7405836411 Fix warning about deprecated method use (Dr Maxim Orlovsky)
f39b1300fa CI: do not fail fast (Dr Maxim Orlovsky)
f77c57195a Making Script method new_* names more consistent (Dr Maxim Orlovsky)
91b68a468d Taproot-related methods for Script type (Dr Maxim Orlovsky)
599c5f9488 Generalizing taproot key tweaking for KeyPairs (Dr Maxim Orlovsky)
Pull request description:
* Adds taproot-related methods to `Script`
* Fixes API for existing taproot methods
* Generalizes `TapTweak` trait to work with both public keys and key pairs
~~UPD: PR is pending https://github.com/rust-bitcoin/rust-secp256k1/pull/342~~
ACKs for top commit:
sanket1729:
ACK 7405836411
apoelstra:
ACK 7405836411
Tree-SHA512: 4a76dfffa1452baadc15e19812831ef9d2e66794c090a8fc123388d7119b2c8a1f0420ce723ad22e01683c8198711fe62e0cdf00c9ad2d2974606383baaf1cb0
9a8ab3f3ff Change type of final script witness to Witness from Vec<Vec<u8>> (sanket1729)
Pull request description:
Doing this would certainly help APIs downstream that operate on &Witness because they would not conversion from &Vec<Vec<u8>> to &Witness.
ACKs for top commit:
Kixunil:
ACK 9a8ab3f3ff
RCasatta:
ACK 9a8ab3f3ff
dr-orlovsky:
ACK 9a8ab3f3ff
apoelstra:
ACK 9a8ab3f3ff
Tree-SHA512: 647e18d254a51d6216a0122407146e8bc1d39504e76c1e0e746f740cec7cda587455b61d4cdadc3c59b1cf03eba87000de35fbde645a30fb166a84847ba101b2
a6e8f581db PSBT BIP32 keys moved to Secp256k1 from bitcoin ECDSA (Dr Maxim Orlovsky)
Pull request description:
Fourth step in implementation of Schnorr key support after #588. This PR is a follow-up to non-API breaking #589 and API-breaking #590, which must be reviewed and merged first. ~~(The current PR includes all commits from #589 and #590, which should be reviewed there. The only commit specific to this PR is b8105e95dc8651626b783403ca060f7d32d21144)~~
UPDATE: All related PRs are merged now and this PR is ready for the review
PR description:
While PSBT BIP174 does not specify whether uncompressed keys are supported in BIP32-related fields, from BIP32 it follows that it is impossible to use uncompressed keys within the extended keys. This PR fixes this situation and is a companion to BIP174 PR clarifying key serialization: https://github.com/bitcoin/bips/pull/1100
ACKs for top commit:
apoelstra:
ACK a6e8f581db
sanket1729:
ACK a6e8f581db. Not sure which order to merge since there are many ready PRs which that would break each other.
Tree-SHA512: 198ba646bbce1949b255a54a97957d952acdad8b7f9580be123116c0f44d773e6d90e0cac0d5993ec9a6b3328aa43aced0908522817861585877c50008fec835
I think it is more natural to write Wintess::new() followed by Witness::push()
then Witness::default(). In any case, there is no harm in having additional constructors.
Fourth step in implementation of Schnorr key support after #588.
While PSBT BIP174 does not specify whether uncompressed keys are supported in BIP32-related fields, from BIP32 it follows that it is impossible to use uncompressed keys within the extended keys. This PR fixes this situation and is a companion to BIP174 PR clarifying key serialization: https://github.com/bitcoin/bips/pull/1100
7f06e91a93 LowerHex and UpperHex implementations for LeafVersion (Dr Maxim Orlovsky)
6a3f3aabaf Inverse alternative formatting for LeafVersion type (Dr Maxim Orlovsky)
bec6694233 Fix docs on error conditions in LeafVersion::from_consensus (Dr Maxim Orlovsky)
7c28b47451 LowerHex and UpperHex implementations for FutureLeafVersion (Dr Maxim Orlovsky)
Pull request description:
Trivial post-merge fixups from review comments in #718
ACKs for top commit:
Kixunil:
ACK 7f06e91a93
sanket1729:
ACK 7f06e91a93
Tree-SHA512: d94c4bd3d0b466287c8965103f74ecaba185d14c13b6c3f37d9fbe194343b3fc902fd2c7716554ad01fe28ff89cda933df199b7e8388a3fa6097028caf62522b
cf0c48cc86 Improve Debug for PrivateKey (Dr Maxim Orlovsky)
b65a6ae49b Test for extended private key keypair generation f5875a (Dr Maxim Orlovsky)
e6a3d603c9 BIP32 extended key `to_ecdsa()` and `to_schnorr()` methods (Dr Maxim Orlovsky)
b72f56c4ae BIP32 extended keys are using Scep256k1 keys instead of bitcoin ECDSA (Dr Maxim Orlovsky)
Pull request description:
This is third step required to introduce Schnorr key support according to #588. This PR starts API-breaking changes and is follow-up to non-API breaking #589, which is already merged.
PR rationale: BIP32 does not support uncompressed keys and using type with compression flag was a mistake
ACKs for top commit:
apoelstra:
ACK cf0c48cc86
sanket1729:
ACK cf0c48cc86. #757 might need rework after this
Tree-SHA512: 6356a65004e7517256bacbf9aaeb69a22fd8536b341e567c5c4e819288e1105d083fe12ac0641404c407c97acf039bdc525f8e02b1b594a6cdda90106f3b1bdc
ef8a3a839e Introduce FutureLeafVersion (Dr Maxim Orlovsky)
b028385a72 Improve docs in LeafVersion (Dr Maxim Orlovsky)
839c022f29 Make serde for LeafVersion to have byte representation (Dr Maxim Orlovsky)
67b8db05a8 Converting LeafVersion into an enum (Dr Maxim Orlovsky)
2405417432 Use TAPROOT_ANNEX_PREFIX in sighash module (Dr Maxim Orlovsky)
Pull request description:
The original `LeafVersion` implementation was just a newtype around `u8`. I think that having enum explicitly listing consensus script implementation rules may be more beneficial in terms of both code readibility and future use of multiple script types, where `LeafVersion` may operate as a context object provided to `Script` to specify interpretation rules for particular op codes.
ACKs for top commit:
Kixunil:
ACK ef8a3a839e
sanket1729:
crACK ef8a3a839e. Waiting a day to let others complete review before merging.
apoelstra:
ACK ef8a3a839e
Tree-SHA512: 3356d2b9b00cf904edfece26d26ffbc646ba74446cc23ec4b2b4026ed50861285802f077226e30ba8fed466f68f8e8556c729ce48cb38581b1d95a02a6fde9cf
247a14f4c3 Use test big block for bench_stream_reader instead of making one (Riccardo Casatta)
b92dfbb63f exclude test_data when publishing the crate (Riccardo Casatta)
f5a9681a2a include a big block in test_data, use it for ser/de benchmark (Riccardo Casatta)
09dada55d6 Move bip158 test vectors to test_data (Riccardo Casatta)
06d1a820c3 Remove testnet block hex from tests, use test_data with include_bytes! (Riccardo Casatta)
Pull request description:
In the first two commits I moved some data from source files to the newly introduced `test_data` dir, including it with `include_[str|bytes]!` macro.
The second-to-last commit introduces a big block in test_data which is very handy in ser/de benchmark (I used it for #672) because with smaller blocks you may not notice performance improvements.
Since I don't want to pollute the package the last commit excludes the `test_data` dir from the published package. I think it's fine to do it because dependent packages don't run dependencies tests.
ACKs for top commit:
apoelstra:
ACK 247a14f4c3
Kixunil:
tACK 247a14f4c3
Tree-SHA512: a2beb635b0a358737d0b57d3e7205b1ddf87652b9a8c889ce63e2867659a8eaf7e43a5b87a453345d56d953745913f40b58596f449e5fbc87340e0dd2aef0727
533120899e Put rustdocs above attributes (Tobin Harding)
Pull request description:
(Trivial / Very low priority PR)
Rust idiomatic style is to put the rustdoc _above_ any attributes on types, functions, etc.
Audit the codebase and move comments/attributes to the correct place. Add a trailing full stop at times to neaten things up a little extra.
Done after discussion [here](https://github.com/rust-bitcoin/rust-secp256k1/pull/353#discussion_r778393138)
ACKs for top commit:
Kixunil:
ACK 533120899e
RCasatta:
ACK 533120899e
Tree-SHA512: 7cd00dc46de813cbe3f96417bb4b13980064e10110b421224496c8b64bbe87b61b6c757cc621fde1d05754be6ecdc08acdb51fd8978e3f820d2d93f7104062d1
e860333bf3 Fix typos (Riccardo Casatta)
9189539715 Use BufReader internally in StreamReader to avoid performance regression on existing callers (Riccardo Casatta)
5dfb93df71 Deprecate StreamReader (Riccardo Casatta)
9ca6c75b18 Bench StreamReader (Riccardo Casatta)
Pull request description:
`StreamReader` performance is extremely poor in case the object decoded is "big enough" for example a full Block.
In the common case, the buffer is 64k, so to successfully parse a 1MB block 16 decode attempts are made.
Even if a user increases the buffer size, `read` is not going to necessarily fill the buffer, as stated in the doc https://doc.rust-lang.org/stable/std/io/trait.Read.html#tymethod.read. In my tests, the reads are 64kB even with a 1MB buffer.
I think this is the root issue of the performance issue found in electrs in https://github.com/romanz/electrs/issues/547 and they now have decided to decode the TCP stream with their own code in cd0531b8b7 and 05e0221b8e.
Using directly `consensus_encode` seems to make more sense (taking care of using `BufRead` if necessary) so the `StreamReader` is deprecated
ACKs for top commit:
Kixunil:
ACK e860333bf3
apoelstra:
ACK e860333bf3
Tree-SHA512: a15a14f3f087be36271da5008d8dfb63866c9ddeb5ceb0e328b4a6d870131132a8b05103f7a3fed231f5bca099865efd07856b4766834d56ce2384b1bcdb889b
Rust idiomatic style is to put the rustdoc _above_ any attributes on
types, functions, etc.
Audit the codebase and move comments/attributes to the correct place.
Add a trailing full stop at times to neaten things up a little extra.
StreamReader before this commit is trying to repeatedly parse big object like
blocks at every read, causing useless overhead.
consensus_encode deal with partial data by simply blocking.
After this changes it doesn't look what remain of the StreamReader is really giving
value, so it's deprecated
7d982fa9a2 Add all tests from BIP 371 (sanket1729)
d22e0149ad Taproot psbt impl BIP 371 (sanket1729)
108fc3d4db Impl encodable traits for TapLeafhash (sanket1729)
c7478d8fd0 Derive serde for taproot stuctures (sanket1729)
Pull request description:
Built on top of #677 . Will rebase and mark ready for review after #677 is merged.
ACKs for top commit:
apoelstra:
ACK 7d982fa9a2
dr-orlovsky:
re-tACK 7d982fa9a2 basing on `git range-diff`. The original PR before last re-base was tested commit-by-commit.
Tree-SHA512: feb30e4b38d13110a9c0fabf6466d8f0fb7df09a82f4e01d70b8371b34ab0187004a6c63f9796c6585ee30841e8ee765ae9becae139d2e1e3d839553d64c3d1e
106acdc3ac Add fuzzing for Witness struct (Riccardo Casatta)
2fd0125bfa Introduce Witness struct mainly to improve ser/de performance while keeping most usability. (Riccardo Casatta)
Pull request description:
At the moment the Witness struct is `Vec<Vec<u8>>`, the vec inside a vec cause a lot of allocations, specifically:
- empty witness -> 1 allocation, while an empty vec doesn't allocate, the outer vec is not empty
- witness with n elements -> n+1 allocations
The proposed Witness struct contains the serialized format of the witness. This reduces the allocations to:
- empty witness -> 0 allocations
- witness with n elements -> 1 allocation for most common cases (you don't know how many bytes is long the entire witness beforehand, thus you need to estimate a good value, not too big to avoid wasting space and not too low to avoid vector reallocation, I used 128 since it covers about 80% of cases on mainnet)
The inconvenience is having slightly less comfortable access to the witness, but the iterator is efficient (no allocations) and you can always collect the iteration to have a Vec of slices. If you collect the iteration you end up doing allocation anyway, but the rationale is that it is an operation you need to do rarely while ser/de is done much more often.
I had to add a bigger block to better see the improvement (ae860247e191e2136d7c87382f78c96e0908d700), these are the results of the benches on my machine:
```
RCasatta/master_with_block
test blockdata::block::benches::bench_block_deserialize ... bench: 5,496,821 ns/iter (+/- 298,859)
test blockdata::block::benches::bench_block_serialize ... bench: 437,389 ns/iter (+/- 31,576)
test blockdata::block::benches::bench_block_serialize_logic ... bench: 108,759 ns/iter (+/- 5,807)
test blockdata::transaction::benches::bench_transaction_deserialize ... bench: 670 ns/iter (+/- 49)
test blockdata::transaction::benches::bench_transaction_get_size ... bench: 7 ns/iter (+/- 0)
test blockdata::transaction::benches::bench_transaction_serialize ... bench: 51 ns/iter (+/- 5)
test blockdata::transaction::benches::bench_transaction_serialize_logic ... bench: 13 ns/iter (+/- 0)
branch witness_with_block (this one)
test blockdata::block::benches::bench_block_deserialize ... bench: 4,302,788 ns/iter (+/- 424,806)
test blockdata::block::benches::bench_block_serialize ... bench: 366,493 ns/iter (+/- 42,216)
test blockdata::block::benches::bench_block_serialize_logic ... bench: 84,646 ns/iter (+/- 7,366)
test blockdata::transaction::benches::bench_transaction_deserialize ... bench: 648 ns/iter (+/- 77)
test blockdata::transaction::benches::bench_transaction_get_size ... bench: 7 ns/iter (+/- 0)
test blockdata::transaction::benches::bench_transaction_serialize ... bench: 50 ns/iter (+/- 5)
test blockdata::transaction::benches::bench_transaction_serialize_logic ... bench: 14 ns/iter (+/- 0)
```
With an increased performance to deserialize a block of about 21% and to serialize a block of about 16% (seems even higher than expected, need to do more tests to confirm, I'll appreciate tests results from reviewers)
ACKs for top commit:
apoelstra:
ACK 106acdc3ac
sanket1729:
ACK 106acdc3ac
dr-orlovsky:
utACK 106acdc3ac
Tree-SHA512: e4f23bdd55075c7ea788bc55846fd9e30f9cb76d5847cb259bddbf72523857715b0d4dbac505be3dfb9d4b1bcae289384ab39885b4887e188f8f1c06caf4049a
2959e04ebd Allow specifing a raw `TapLeafHash` in sighash computation (Alekos Filini)
Pull request description:
Still need to add some tests but the code should be ready for review. Please let me know if you have better ideas for the enum naming.
---
Instead of always requiring the full raw script and leaf version, allow
just specifying a raw leaf hash to the sighash computation functions.
This is very useful when dealing with PSBTs, because the
`PSBT_IN_TAP_BIP32_DERIVATION` field only maps a public key to a leaf
hash, so a signer could just take it and produce a signature with it
rathern than having to jump through hoops to recover the full raw
script.
ACKs for top commit:
sanket1729:
Tested locally. ACK 2959e04. Reviewed range-diff with 5aa1d02
apoelstra:
ACK 2959e04ebd
Tree-SHA512: 830be0b8382ac59b73e6481f61ec1effdcd32859c04382e6cd5a43ac689d6e528f9a8b27c026ee81f5d5b59d2e3c397f9c271145e001ff2dc4815764fc21a2c6
Witness struct is in place of the Vec<Vec<u8>> we have before this commit.
from_vec() and to_vec() methods are provided to switch between this type and Vec<Vec<u8>>
Moreover, implementation of Default, Iterator and others allows to have similar behaviour but
using a single Vec prevent many allocations during deserialization which in turns results in
better performance, even 20% better perfomance on recent block.
last() and second_to_last() allows to access respective element without going through costly Vec
transformation
826fed53f2 transactions: add a note about `get_vsize` and standardness rules (Antoine Poinsot)
Pull request description:
If they ever hit a discrepancy they must really be doing something dodgy but hey :)
ACKs for top commit:
dr-orlovsky:
ACK 826fed53f2
Tree-SHA512: c618a80b047797625a233939d2c1146e8b4ce44215648841813f78178577afc844f5e561e4e60b4084e315735894ecb354af8d81f4702f5354e5d5cd05b52ac4
Instead of always requiring the full raw script and leaf version, allow
just specifying a raw leaf hash to the sighash computation functions.
This is very useful when dealing with PSBTs, because the
`PSBT_IN_TAP_BIP32_DERIVATION` field only maps a public key to a leaf
hash, so a signer could just take it and produce a signature with it
rathern than having to jump through hoops to recover the full raw
script.
f690b8e362 Be more liberal when parsing Denomination (Tobin Harding)
628168e493 Add missing white space character (Tobin Harding)
Pull request description:
There is no reason to force users to use a particular format or case for `Denomination` strings. Users may wish to write any of the following and all seem reasonable
- 100 sats
- 100 sat
- 100 SAT
The same goes for various other `Denomination`s.
- Patch 1 enables usage of "sats", "sat", "bit", "bits"
- Patch 2 enables usage of various lower/uper case formatting
Fixes: #729
ACKs for top commit:
Kixunil:
ACK f690b8e362
apoelstra:
ACK f690b8e362
Tree-SHA512: a785608e19a7ba6f689dc022cb17a709041ff56abeaa74649d0832a8bd8aac4593c7a79b46a47dd417796c588d669f50fb3c8b8a984be332ca38a1fef2dcd4ce
Using the latest version of rust-bitcoin master on rust-miniscript
errors on bitcoin::SigHashType not found. In the original PR, I only
renamed the export to ECDSASigHashType, but original re-export should
also be there in lib.rs to avoid to breaking changes downstream.
779d4110c6 Fixed a bunch of clippy lints, added clippy.toml (Martin Habovstiak)
Pull request description:
This is the initial step towards using and maybe enforcing clippy.
It does not fix all lints as some are not applicable. They may be
explicitly ignored later.
Some discussion about clippy was in #685
ACKs for top commit:
apoelstra:
ACK 779d4110c6
RCasatta:
ACK 779d4110c6
Tree-SHA512: fb9192c77565a0b1b2118877c6413945d65900e4e95b3741107bf6cddef1fa65ff09fc5b7814de421382292321cca6bd860bf17b73a227d193a0a13758ee25eb
7aacc3782a Add tests from BIP341 (sanket1729)
61629cc733 Make taproot hashes forward display (sanket1729)
Pull request description:
Add tests for taproot.
- ~Also fixes one bug in #677, namely, I was returning `LeafVersion::default()` instead of given version~
- ~ Fixes a bug in #691 about taking secp context as a reference instead of consuming it. This should have not passed my review, but this is easy to miss. ~
- Makes the display on taproot hashes forward instead of the reverse (because the BIP prints in a forward way, I think we should too and it is more natural. )
ACKs for top commit:
RCasatta:
ACK 7aacc3782a
apoelstra:
ACK 7aacc3782a
Tree-SHA512: 2e0442131fc036ffa10f88c91c8fc02d9b67ff6c16c592aa6f4e6a220c26a00fc6ca95a288f14aa40667a289fb0446219fd6c76c0196ead766252356592b9941
There is no reason to force users to use one particular form when
providing a denomination string. We can be liberal in what we accept
with no loss of clarity.
Allow `Denomination` strings to use a variety of forms, in particular
lower case and uppercase.
Note, we explicitly disallow various forms of `Msat` because it is
ambiguous whether this means milli or mega sats.
Co-developed-by: Martin Habovštiak <martin.habovstiak@gmail.com>
This is the initial step towards using and maybe enforcing clippy.
It does not fix all lints as some are not applicable. They may be
explicitly ignored later.
b454cf8e15 Return None from merkle_root functions (Tobin Harding)
7a8b017ea3 Use correct spelling of merkle (Tobin Harding)
Pull request description:
~Do two minor refactorings to the `bitcoin_merkle_root[_inline] functions.~
This PR has grown, is no longer a refactoring because the two functions have been changed to return an `Option`.
First patch is cleanup. Here is the commit message for the second patch
```
The merkle_root of an empty tree is undefined, this is the only error
case we have for the two `bitcoin_merkle_root*` functions. We can fully
describe this error case by returning an `Option` if args are found to
be empty.
While we are at it, refactor out a recursive helper function to make
reading the code between the two functions easier.
```
ACKs for top commit:
Kixunil:
ACK b454cf8e15
dr-orlovsky:
ACK b454cf8e15
Tree-SHA512: 961714a8b0eb0dad493a1548317d875d64ca22d2d584c905c502369b5f6e5a9f8be1edd7345136b44964dc0bde7a4c43bfaff4287d1dbf7fd736da79818074e3
8361129518 Add SchnorrSig type (sanket1729)
94cfe79170 Rename existing SigHashType to EcdsaSigHashType (sanket1729)
648b3975a5 Add SchnorrSigHashType::from_u8 (sanket1729)
410e8bf46c Rename sighash::SigHashType::SigHashType to SchnorrSigHashType (sanket1729)
fa112a793a Add EcdsaSig (sanket1729)
Pull request description:
Fixes#670 . Separates `SchnorrSigHashType` and `LegacySigHashType`. Also adds the following new structs:
```rust
pub struct SchnorrSig {
/// The underlying schnorr signature
pub sig: secp256k1::schnorrsig::Signature,
/// The corresponding hash type
pub hash_ty: SchnorrSigHashType,
}
pub struct EcdsaSig {
/// The underlying DER serialized Signature
pub sig: secp256k1::Signature,
/// The corresponding hash type
pub hash_ty: LegacySigHashType,
}
```
This code is currently minimal to aid reviews. We can at a later point implement (Encodeable, psbt::Serialize, FromHex, ToHex) etc in follow-up PRs.
ACKs for top commit:
Kixunil:
ACK 8361129518
RCasatta:
ACK 8361129518
Tree-SHA512: 800ddcb3677a4f19e9d1c2a7eb7e95b0a677e9135e1e99f9e42956fc6a3fc94f639403076b4925b3adba6fdd95f56a99c2e47d0310675ad51ce5e7453c7355b6
506e03fa4d util/address: use hash functions of PublicKey/Script (Marko Bencun)
f826316c25 util/address: avoid .expect/panic (Marko Bencun)
ad83f6ae00 util/address: make address encoding more modular (Marko Bencun)
Pull request description:
This allow library clients to plug their own encoding parameters in a
backwards compatible manner.
Top commit has no ACKs.
Tree-SHA512: ae2ececbdfe4984fd62c975f4956686d79f6f5a6e65c34b55daa76fe785b8483ed7f35208d36b8bee545c7edd39ac878277a0fb8ea8c64a1943081e15c818bff
b5bf6d7319 Improve rustdocs on schnorr module (Tobin Harding)
a6d3514f2b Return parity when doing tap_tweak (Tobin Harding)
7af0999745 Re-name TweakedPublicKey constructor (Tobin Harding)
3c3cf0396b Remove use of unreachable in error branch (Tobin Harding)
d8e42d153e Remove 'what' comments (Tobin Harding)
b60db79a3b Use un/tweaked public key types (Tobin Harding)
402bd993b2 Add standard derives to TweakedPublickKey (Tobin Harding)
9c015d9ce3 Add newline to end of file (Tobin Harding)
Pull request description:
We have two types for tweaked/untweaked schnorr public keys to help users of the taproot API not mix these two keys up. Currently the `taproot` module uses 'raw' `schnoor::PublicKey`s.
Use the `schnoor` module's tweak/untweaked public key types for the `taproot` API.
Fixes: #725
Please note, I saw this was labeled 'good-first-issue' but I ignored that and greedily implemented a solution because of two reasons
1. We want to get taproot stuff done post haste.
2. I'm struggling to follow what is going on with all the taproot work so this seemed like a way to get my hands dirty.
ACKs for top commit:
dr-orlovsky:
utACK b5bf6d7319
sanket1729:
ACK b5bf6d7319
Tree-SHA512: e3e0480e0d193877c33ac11d0e3a288b0393d9475b26056914e439cb3f19583c1936e70d048df8d2120a36a63b6b592d12e21ca3ab7e058dce6f8f873c3b598b
1518517374 Decrease Huffman weight type to 32 bits (Jeremy Rubin)
Pull request description:
This builds on https://github.com/rust-bitcoin/rust-bitcoin/pull/699 but is the more bikesheddable part since it changes the API.
> u32 of weight should be enough for any branch.
-- Bill Gates
ACKs for top commit:
dr-orlovsky:
utACK 1518517374
Kixunil:
ACK 1518517374
Tree-SHA512: 9c507ae6129dda8dc069b0a142181a78cf89cb3ebf9d2169c46662822cb4ea9ed075bf484528f5399fe0ed383a425174a702e2d685f31c246f5a86c46ed17c3a
Currently we calculate the parity during `tap_tweak` but do not return
it, this means others must re-do work done inside `tap_tweak` in order
to calculate the parity. We can just return the parity along with the
tweaked key.
Keeping inline with the method on `UntweakedPublicKey` that outputs a
`TweakedPublicKey` we can use the same name, for the same reasons.
Use `dangerous_assume_tweaked` as the constructor name to highlight the
fact that this constructor should probably not be being used.