log runtime of arbitrary scope

This crate is part of the gitui project and can be used to annotate arbitrary scopes to trace their execution times via log:

in your crate:

[dependencies]
scopetime = "0.1"

in your code:

fn foo(){
    scope_time!("foo");

    // ... do something u wanna measure
}

the resulting log looks something like this:

19:45:00 [TRACE] (7) scopetime: [scopetime/src/lib.rs:34] scopetime: 2 ms [my_crate::foo] @my_crate/src/bar.rs:5