Method transition

src/transactions.ts:149–166

* Transition the transaction in the state machine * @param nextState - The new state to transition to

(nextState: TxnState)

   * @param nextState - The new state to transition to
   */
  transition(nextState: TxnState): void {
    const nextStates = stateMachine[this.state];
    if (nextStates && nextStates.includes(nextState)) {
      this.state = nextState;
      if (
        this.state === TxnState.NO_TRANSACTION ||
        this.state === TxnState.STARTING_TRANSACTION ||
        this.state === TxnState.TRANSACTION_ABORTED
      ) {
        this.unpinServer();
      }
      return;
    }

    throw new MongoRuntimeError(
      `Attempted illegal state transition from [${this.state}] to [${nextState}]`
    );
  }

  pinServer(server: Server): void {
    if (this.isActive) {