Provide an ergonomic way to check code with all features

[ghost]

Before #1331 make check was equivalent to cargo check --all --all-features --all-targets.

However, after #1331 the feature pairs leveldb-plain/leveldb-cmake and rdkafka-plain/rdkafka-cmake became mutually exclusive. These pairs of mutually exclusive features needed to ensure that all dependencies for leveldb and rdkafka are correctly written to Cargo.lock, so that Vector can be built with --freeze build flag. Cargo doesn't support defining mutually exclusive features yet (see rust-lang/cargo#2980), so the command in make check was changed to cargo check --all --all-targets.

It means that docker feature is not checked anymore when make check is called, although it is still compiled in CI as part of test-stable.

One approach is to change check-code target in the Makefile to something like

@cargo check --all  --all-targets
@cargo check --all  --features=nightly --all-targets
@cargo check --all  --features=docker --all-targets

However, this approach doesn't look like very elegant and there might be a better solution. I'd like to hear @LucioFranco's thoughts about this.

[LucioFranco]

So a couple of things, I am curious if there is a solution that doesn't use mutually exclusive feature flags. This in of it self breaks kinda how cargo handles feature flags as you can tell from the issue you linked. For me it's a bit important to not use make as I am using rust-analyzer which then uses cargo watch thus I would like to make sure we keep a workflow that is workable through cargo.

In the end, if the only feature flag that I need to add beyond default is docker, I think it is fine. But I'm not a big fan of having a huge array of feature flags and combinations which can lead us to missing things sometimes.

[ghost]

I was thinking about this, it could be fixed by adding support for building new versions of LevelDB in leveldb-sys create on GNU/Linux and macOS without cmake, but using only cc crate.

It would allow us to keep features for leveldb crate simple, just leveldb and leveldb,leveldb/cmake_build, so that two types of the builds would be not mutually exclusive.

[LucioFranco]

Seems like a good idea.

[jszwedko]

Closing this since it hasn't seemed to be an issue.