Make generate_and_send_coins send rewards to bech32 address.

[jachiang]

Default generate() call sends rewards to P2SH(P2WPKH) output. Sending rewards to a native segwit address reduces weight of spending transaction and facilitates weight comparisons between native segwit v0 and v1 transactions. I would prefer minimizing transaction weights where possible.

[jnewbery]

I'm confused about the rationale here. Presumably we'd been making weight comparisons between transactions we create ourselves (see https://github.com/bitcoinops/taproot-workshop/pull/129 for example)

[jachiang]

Sorry, the rational isn't correct.

In the chapter 2.2 update (#133) , I compare two transactions.

• 1) TX created with createrawtransaction with a OP_RETURN output (with a contract commitment).
• 2) TX generated with generate_and_send_coins to send to a segwit v1 output (pay-to-contract commitment)

For the weight comparison, I prefer (it isn't necessary) to minimize the weight of both transactions, by spending native segwit coinbase outputs in both cases.

[jnewbery]

for (ii), how are you adding the commitment to the transaction output if you're creating the tx with generate_and_send_coins()?

[jachiang]

for (ii), how are you adding the commitment to the transaction output if you're creating the tx with generate_and_send_coins()?

With a tweaked pubkey which is encoded in the segwit v1 address passed to generate_and_send_coins(segwit_v1_address).

[jachiang]

Hi @jnewbery - anything I can do to move this forward if desirable?

[jnewbery]

Sorry for the delay here. Using bech32 everywhere seems reasonable to me. Thanks!