Whether or not every file needs an explicit license comment is out of
scope for this patch; in the `bitcoin` crate we use SPDX identifiers
because they are a single line with no loss of "benefit" over any longer
form.
Use SPDX identifiers in `hashes`. Drop the mention of re-licensing code
from Apache to CC0-1 (because the original code was written by Andrew
as well as the copied code then if the argument ever comes up it can be
easily countered).
We have old Rust 1.29 error handling code still in `hashes`. Implement
`std::error::Error` for the `hex::Error` and `error::Error` types in
line with "modern" Rust 1.41.1 error handling.
We would like to bring the `bitcoin_hashes` crate into the
`rust-bitcoin` repository.
Import `bitcoin_hashes` into `rust-bitocin/hashes`, doing so looses all
the commit history from the original crate but if we archive the
original repository then the history will be preserved. We maintain the
same version number obviously and in the changelog we note the change of
repository.
Commit hash that was tip of `bitcoin_hashes` at time of import:
commit 54c16249e06cc6b7870c7fc07d90f489d82647c7
Includes making `embedded` and `fuzzing` per-crate i.e., move them into
`bitcoin` as hashes includes these also.
NOTE: Does _not_ enable fuzzing for `hashes` in CI.
Notes on CI:
Attempts to merge in the github actions from the hashes crate however reduces
coverage by not running hashes tests for beta toolchain. Some additional
work could be done to improve the CI to increase efficiency without
reducing coverage. Leaving for another day.
Tobin C. Harding