Add tests for ext traits + rename traits

[mmastrac]

This adds tests for the ext traits. I've also renamed the traits to FutureTimerExt and StreamTimerExt because they were conflicting with the built-in futures FutureExt and StreamExt.

[yoshuawuyts]

because they were conflicting with the built-in futures FutureExt and StreamExt

If we're to follow the extension trait naming conventions defined in RFC0445 we should probably keep naming these traits FutureExt and StreamExt.

Also I just checked in the playground, and it doesn't seem like extension trait names conflict with each other. The following compiles without a problem:

mod foo {
    pub trait ResultExt {}
    impl<T,E> ResultExt for Result<T, E> {}
}

mod bar {
    pub trait ResultExt {}
    impl<T,E> ResultExt for Result<T, E> {}
}

use foo::*;
use bar::*;

fn main () -> Result<(), std::io::Error> {
    Ok(())
}

[mmastrac]

Interesting. I had some local conflicts, but I can try to poke around them a bit more and see if I can resolve it.

[mmastrac]

Ok, so it looks like Rust allows you to import the same type more than one time, but trying to use extension methods from both just doesn't work. I modified your test case to show this happening:

mod foo {
    pub trait ResultExt {
        fn a(&self);
    }
    impl<T,E> ResultExt for Result<T, E> {
        fn a(&self) {}
    }
}

mod bar {
    pub trait ResultExt {
        fn b(&self);
    }
    impl<T,E> ResultExt for Result<T, E> {
        fn b(&self) {}
    }
}

use foo::*;
use bar::*;

fn main () -> Result<(), std::io::Error> {
    let x = Ok(());
    x.a();
    x.b();
    x
}

[mmastrac]

Looks like tokio is taking the path of duplicating the names for extension traits: rust-lang/rust#54156

It might make sense to follow that path and see how rust core handles conflicts.

[yoshuawuyts]

💯