fix(bug): runMigrations not using named returned properly (#5913)

* return nil when no transaction is opened

* use named return for retErr

* add a comment

internal/db/schema/internal/postgres/postgres.go

@@ -208,8 +208,11 @@ func (p *Postgres) RollbackRun(ctx context.Context) error {
 	defer func() {
 		p.tx = nil
 	}()
+
+	// p.tx is set to nil after the commit so if p.tx == nil, we assume that the transaction has
+	// already been committed and do nothing
 	if p.tx == nil {
-		return errors.New(ctx, errors.MigrationIntegrity, op, "no pending transaction")
+		return nil
 	}
 	if err := p.tx.Rollback(); err != nil {
 		if errors.Is(err, sql.ErrTxDone) {

internal/db/schema/manager.go

@@ -243,12 +243,9 @@ func (b *Manager) ApplyMigrations(ctx context.Context) ([]RepairLog, error) {
 // runMigrations passes migration queries to a database driver and manages
 // the version and dirty bit. Cancellation or deadline/timeout is managed
 // through the passed in context.
-func (b *Manager) runMigrations(ctx context.Context, p *provider.Provider) ([]RepairLog, error) {
+func (b *Manager) runMigrations(ctx context.Context, p *provider.Provider) (logEntries []RepairLog, retErr error) {
 	const op = "schema.(Manager).runMigrations"
 
-	var logEntries []RepairLog
-	var retErr error
-
 	if startErr := b.driver.StartRun(ctx); startErr != nil {
 		return nil, errors.Wrap(ctx, startErr, op)
 	}
@@ -312,5 +309,5 @@ func (b *Manager) runMigrations(ctx context.Context, p *provider.Provider) ([]Re
 		return nil, errors.Wrap(ctx, err, op)
 	}
 
-	return logEntries, retErr
+	return logEntries, nil
 }