Enable configuration-gated admonitions on feature-gated APIs in nightly

.github/workflows/publish-docs.yml

@@ -18,7 +18,7 @@ jobs:
           toolchain: "nightly"
           default: true
 
-      - run: cargo doc --no-deps --features cookies,json
+      - run: cargo doc --no-deps --features cookies,json,nightly
 
       - uses: JamesIves/github-pages-deploy-action@releases/v3
         with:

Cargo.toml

@@ -13,7 +13,7 @@ edition = "2018"
 exclude = [".*", "benchmarks", "media", "src/cookies/psl/list/*/"]
 
 [package.metadata.docs.rs]
-features = ["cookies", "json"]
+features = ["cookies", "json", "nightly"]
 
 [badges.maintenance]
 status = "actively-developed"
@@ -23,6 +23,7 @@ default = ["http2", "static-curl", "text-decoding"]
 cookies = ["httpdate"]
 http2 = ["curl/http2"]
 json = ["serde", "serde_json"]
+nightly = []
 psl = ["httpdate", "parking_lot", "publicsuffix"]
 spnego = ["curl-sys/spnego"]
 static-curl = ["curl/static-curl"]

src/lib.rs

@@ -220,6 +220,8 @@
     html_favicon_url = "https://raw.githubusercontent.com/sagebind/isahc/master/media/icon.png"
 )]
 #![deny(unsafe_code)]
+#![cfg_attr(feature = "nightly", feature(doc_cfg))]
+#![cfg_attr(feature = "nightly", feature(doc_auto_cfg))]
 #![warn(
     future_incompatible,
     missing_debug_implementations,