accounts/abi/bind/backends: add TransactionByHash to SimulatedBackend (#19026)

accounts/abi/bind/backends/simulated.go

@@ -164,6 +164,25 @@ func (b *SimulatedBackend) TransactionReceipt(ctx context.Context, txHash common
 	return receipt, nil
 }
 
+// TransactionByHash checks the pool of pending transactions in addition to the
+// blockchain. The isPending return value indicates whether the transaction has been
+// mined yet. Note that the transaction may not be part of the canonical chain even if
+// it's not pending.
+func (b *SimulatedBackend) TransactionByHash(ctx context.Context, txHash common.Hash) (tx *types.Transaction, isPending bool, err error) {
+
+	tx = b.pendingBlock.Transaction(txHash)
+	if tx != nil {
+		return tx, true, nil
+	}
+
+	tx, _, _, _ = rawdb.ReadTransaction(b.database, txHash)
+	if tx != nil {
+		return tx, false, nil
+	}
+
+	return nil, false, ethereum.NotFound
+}
+
 // PendingCodeAt returns the code associated with an account in the pending state.
 func (b *SimulatedBackend) PendingCodeAt(ctx context.Context, contract common.Address) ([]byte, error) {
 	b.mu.Lock()