docs: document features

closes #3

Cargo.toml

@@ -56,6 +56,8 @@ plotters = { version = "^0.3.5", default-features = false, features = [
 codspeed = { version = "2.4.1", optional = true }
 colored = { version = "2.1.0", optional = true }
 
+document-features = { version = "0.2", optional = true }
+
 [dev-dependencies]
 tempfile = "3.10.1"
 approx = "0.5.1"
@@ -75,16 +77,20 @@ stable = [
   "async_std",
 ]
 default = ["rayon", "plotters", "cargo_bench_support"]
+
+## Enables [codspeed](https://codspeed.io)
 codspeed = ["dep:codspeed", "dep:colored"]
 
-# Enable async/await support
+## Enables async/await support
 async = []
 
-# These features enable built-in support for running async benchmarks on each different async
-# runtime.
+## Enables built-in support for running async benchmarks on futures.
 async_futures = ["futures/executor", "async"]
+## Enables built-in support for running async benchmarks on smol.
 async_smol = ["smol", "async"]
+## Enables built-in support for running async benchmarks on tokio.
 async_tokio = ["tokio", "async"]
+## Enables built-in support for running async benchmarks on async-std.
 async_std = ["async-std", "async"]
 
 # This feature _currently_ does nothing except disable a warning message, but in 0.4.0 it will be

src/lib.rs

@@ -14,6 +14,11 @@
 //!   to performance are real, not measurement noise.
 //! * Produces detailed charts, providing thorough understanding of your code's
 //!   performance behavior.
+//!
+//! ## Feature flags
+#![cfg_attr(feature = "document-features", doc = document_features::document_features!())]
+#![cfg_attr(docsrs, feature(doc_auto_cfg))]
+//!
 
 #![allow(clippy::style, clippy::complexity)]
 #![warn(bare_trait_objects)]