This macro is pretty weird -- it requires that a freestanding
`from_engine` method exists, which it uses to implement a `from_engine`
method within an impl block, by just calling through to the freestanding
method.
To reduce indirection, at a very small cost in increased repeated code
(we now need to add a `impl Hash {` and `}` and doccomment around each
freestanding function, we just remove this from the macro entirely.
This will allow us to implement `from_engine` for `sha256t::Hash` in a
different way than for the non-generic hash types.
To minimize the diff, we do not re-indent the freestanding
`from_engine`. We will do that in the next commit. However, the diff is
still a bit noisy because I had to replace `fn from_engine` with `pub fn
from_engine` in every case. I took the opportunity to also change the
return type from `Hash` to `Self` to make it clearer that these are
constructors.
We would like to do away with the `GeneralHash` trait. Currently we
bound `Hmac` and `HmacEngine` on it but this is unnecessary now that we
have added `HashEngine::finalize` and `HashEngine::Hash`.
Bound the `HmacEngine` on `HashEngine` (which has an associated `Hash`
type returned by `finilalize`).
Bound `Hmac` type on `T::Hash` where `T` is `HashEngine`.
Includes some minor shortening of local variable names around hmac
engine usage.
Note this means that `Hmac` no longer implements `GeneralHash`.
Add an associated const `Hash` to the `HashEngine` trait. Also add a
`finalize` method that converts the engine to the associated hash.
For now just use the existent `from_engine` stuff. We can refactor
later.
This function is deprecated, stop using it in favour of
`Hash::from_byte_array`.
Patch only touches test code, I'm guessing that is why lint warnings
were no showing up.
In preparation for removing a bunch of macros move all the modules to
`<mod>/mod.rs`.
Do so by running the following shell:
```bash
for mod in hash160 ripemd160 sha1 sha256 sha256d sha256t \
sha384 sha512 sha512_256 siphash24 hkdf hmac; do
mkdir $mod
mv "$mod.rs" "$mod/mod.rs"
done
```
Internal change only.
Andrew Poelstra
Tobin C. Harding
Jamil Lambert, PhD