e1e3431bc4
This backports PR #1233 to v0.1.x. This isn't *just* a simple cherry-pick because the new tests in that branch use the v0.2.x module names, so that had to be fixed. Otherwise, though, it's the same change, and I'll go ahead and merge it when CI passes, since it was approved on `master`. ## Motivation Currently, using `#[instrument(err)]` on a function returning a `Result` with an `impl Trait` in it results in a compiler error. This is because we generate a type annotation on the closure in the function body that contains the user function's actual body, and `impl Trait` isn't allowed on types in local bindings, only on function parameters and return types. ## Solution This branch fixes the issue by simply removing the return type annotation from the closure. I've also added tests that break on master for functions returning `impl Trait`, both with and without the `err` argument. Fixes #1227 Signed-off-by: Eliza Weisman <eliza@buoyant.io>
tracing-attributes
Macro attributes for application-level tracing.
Overview
tracing is a framework for instrumenting Rust programs to collect
structured, event-based diagnostic information. This crate provides the
#[instrument] attribute for automatically instrumenting functions using
tracing.
Note that this macro is also re-exported by the main tracing crate.
Compiler support: requires rustc 1.42+
Usage
First, add this to your Cargo.toml:
[dependencies]
tracing-attributes = "0.1.12"
This crate provides the #[instrument] attribute for instrumenting a function
with a tracing span. For example:
use tracing_attributes::instrument;
#[instrument]
pub fn my_function(my_arg: usize) {
// ...
}
Supported Rust Versions
Tracing is built against the latest stable release. The minimum supported version is 1.42. The current Tracing version is not guaranteed to build on Rust versions earlier than the minimum supported version.
Tracing follows the same compiler support policies as the rest of the Tokio project. The current stable Rust compiler and the three most recent minor versions before it will always be supported. For example, if the current stable compiler version is 1.45, the minimum supported version will not be increased past 1.42, three minor versions prior. Increasing the minimum supported compiler version is not considered a semver breaking change as long as doing so complies with this policy.
License
This project is licensed under the MIT license.
Contribution
Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in Tokio by you, shall be licensed as MIT, without any additional terms or conditions.