Refactor CI jobs to allow for more concurrency. (#505)

* Refactor CI jobs to allow for more concurrency.

* Switch all macOS runners to `macos-14`.

* Limit doc jobs to only Ubuntu.

.github/workflows/ci.yml

@@ -23,6 +23,14 @@ env:
 #
 # Using cargo-hack also allows us to more easily test the feature matrix of our packages.
 # We use --each-feature & --optional-deps which will run a separate check for every feature.
+#
+# We use macos-14 explictly instead of macos-latest because:
+#   * macos-latest currently points to macos-12
+#   * macos-14 provides us with the GPU support we want for testing
+#   * macos-14 comes with the M1 CPU which compiles our code much faster than the older runners
+# This explicit dependency can be switched back to macos-latest once it points to macos-14,
+# which is expected to happen sometime in Q2 FY24 (April – June 2024).
+# https://github.blog/changelog/2024-01-30-github-actions-macos-14-sonoma-is-now-available/
 
 name: CI
 
@@ -31,9 +39,9 @@ on:
   merge_group:
 
 jobs:
-  rustfmt:
-    runs-on: ubuntu-latest
+  fmt:
     name: cargo fmt
+    runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
 
@@ -54,11 +62,71 @@ jobs:
       - name: check copyright headers
         run: bash .github/copyright.sh
 
+  clippy-stable:
+    name: cargo clippy
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [windows-latest, macos-14, ubuntu-latest]
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: restore cache
+        uses: Swatinem/rust-cache@v2
+
+      - name: install stable toolchain
+        uses: dtolnay/rust-toolchain@master
+        with:
+          toolchain: ${{ env.RUST_STABLE_VER }}
+          components: clippy
+
+      - name: install cargo-hack
+        uses: taiki-e/install-action@v2
+        with:
+          tool: cargo-hack
+
+      - name: install native dependencies
+        if: matrix.os == 'ubuntu-latest'
+        run: sudo apt-get update; sudo apt-get install --no-install-recommends libasound2-dev libudev-dev
+
+      - name: cargo clippy
+        run: cargo hack clippy --workspace --each-feature --optional-deps -- -D warnings
+
+      - name: cargo clippy (auxiliary)
+        run: cargo hack clippy --workspace --each-feature --optional-deps --tests --benches --examples -- -D warnings
+
+  clippy-stable-wasm:
+    name: cargo clippy (wasm32)
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: restore cache
+        uses: Swatinem/rust-cache@v2
+
+      - name: install stable toolchain
+        uses: dtolnay/rust-toolchain@master
+        with:
+          toolchain: ${{ env.RUST_STABLE_VER }}
+          targets: wasm32-unknown-unknown
+          components: clippy
+
+      - name: install cargo-hack
+        uses: taiki-e/install-action@v2
+        with:
+          tool: cargo-hack
+
+      - name: cargo clippy
+        run: cargo hack clippy --workspace --target wasm32-unknown-unknown --each-feature --optional-deps -- -D warnings
+
+      - name: cargo clippy (auxiliary)
+        run: cargo hack clippy --workspace --target wasm32-unknown-unknown --each-feature --optional-deps --tests --benches --examples -- -D warnings
+
   test-stable:
+    name: cargo test
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        # We use macos-14 as that is an arm runner. These have the virtgpu support we need
         os: [windows-latest, macos-14, ubuntu-latest]
         include:
           - os: ubuntu-latest
@@ -69,7 +137,6 @@ jobs:
             # TODO: The windows runners theoretically have CPU fallback for GPUs, but
             # this failed in initial testing
             gpu: 'no'
-    name: cargo clippy + test
     steps:
       - uses: actions/checkout@v4
 
@@ -82,11 +149,6 @@ jobs:
           toolchain: ${{ env.RUST_STABLE_VER }}
           components: clippy
 
-      - name: install cargo-hack
-        uses: taiki-e/install-action@v2
-        with:
-          tool: cargo-hack
-
       - name: install native dependencies
         if: matrix.os == 'ubuntu-latest'
         run: sudo apt-get update; sudo apt-get install --no-install-recommends libasound2-dev libudev-dev
@@ -101,20 +163,14 @@ jobs:
           sudo apt-get update
           sudo apt install -y xvfb libegl1-mesa libgl1-mesa-dri libxcb-xfixes0-dev mesa-vulkan-drivers
 
-      - name: cargo clippy
-        run: cargo hack clippy --workspace --each-feature --optional-deps -- -D warnings
-
-      - name: cargo clippy (auxiliary)
-        run: cargo hack clippy --workspace --each-feature --optional-deps --tests --benches --examples -- -D warnings
-
       - name: cargo test
         run: cargo test --workspace --all-features
         env:
           VELLO_CI_GPU_SUPPORT: ${{ matrix.gpu }}
 
-  clippy-stable-wasm:
+  test-stable-wasm:
+    name: cargo test (wasm32)
     runs-on: ubuntu-latest
-    name: cargo clippy + test (wasm32)
     steps:
       - uses: actions/checkout@v4
 
@@ -128,24 +184,13 @@ jobs:
           targets: wasm32-unknown-unknown
           components: clippy
 
-      - name: install cargo-hack
-        uses: taiki-e/install-action@v2
-        with:
-          tool: cargo-hack
-
-      - name: cargo clippy
-        run: cargo hack clippy --workspace --target wasm32-unknown-unknown --each-feature --optional-deps -- -D warnings
-
-      - name: cargo clippy (auxiliary)
-        run: cargo hack clippy --workspace --target wasm32-unknown-unknown --each-feature --optional-deps --tests --benches --examples -- -D warnings
-
       # TODO: Find a way to make tests work. Until then the tests are merely compiled.
       - name: cargo test compile
         run: cargo test --workspace --target wasm32-unknown-unknown --all-features --no-run
 
-  android-stable-check:
-    runs-on: ubuntu-latest
+  check-stable-android:
     name: cargo check (aarch64-android)
+    runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
 
@@ -167,12 +212,11 @@ jobs:
           # This is a bit of a hack, but cargo apk doesn't seem to allow customising this
           RUSTFLAGS: '-D warnings'
 
-  docs:
+  doc:
     name: cargo doc
-    runs-on: ${{ matrix.os }}
-    strategy:
-      matrix:
-        os: [windows-latest, macos-latest, ubuntu-latest]
+    # NOTE: We don't have any platform specific docs in this workspace, so we only run on Ubuntu.
+    #       If we get per-platform docs (win/macos/linux/wasm32/..) then doc jobs should match that.
+    runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4