This changes the test setup to use our own client rather than using
reqwest directly. Allows us to add several quality of life features like
always unwrapping results.
This improves compiles further when using lots of nested routes. Such as
the example posted
[here](https://github.com/tokio-rs/axum/issues/200#issuecomment-902541073).
It seems rustc is really slow at checking bounds on these kinds of
intermediate builder methods. Should probably file an issue about that.
This way there is now only one way to create a router:
```rust
use axum::{Router, handler::get};
let app = Router::new()
.route("/foo", get(handler))
.route("/foo", get(handler));
```
`nest` was changed in the same way:
```rust
use axum::Router;
let app = Router::new().nest("/foo", service);
```
Previously, on `main`, this wouldn't compile:
```rust
let app = route("/", get(handler))
.layer(
ServiceBuilder::new()
.timeout(Duration::from_secs(10))
.into_inner(),
)
.handle_error(...)
.route(...); // <-- doesn't work
```
That is because `handle_error` would be
`axum::service::ServiceExt::handle_error` which returns `HandleError<_,
_, _, HandleErrorFromService>` which does _not_ implement `RoutingDsl`.
So you couldn't call `route`. This was caused by
https://github.com/tokio-rs/axum/pull/120.
Basically `handle_error` when called on a `RoutingDsl`, the resulting
service should also implement `RoutingDsl`, but if called on another
random service it should _not_ implement `RoutingDsl`.
I don't think thats possible by having `handle_error` on `ServiceExt`
which is implemented for any service, since all axum routers are also
services by design.
This resolves the issue by removing `ServiceExt` and moving its methods
to `RoutingDsl`. Then we have more tight control over what has a
`handle_error` method.
`service::OnMethod` now also has a `handle_error` so you can still
handle errors from random services, by doing
`service::any(svc).handle_error(...)`.
David Pedersen