Official configuration file describing build configurations

Hi all,

I remember having seen something similar (listing different ways to build a crate) but I don't remember where and if it was "official" (or at least largely adopted by the community).

Essentially I'm looking for something where I can describe the different ways a crate could be used. I would use this from my CI to test all those configurations. I would also use it to generate the initializationOptions of rust-analyzer. It could look something like this (hypothetical TOML file):

# Use default features and host target.

default-features = false

default-features = false
features = ["alloc"]

features = ["log"]

target = "riscv32imc-unknown-none-elf"
default-features = false
features = ["defmt"]

# Use default features.

From this, my CI could run something like this:

cargo check
cargo check --no-default-features
cargo check --no-default-features --features=alloc
cargo check --features=log
cargo check --target=riscv32imc-unknown-none-elf --no-default-features --features=defmt
cargo test
cargo fmt -- --check
cargo clippy -- --deny=warnings
cargo clippy --no-default-features -- --deny=warnings
cargo clippy --no-default-features --features=alloc -- --deny=warnings
cargo clippy --features=log -- --deny=warnings
cargo clippy --target=riscv32imc-unknown-none-elf --no-default-features --features=defmt -- --deny=warnings

Notice how cargo fmt -- --check is always added and cargo clippy is always matching the cargo check.

Could it have been one of the various tasks runner / make replacements out there? Like GitHub - sagiegurari/cargo-make: Rust task runner and build tool.?

It might have been something like that yes, but not that one. That one provides too much flexibility, and is a tool. I'm more looking into just a shared representation for different tools. It should really just be a list of "environments" (i.e. set of cargo and rustc flags).