Build documentation on CI

.github/workflows/ci.yml

@@ -7,7 +7,7 @@ on:
 name: Continuous integration
 
 jobs:
-  ci:
+  tests:
     name: Rust project
     runs-on: ubuntu-latest
     strategy:
@@ -47,3 +47,22 @@ jobs:
         with:
           command: clippy
           args: --all-features --all-targets -- -D warnings
+
+  docs:
+    name: Documentation build
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v2
+
+      - uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: nightly
+          override: true
+
+      - name: Build documentation
+        env:
+          # Build the docs like docs.rs builds it
+          RUSTDOCFLAGS: --cfg docsrs
+        run: cargo doc --all-features