dev-dependencies.crate features leaked into dependencies.crate features

[lipanski]

I have a crate (let's call it greet) with a feature hello that is not enabled by default. I want to use this feature in my other crate (let's call it bug), but only when running tests. According to the cargo documentation this should be possible by using dev-dependencies.

However, I've noticed that features I enable in the dev-dependencies.greet block are also used when building my binary (e.g. cargo run or cargo build).

I'm using Rust 1.6.0 (but this was also happening in 1.5.0).

---

The greet crate:

# Cargo.toml

[package]
name = "greet"
version = "0.1.0"

[features]
default = []
hello = []

# src/lib.rs

#[cfg(feature = "hello")]
pub fn greeting() -> &'static str {
    "hello"
}

#[cfg(not(feature = "hello"))]
pub fn greeting() -> &'static str {
    "undefined"
}

The bug crate, using this previous crate greet:

# Cargo.toml

[package]
name = "bug"
version = "0.1.0"

[dependencies.greet]
path = "../greet"
features = []

[dev-dependencies.greet]
path = "../greet"
features = ["hello"]

# src/main.rs

extern crate greet;

fn main() {
    assert_eq!("undefined", greet::greeting());
}

#[cfg(test)]
mod tests {
    extern crate greet;

    #[test]
    fn assert_greeting() {
        assert_eq!("hello", greet::greeting());
    }
}

The assert on cargo test passes, the one on cargo run fails - even though I'm not enabling the hello feature in my dependencies.greet block.

I'd expect both assertions to pass.

[lipanski]

not sure if I should rather report it to cargo?!

indeed, it seems to be a duplicate of rust-lang/cargo#1796

so I guess we can close this one.