* Remove unused mempool storage errors
Preparation for ticket #2819.
Removing these errors means that we don't have to decide
which type of transaction ID match we want for them.
* Remove unused mempool errors, and deduplicate storage errors
* rustfmt
* Add `Transaction::spent_outpoints` getter method
Returns an iterator over the UTXO `OutPoint`s spent by the transaction.
* Add `mempool::Error::Conflict` variant
An error representing that a transaction was rejected because it
conflicts with another transaction that's already in the mempool.
* Reject conflicting mempool transactions
Reject including a transaction in the mempool if it spends outputs
already spent by, or reveals nullifiers already revealed by another
transaction in the mempool.
* Fix typo in documentation
Remove the `r` that was incorrectly added.
Co-authored-by: teor <teor@riseup.net>
* Specify that the conflict is a spend conflict
Make the situation clearer, because there are other types of conflict.
Co-authored-by: teor <teor@riseup.net>
* Clarify that the outpoints are from inputs
Because otherwise it could lead to confusion because it could also mean
the outputs of the transaction represented as `OutPoint` references.
Co-authored-by: teor <teor@riseup.net>
* Create `storage::tests::vectors` module
Refactor to follow the convention used for other tests.
* Add an `AtLeastOne::first_mut` method
A getter to allow changing the first element.
* Add an `AtLeastOne::push` method
Allow appending elements to the collection.
* Derive `Arbitrary` for `FieldNotPresent`
This is just to make the code that generates arbitrary anchors a bit
simpler.
* Test if conflicting transactions are rejected
Generate two transactions (either V4 or V5) and insert a conflicting
spend, which can be either a transparent UTXO, or a nullifier for one of
the shielded pools. Check that any attempt to insert both transactions
causes one to be accepted and the other to be rejected.
* Delete a TODO comment that we decided not to do
Co-authored-by: teor <teor@riseup.net>