In preparation for releasing `io v0.2.0` bump the version number,
add a changelog entry, update the lock files, and depend on the new
version in all crates that depend on `io`.
In preparation for releasing `internals v0.4.0` bump the version number,
add a changelog entry, update the lock files, and depend on the new
version in all crates that depend on `internals`.
Conditional compilation depending on Rust version using `cfg` had the
disadvantage that we had to write the same code multiple times, compile
it multiple times, execute it multiple times, update it multiple
times... Apart from obvious maintenance issues the build script wasn't
generating the list of allowed `cfg`s so those had to be maintained
manually in `Cargo.toml`. This was fixable by printing an appropriate
line but it's best to do it together with the other changes.
Because we cannot export `cfg` flags from a crate to different crates we
take a completely different approach: we define a macro called
`rust_version` that takes a very naturally looking condition such as
`if >= 1.70 {}`. This macro is auto-generated so that it produces
different results based on the compiler version - it either expands to
first block or the second block (after `else`).
This way, the other crates can simply call the macro when needed.
Unfortunately some minimal maintenance is still needed: to update the
max version number when a newer version is used. (Note that code will
still work with higher versions, it only limits which conditions can be
used in downstream code.) This can be automated with the pin update
script or we could just put the pin file into the `internals` directory
and read the value from there. Not automating isn't terrible either
since anyone adding a cfg with higher version will see a nice error
about unknown version of Rust and can update it manually.
Because this changes syntax to a more naturally looking version number,
as a side effect the `cond_const` macro could be also updated to use the
new macro under the hood, providing much nicer experience - it is no
longer needed to provide human-readable version of the version string to
put in the note about `const`ness requiring a newer version. As such the
note is now always there using a single source of truth.
It's also a great moment to introduce this change right now since
there's currently no conditional compilation used in `bitcoin` crate
making the changes minimal.
Previously we've only implemented `bitcoin-io` traits for `BufReader`
and `BufWriter` with the reasoning that people should most likely use
those and implementing for other types is too much work. However since
then there were requests to implement them so we do in this commit.
We want to implement the traits for more types which would be tedious
without a macro and it'd risk forgetting to forward some method since
they may be speialized. This also adds previously-forgotten
specializations. It also relaxes the implicit `Sized` bound on
`BufReader` and `BufWriter` in Rust versions above 1.72.
The version 1.63 satisfies our requirements for MSRV and provides
significant benefits so this commit bumps it. This commit also starts
using some advantages of the new MSRV, namely namespaced features, weak
dependencies and the ability to use trait bounds in `const` context.
This however does not yet migrade the `rand-std` feature because that
requires a release of `secp256k1` with the same kind of change - bumping
MSRV to 1.63 and removing `rand-std` in favor of weak dependency.
There have only been two PRs merged that touched the `io` crate since it
as last released. The changes are additive so we can do a pre-0.1 point
release.
In preparation for release bump the version and add a changelog entry.
We attempted to release with the current 0.1.0 version forgetting that
we had previously released an empty crate with that version to reserve
the name on crates.io.
Bump the version to 0.1.1 and release the actual code.
In order to support standard (de)serialization of structs, the
`rust-bitcoin` ecosystem uses the standard `std::io::{Read,Write}`
traits. This works great for environments with `std`, however sadly
the `std::io` module has not yet been added to the `core` crate.
Thus, in `no-std`, the `rust-bitcoin` ecosystem has historically
used the `core2` crate to provide copies of the `std::io` module
without any major dependencies. Sadly, its one dependency,
`memchr`, recently broke our MSRV.
Worse, because we didn't want to take on any excess dependencies
for `std` builds, `rust-bitcoin` has had to have
mutually-exclusive `std` and `no-std` builds. This breaks general
assumptions about how features work in Rust, causing substantial
pain for applications far downstream of `rust-bitcoin` crates.
Here, we add a new `bitcoin_io` crate, making it an unconditional
dependency and using its `io` module in the in-repository crates
in place of `std::io` and `core2::io`. As it is not substantial
additional code, the `hashes` io implementations are no longer
feature-gated.
This doesn't actually accomplish anything on its own, only adding
the new crate which still depends on `core2`.
Tobin C. Harding
Martin Habovstiak
Andrew Poelstra
Matt Corallo