Cargo build with multi features

[u2]

ENV:

➜  cita-crypto git:(cache_ci_target) ✗ cargo --version                          
cargo 0.24.0-nightly (5bb478a51 2017-11-29)

➜  cita-crypto git:(cache_ci_target) ✗ rustc --version
rustc 1.24.0-nightly (8503b3ff8 2017-12-04)

It only works like cargo build --features 'sm2 sm3hash kafka',
but if I removed the quotes,

cargo build --features secp256k1 sha3hash
error: Invalid arguments.

Usage:
    cargo build [options]

But both work for cargo test

➜  cita-crypto git:(cache_ci_target) ✗ cargo test --no-run --features "secp256k1 sha3hash"
    Finished dev [unoptimized + debuginfo] target(s) in 0.0 secs
➜  cita-crypto git:(cache_ci_target) ✗ cargo test --no-run --features secp256k1 sha3hash  
    Finished dev [unoptimized + debuginfo] target(s) in 0.0 secs

so, why it's different? Is it a bug?

[alexcrichton]

Thanks for the report! This has to do with CLI parsing and shells and whatnot. When you use quotes it's passed as a single CLI argument which is then interpreted as the value for the --features flag. When you don't use quotes it's passed as two separate arguments, one which is interpreted as the value of the --features flag and one which is a bare argument to Cargo.

cargo build takes no arguments (hence the "Invalid arguments") and carog test takes arguments which are forwarded to the test binaries (hence the valid run). cargo test --no-run --features secp256k1 sha3hash is not what you want though as it does not enable the sha3hash feature, it only enables the secp256k1 feature.

[u2]

Thank you

[fan-tom]

cargo test --no-run --features secp256k1 sha3hash is not what you want though as it does not enable the sha3hash feature, it only enables the secp256k1 feature.

Is it documented anywhere? A have spent about a hour figuring out why only the first feature is passed to rustc, using --verbose until I found this issue. cargo test --help says only that --features accepts space-separated list of features, not that it must be enclosed by quotes

[artmg]

try " " double quotes around multiple features in cargo commands

[rootkea]

cargo test --help says only that --features accepts space-separated list of features, not that it must be enclosed by quotes

Yes. From cargo build --help:

--features <FEATURES>...     Space or comma separated list of features to activate

It doesn't say anything about that Space or comma separated list be enclosed by quotes.