Match CI doc testing with docs.rs. (#734)

* Remove `-Zunstable-options -Zrustdoc-scrape-examples` from CI. It
wasn't even enabled for docs.rs and we don't have any examples by
Cargo's definition, so not worth enabling scraping at this point.
* Treat doc warnings as errors. Historically we've not done so due to
various `rustdoc` bugs giving false positives but I got it to pass
without failure right now, so perhaps better times have arrived.
* Pass `--all-features` at docs.rs to match our CI and reduce the
maintenance burden of manually syncing the features list.
* Target only `x86_64-unknown-linux-gnu` on docs.rs as we don't have any
platform specific docs.
* Enable the `doc_auto_cfg` feature for docs.rs which will show a little
tip next to feature gated functionality informing of the crate feature
flag.

.github/workflows/ci.yml

@@ -366,15 +366,17 @@ jobs:
         with:
           save-if: ${{ github.event_name != 'merge_group' }}
 
-      # We test documentation using nightly to match docs.rs. This prevents potential breakages
+      # We test documentation using nightly to match docs.rs.
       - name: cargo doc
-        run: cargo doc --workspace --locked --all-features --no-deps --document-private-items -Zunstable-options -Zrustdoc-scrape-examples
+        run: cargo doc --workspace --locked --all-features --no-deps --document-private-items
+        env:
+          RUSTDOCFLAGS: '--cfg docsrs -D warnings'
 
-  # If this fails, consider changing your text or adding something to .typos.toml
+  # If this fails, consider changing your text or adding something to .typos.toml.
   typos:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
 
       - name: check typos
-        uses: crate-ci/typos@v1.26.0
+        uses: crate-ci/typos@v1.27.0

examples/scenes/src/test_scenes.rs

@@ -82,7 +82,7 @@ export_scenes!(
 );
 
 /// Implementations for the test scenes.
-/// In a module because the exported [`ExampleScene`](crate::ExampleScene) creation functions use the same names.
+/// In a module because the exported [`ExampleScene`] creation functions use the same names.
 mod impls {
     use std::f64::consts::PI;
 

vello/Cargo.toml

@@ -9,6 +9,12 @@ rust-version.workspace = true
 license.workspace = true
 repository.workspace = true
 
+[package.metadata.docs.rs]
+all-features = true
+# There are no platform specific docs.
+default-target = "x86_64-unknown-linux-gnu"
+targets = []
+
 [features]
 default = ["wgpu"]
 # Enables GPU memory usage estimation. This performs additional computations

vello/src/lib.rs

@@ -81,6 +81,8 @@
 //!
 //! See the [`examples/`](https://github.com/linebender/vello/tree/main/examples) folder to see how that code integrates with frameworks like winit.
 
+#![cfg_attr(docsrs, feature(doc_auto_cfg))]
+
 mod debug;
 mod recording;
 mod render;

vello/src/wgpu_engine.rs

@@ -38,7 +38,7 @@ pub(crate) struct WgpuEngine {
     #[cfg(not(target_arch = "wasm32"))]
     shaders_to_initialise: Option<Vec<UninitialisedShader>>,
     pub(crate) use_cpu: bool,
-    /// Overrides from a specific `Image`'s [`id`](peniko::Image::id) to a wgpu `Texture`.
+    /// Overrides from a specific `Image::data`'s [`id`](peniko::Blob::id) to a wgpu `Texture`.
     ///
     /// The `Texture` should have the same size as the `Image`.
     pub(crate) image_overrides: HashMap<u64, wgpu::ImageCopyTextureBase<Arc<Texture>>>,

vello_encoding/Cargo.toml

@@ -7,6 +7,12 @@ rust-version.workspace = true
 license.workspace = true
 repository.workspace = true
 
+[package.metadata.docs.rs]
+all-features = true
+# There are no platform specific docs.
+default-target = "x86_64-unknown-linux-gnu"
+targets = []
+
 [features]
 default = ["full"]
 

vello_encoding/src/lib.rs

@@ -3,6 +3,8 @@
 
 //! Raw scene encoding.
 
+#![cfg_attr(docsrs, feature(doc_auto_cfg))]
+
 mod binning;
 mod clip;
 mod config;

vello_shaders/Cargo.toml

@@ -7,6 +7,12 @@ rust-version.workspace = true
 license.workspace = true
 repository.workspace = true
 
+[package.metadata.docs.rs]
+all-features = true
+# There are no platform specific docs.
+default-target = "x86_64-unknown-linux-gnu"
+targets = []
+
 [features]
 default = ["wgsl", "full", "cpu"]
 compile = ["dep:naga", "dep:thiserror"]

vello_shaders/src/lib.rs

@@ -17,6 +17,8 @@
 //!
 //! [Vello]: https://github.com/linebender/vello
 
+#![cfg_attr(docsrs, feature(doc_auto_cfg))]
+
 mod types;
 
 #[cfg(feature = "compile")]