dcr: Add send all.

[JoeGruffins]

No description provided.

[itswisdomagain]

Untested, but LGTM.

[JoeGruffins]

Both of these should be per byte I think, changed https://github.com/decred/libwallet/compare/8b3c43115468c4d8ec3f3d701696d3eb5deef5fc..bf70ab203d9352826f02fc5b5f2310581d803e94

[jrick]

does this respect the maximum tx size, or even the mempool policy for max accepted tx size it will relay?

[jrick]

Also, why not use Wallet.NewUnsignedTransaction with wallet.OutputSelectionAlgorithmAll?

[JoeGruffins]

Also, why not use Wallet.NewUnsignedTransaction with wallet.OutputSelectionAlgorithmAll?

I wasn't sure how to deal with the fee in this case. We want to send all and not leave anything, so would we need to calculate the fee when using Wallet.NewUnsignedTransaction in order to get the correct amount to send and then that amount would have to agree with wallet internal fee calculations?

[JoeGruffins]

Just rebased.

[JoeGruffins]

Respecting max tx size, I think https://github.com/decred/libwallet/compare/3dd5a92659ffd25c14a78de2f4ed574d0624d5a5..533ca6d0995f30e04c6620336f727b7414277e3f

[jrick]

Also, why not use Wallet.NewUnsignedTransaction with wallet.OutputSelectionAlgorithmAll?

I wasn't sure how to deal with the fee in this case. We want to send all and not leave anything, so would we need to calculate the fee when using Wallet.NewUnsignedTransaction in order to get the correct amount to send and then that amount would have to agree with wallet internal fee calculations?

The method takes a fee rate (per kB), not an absolute fee. No matter what fee rate you provide, it shouldn't change the input selection, only the amount that is eventually sent.

[JoeGruffins]

Ok, do we just set the output value to max value? I'll try.

[JoeGruffins]

The wallet method hangs when setting the output value to the max int64. May be something to do with cgo, unsure.

wallet.OutputSelectionAlgorithmAll I assume uses all the inputs, but we still have to calculate the fee in order to know what the output value should be, or am I still missing something? If we are calculating the fee anyway ourselves and already know all inputs I don't know why it is important to pass the values through wallet. Am I missing more checks? We are checking utxo.Spendable already.

[JoeGruffins]

Is the "OutputSelectionAlgorithm" argument completely ignored if we include an input source? It's convenient for use to choose the inputs because in cake users can choose to "freeze" or use certain inputs. Perhaps it is more correct for us to lock and unlock inputs in wallet? That would require alot of changes presently that I would rather not make at this time. I don't think the OutputSelectionAlgorithm argument is great for us atm.

Maybe I am still missing something though.

[jrick]

Input source must be nil to use OutputSelectionAlgorithmAll.

If you want to sweep all value, you need to provide only a change address source and no other outputs. This will result in paying the total input value, minus any fee, to the single change address.

[jrick]

If you want to control which inputs are used, return them all from the first call to the input source you provide, and again, specify only a change address source and no other outputs. This should have the same effect as OutputSelectionAlgorithmAll but lets you select which outputs are used.

[JoeGruffins]

Thank you for the change source advice, that is working. https://github.com/decred/libwallet/compare/533ca6d0995f30e04c6620336f727b7414277e3f..fd79c8ee74c8db29c284116795c65afc96624857