Following one transaction from the mempool into a block and back out again.
Following one transaction from the mempool into a block and back out again.
Declared separately from Transaction because it is a different question. A provider that observes only the sources it was asked to watch can serve transaction subscriptions — it matches what it fetched — while having no way to answer "what happened to this particular hash", because a transaction it was never asked about is a transaction it never looked up. Left undeclared, such a provider reports Pending forever for a transaction that is confirmed on chain, which is worse than refusing: the subscriber has no way to tell a transaction that has not landed from one the provider never watched.