Use official cfg(docsrs) for doc_cfg

This reverts bf150aa.

.github/workflows/ci.yml

@@ -52,8 +52,6 @@ jobs:
       all-features: false
   tidy:
     uses: taiki-e/github-actions/.github/workflows/tidy.yml@main
-    with:
-      known-cfgs: assert_unmoved_doc_cfg
 
   test:
     strategy:

Cargo.toml

@@ -15,7 +15,6 @@ and mutably accessed.
 
 [package.metadata.docs.rs]
 all-features = true
-rustdoc-args = ["--cfg", "assert_unmoved_doc_cfg"]
 targets = ["x86_64-unknown-linux-gnu"]
 
 [package.metadata.cargo_check_external_types]

src/assert_unmoved.rs

@@ -181,7 +181,7 @@ impl<F: Future> Future for AssertUnmoved<F> {
 }
 
 #[cfg(feature = "futures03")]
-#[cfg_attr(assert_unmoved_doc_cfg, doc(cfg(feature = "futures03")))]
+#[cfg_attr(docsrs, doc(cfg(feature = "futures03")))]
 mod futures03 {
     use core::{
         pin::Pin,
@@ -321,7 +321,7 @@ mod futures03 {
 }
 
 #[cfg(feature = "tokio1")]
-#[cfg_attr(assert_unmoved_doc_cfg, doc(cfg(feature = "tokio1")))]
+#[cfg_attr(docsrs, doc(cfg(feature = "tokio1")))]
 mod tokio1 {
     use core::{
         pin::Pin,

src/lib.rs

@@ -130,8 +130,8 @@ Note: The MSRV when these features are enabled depends on the MSRV of these crat
     // clippy::std_instead_of_alloc,
     clippy::std_instead_of_core,
 )]
-// docs.rs only (cfg is enabled via [package.metadata.docs.rs] in Cargo.toml, not build script)
-#![cfg_attr(assert_unmoved_doc_cfg, feature(doc_cfg))]
+// docs.rs only (cfg is enabled by docs.rs, not build script)
+#![cfg_attr(docsrs, feature(doc_cfg))]
 
 #[cfg(test)]
 #[path = "gen/assert_impl.rs"]