Adds fix for edge-cases involving small UTXOs (where value < fee) where the coin_select calculation would panic with overflow/underflow errors.
Bitcoin is limited to 21*(10^6), so any Bitcoin amount fits into i64.
To allow adding UTXOs external to the current wallet.
The caller must provide the psbt::Input so we can create a coherent PSBT
at the end and so this is compatible with existing PSBT workflows.
Main changes:
- There are now two types of UTXOs, local and foreign reflected in a
`Utxo` enum.
- `WeightedUtxo` now captures floating `(Utxo, usize)` tuples
- `CoinSelectionResult` now has methods on it for distinguishing between
local amount included vs total.
Currently we have a unit test to test that signers are sorted by
ordering. We call `add_external` to add them but currently we add them
in the same order we expect them to be in. This means if the
implementation happens to insert them simply in the order they are
added (i.e. insert to end of list) then this test will still pass.
Insert in a mixed order, including one lower followed by one higher -
this ensures we are not inserting at the front or at the back but are
actually sorting based on the `SignerOrdering`.
If we give the `DummySigner` a valid identifier then we can use this to
do comparison.
Half the time we do comparison we only have a `dyn Signer` so we cannot
use `PartialEq`, add a helper function to check equality (this is in
test code so its not toooo ugly).
Thanks @afilini for the suggestion.
Clippy emits error:
comparing trait object pointers compares a non-unique vtable address
The vtable is an implementation detail, it may change in future. we
should not be comparing vtable addresses for equality. Instead we can
get a pointer to the data field of a fat pointer and compare on that.
The `ChunksIterator` constructor is only used when either `electrum` or
`esplora` features are enabled. Conditionally build it so that we do not
get a clippy warning when building without these features.
Clippy emits warning:
warning: field assignment outside of initializer for an instance
created with Default::default()
Do as suggested by clippy and use the default init pattern.
```
let foo = Foo {
bar: ...,
Default::default()
}
```
As suggested by clippy we can use `.next()` on an iterator instead of
`nth(0)`. Although arguably no clearer, and certainly no worse, it keeps
clippy quiet and a clean lint is a good thing.
Clippy emits warning:
warning: avoid using `collect()` when not needed
As suggested by clippy just use `count` directly on the iterator instead
of `collect` followed by `len`.
Due to brain malfunction I made utxos into a BTree. This made a test
pass but is incorrect. The test itself was incorrect as per comment in
https://github.com/bitcoindevkit/bdk/pull/258#issuecomment-758370380
So I (1) reverted utxos back to a Vec, (2) fixed the test and expanded
the comment in the test.