This adds testing of the `futures` feature to CI. In order to avoid
introducing a dependency on `std`, we switch to using the `futures-util`
crate directly enabling only a subset of features. To this end, we also
switch to using the `select_biased!` macro, which is equivalent to
`select!` except that it doesn't choose ready futures pseudo-randomly
at runtime.
Rust is incredibly forgiving in attempts to access `std`, making it
rather difficult to test `no-std` properly. In practice, the only
decent way to do so is to actually build for a platform that does
not have `std`, which we do here by building the `no-std-check`
crate for `arm-thumbv7m-none-eabi`.
So far, CI did not check the code in the `release` build profile, which
could result in some things not getting caught. To fix this, we now
implement a new CI job that runs checks in the `release` profile.
Switch to stable toolchain.
1.51 (and other earlier versions of `rustc`) appear to refuse to
accept our documentation links due to a bogus failure to resolve
`ChannelTypeFeatures::supports_scid_privacy`.
To ensure no-std is honored across dependencies, add a crate depending
on lightning crates supporting no-std. This should ensure any
regressions are caught. Otherwise, cargo doesn't seem to catch some
incompatibilities (e.g., f64::log10 unavailable in core) and seemingly
across other dependencies as describe here:
https://blog.dbrgn.ch/2019/12/24/testing-for-no-std-compatibility/
1.41.1 is currently the Firefox ESR MSRV, which means its also the
version several Linux distros ship. Further, rust-bitcoin is likely
to make a similar change soon, see
https://github.com/rust-bitcoin/rust-bitcoin/issues/510.
`cargo bench` sets `cfg(test)`, causing us to hit some test-only
code in the router when benchmarking, throwing off our benchmarks
substantially. Here we swap from the `unstable` feature to a more
clearly internal feature (`_bench_unstable`) and also checking for
it when enabling test-only code.
Some time ago codecov stopped supporting their old v1 uploader, and
it seems they've now finally turned it off, so we aren't getting
any coverage reports anymore. Hopefully upgrading is pretty trivial.
This adds a new (non-feature) cfg argument `c_bindings` which will
be set when building C bindings. With this, we can (slightly) tweak
behavior and API based on whether we are being built for Rust or C
users.
Ideally we'd never need this, but as long as we can keep the API
consistent-enough to avoid material code drift, this gives us a
cheap way of doing the "right" thing for both C and Rust when the
two are in tension.
We also move lightning-background-processor to support the same
MSRV as the main lightning crate, instead of only
lightning-net-tokio's MSRV.
