CI: Run tests on aarch64-apple-darwin and aarch64-apple-ios-sim.

.github/workflows/tests.yml

@@ -38,7 +38,6 @@ jobs:
           cargo generate-lockfile -Z minimal-versions
           cargo test --features=custom,std
 
-  # TODO: add aarch64-based macOS runner when it's supported by Github Actions
   main-tests:
     name: Tier 1 Test
     runs-on: ${{ matrix.os }}
@@ -48,8 +47,12 @@ jobs:
         toolchain: [nightly, beta, stable, 1.36]
         # Only Test macOS on stable to reduce macOS CI jobs
         include:
+          # x86_64-apple-darwin.
           - os: macos-12
             toolchain: stable
+          # aarch64-apple-darwin.
+          - os: macos-14
+            toolchain: stable
     steps:
       - uses: actions/checkout@v3
       - uses: dtolnay/rust-toolchain@master
@@ -84,18 +87,43 @@ jobs:
 
   ios-tests:
     name: iOS Simulator Test
-    runs-on: macos-12
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [macos-12, macos-14]
+        # Only test on stable to reduce macOS CI jobs
+        toolchain: [stable]
+        include:
+          # The Aarch64 device simulator doesn't seem to work on an x86-64 host
+          # and the x86_64 device simulator doesn't seem to work on an Aarch64
+          # host, at least within GitHub Actions.
+          - os: macos-12
+            target: x86_64-apple-ios
+            ios_platform: auto-ios-x86_64
+          - os: macos-14
+            target: aarch64-apple-ios-sim
+            ios_platform: auto-ios-aarch64-sim
     steps:
       - uses: actions/checkout@v3
       - uses: dtolnay/rust-toolchain@stable
         with:
-          targets: x86_64-apple-ios
+          targets: ${{ matrix.target }}
+      # There is no precompiled cargo-dinghy for Aarch64. The precompiled
+      # x86_64 binary runs on ARM64 macOS via Rosetta 2, but it fails to
+      # correctly interface with macOS toolchain.
       - name: Install precompiled cargo-dinghy
+        if: ${{ matrix.target == 'x86_64-apple-ios' }}
         run: |
           VERSION=0.6.2
           URL="https://github.com/sonos/dinghy/releases/download/${VERSION}/cargo-dinghy-macos-${VERSION}.tgz"
           wget -O - $URL | tar -xz --strip-components=1 -C ~/.cargo/bin
-          cargo dinghy --version
+      - name: cargo install cargo-dinghy
+        if: ${{ matrix.target == 'aarch64-apple-ios-sim' }}
+        run: |
+          VERSION=0.6.2
+          cargo install cargo-dinghy --version ${VERSION}
+      - name: Check cargo-dinghy version.
+        run: cargo dinghy --version
       - name: Setup Simulator
         # Use the first installed iOS runtime and the first (i.e. oldest) supported iPhone device.
         run: |
@@ -110,7 +138,7 @@ jobs:
           echo "device=$SIM_ID" >> $GITHUB_ENV
       - uses: Swatinem/rust-cache@v2
       - name: Run tests
-        run: cargo dinghy -d ${{ env.device }} test
+        run: cargo dinghy -p ${{ matrix.ios_platform }} -d ${{ env.device }} test
 
   windows-tests:
     name: Windows Test

src/error_impls.rs

@@ -1,7 +1,6 @@
 extern crate std;
 
 use crate::Error;
-use core::convert::From;
 use std::io;
 
 impl From<Error> for io::Error {