceModel) appendColumns(fmter schema.Formatter, b []byte) (_ []byte, err error) {
+	if err := m.initKeys(); err != nil {
+		return nil, err
+	}
+
+	for i, k := range m.keys {
+		if i > 0 {
+			b = append(b, ", "...)
+		}
+		b = fmter.AppendIdent(b, k)
+	}
+
+	return b, nil
+}
+
+func (m *mapSliceModel) appendValues(fmter schema.Formatter, b []byte) (_ []byte, err error) {
+	if err := m.initKeys(); err != nil {
+		return nil, err
+	}
+	slice := *m.dest
+
+	b = append(b, "VALUES "...)
+	if m.db.features.Has(feature.ValuesRow) {
+		b = append(b, "ROW("...)
+	} else {
+		b = append(b, '(')
+	}
+
+	if fmter.IsNop() {
+		for i := range m.keys {
+			if i > 0 {
+				b = append(b, ", "...)
+			}
+			b = append(b, '?')
+		}
+		return b, nil
+	}
+
+	for i, el := range slice {
+		if i > 0 {
+			b = append(b, "), "...)
+			if m.db.features.Has(feature.ValuesRow) {
+				b = append(b, "ROW("...)
+			} else {
+				b = append(b, '(')
+			}
+		}
+
+		for j, key := range m.keys {
+			if j > 0 {
+				b = append(b, ", "...)
+			}
+			b = fmter.Dialect().Append(fmter, b, el[key])
+		}
+	}
+
+	b = append(b, ')')
+
+	return b, nil
+}
+
+func (m *mapSliceModel) initKeys() error {
+	if m.keys != nil {
+		return nil
+	}
+
+	slice := *m.dest
+	if len(slice) == 0 {
+		return errors.New("bun: map slice is empty")
+	}
+
+	first := slice[0]
+	keys := make([]string, 0, len(first))
+
+	for k := range first {
+		keys = append(keys, k)
+	}
+
+	sort.Strings(keys)
+	m.keys = keys
+
+	return nil
+}