Prefix assertion command with user specified command

[azriel91]

Hiya! I'm wondering if it's a good idea to allow users to prefix an assertion command with their own command. The use case is being able to run a cargo binary / example under kcov or some other wrapper tool.

What it could look like:

#[test]
fn menu_example() {
    let kcov_command = &[
        "kcov",
        &format!("--include-pattern={}/src", env!("CARGO_MANIFEST_DIR")),
        &format!("{}/coverage", env!("CARGO_TARGET_DIR"))
    ];

    assert_cli::Assert::example("01_menu")
        .with_prefix(kcov_command)
        .stdin("exit\n")
        .unwrap();
}

[azriel91]

Hm, I just realized, it's meant to run something like:

kcov --include-pattern=/path/to/workspace/crate/src \
     /path/to/workspace/target/coverage \
     /path/to/workspace/target/debug/examples/01_menu

but instead it would run

kcov --include-pattern=/path/to/workspace/crate/src \
     /path/to/workspace/target/coverage \
     cargo run --example 01_menu

which wouldn't have line coverage tracked by kcov, since cargo is an intermediate binary.

ah well it was a nice thought; I'll have to live with sprinkling // kcov-ignores and // covered by integration test everywhere then

[azriel91]

See assert-rs/assert_cmd#9 where this may be addressed.