RUST-408 Generate API documentation for the sync API on docs.rs (#173)

Author: saghm

Cargo.toml

@@ -82,3 +82,6 @@ function_name = "0.2.0"
 pretty_assertions = "0.6.1"
 serde_json = "1.0.40"
 semver = "0.9.0"
+
+[package.metadata.docs.rs]
+rustdoc-args = ["--cfg", "docsrs"]

src/lib.rs

@@ -77,6 +77,7 @@
         clippy::float_cmp
     )
 )]
+#![cfg_attr(docsrs, feature(doc_cfg))]
 
 macro_rules! define_if_single_runtime_enabled {
     ( $( $def:item )+ ) => {
@@ -113,7 +114,8 @@ define_if_single_runtime_enabled! {
     mod sdam;
     mod selection_criteria;
     mod srv;
-    #[cfg(feature = "sync")]
+    #[cfg(any(feature = "sync", docsrs))]
+    #[cfg_attr(docsrs, doc(cfg(feature = "sync")))]
     pub mod sync;
     #[cfg(test)]
     mod test;

src/sync/mod.rs

@@ -1,3 +1,5 @@
+//! Contains the sync API. This is only available when the `sync` feature is enabled.
+
 mod client;
 mod coll;
 mod cursor;