Test docs.rs documentation build in CI

Author: dtolnay

.github/workflows/ci.yml

@@ -51,6 +51,20 @@ jobs:
       - run: cargo generate-lockfile -Z minimal-versions
       - run: cargo check --locked
 
+  doc:
+    name: Documentation
+    needs: pre_ci
+    if: needs.pre_ci.outputs.continue
+    runs-on: ubuntu-latest
+    timeout-minutes: 45
+    env:
+      RUSTDOCFLAGS: -Dwarnings
+    steps:
+      - uses: actions/checkout@v4
+      - uses: dtolnay/rust-toolchain@nightly
+      - uses: dtolnay/install@cargo-docs-rs
+      - run: cargo docs-rs
+
   clippy:
     name: Clippy
     runs-on: ubuntu-latest