{{/*
Copyright 2019-present Facebook Inc. All rights reserved.
This source code is licensed under the Apache 2.0 license found
in the LICENSE file in the root directory of this source tree.
*/}}

{{/* custom errors and errors handlers for sql dialects */}}
{{ define "dialect/sql/errors" }}
func isSQLConstraintError(err error) (*ErrConstraintFailed, bool) {
	var (
		msg = err.Error()
		// error format per dialect.
		errors = [...]string{
			"Error 1062",										// MySQL 1062 error (ER_DUP_ENTRY).
			"UNIQUE constraint failed",							// SQLite.
			"duplicate key value violates unique constraint",	// PostgreSQL.
		}
	)
	for i := range errors {
		if strings.Contains(msg, errors[i]) {
			return &ErrConstraintFailed{msg, err}, true
		}
	}
	return nil, false
}

// rollback calls to tx.Rollback and wraps the given error with the rollback error if occurred.
func rollback(tx dialect.Tx, err error) error {
	if rerr := tx.Rollback(); rerr != nil {
		err = fmt.Errorf("%s: %v", err.Error(), rerr)
	}
	if err, ok := isSQLConstraintError(err); ok {
		return err
	}
	return err
}
{{ end }}