ci: Improve the tests workflow

- Move to ubuntu-latest, for better performance.
- Use NDK and SDK preinstalled on the runner image.
- Cache AVD snapshot.

.github/workflows/tests.yml

@@ -2,7 +2,7 @@ name: tests
 on: [push, pull_request]
 jobs:
   tests:
-    runs-on: macos-12
+    runs-on: ubuntu-latest
     strategy:
       matrix:
         api: [26, 27, 28, 29, 30, 31]
@@ -15,42 +15,35 @@ jobs:
     env:
       ANDROID_EMULATOR_WAIT_TIME_BEFORE_KILL: 200 # Default is 20
     steps:
-      # can update to a newer version through https://developer.android.com/studio#downloads
-      - run: curl https://dl.google.com/android/repository/commandlinetools-mac-8512546_latest.zip -o /tmp/sdk.zip
-      - run: unzip -d /tmp/sdk /tmp/sdk.zip
-      - run: mkdir -p ~/Library/Android/Sdk/tools
-      - run: cp -r /tmp/sdk/cmdline-tools/* ~/Library/Android/Sdk/tools
-
-      - run: "echo y | ~/Library/Android/Sdk/tools/bin/sdkmanager tools --sdk_root=~/Library/Android/Sdk"
-      - run: "~/Library/Android/Sdk/tools/bin/sdkmanager platform-tools --sdk_root=~/Library/Android/Sdk"
-      - run: "~/Library/Android/Sdk/tools/bin/sdkmanager 'ndk;25.1.8937393' --sdk_root=~/Library/Android/Sdk"
-      - run: "~/Library/Android/Sdk/tools/bin/sdkmanager 'build-tools;33.0.0' --sdk_root=~/Library/Android/Sdk"
-
-      - uses: actions/checkout@v3
-      - run: |
-          echo "#!/bin/sh" >> /tmp/android_env
-          echo "export PATH=$PATH:/Users/runner/Library/Android/Sdk/build-tools/33.0.0" >> /tmp/android_env
-          echo "export ANDROID_SDK_ROOT=/Users/runner/Library/Android/Sdk" >> /tmp/android_env
-          echo "export ANDROID_API_LEVEL=${{ matrix.api }}" >> /tmp/android_env
-          case ${{ matrix.arch }} in
-            arm64-v8a)
-              echo "export ANDROID_ARCH=arm64" >> /tmp/android_env
-              echo "export ANDROID_ABI=arm64-v8a" >> /tmp/android_env
-              ;;
-            x86)
-              echo "export ANDROID_ARCH=${{ matrix.arch }}" >> /tmp/android_env
-              echo "export ANDROID_ABI=${{ matrix.arch }}" >> /tmp/android_env
-              echo "export ANDROID_LIBDIR=/system/lib" >> /tmp/android_env
-              ;;
-            *)
-              echo "export ANDROID_ARCH=${{ matrix.arch }}" >> /tmp/android_env
-              echo "export ANDROID_ABI=${{ matrix.arch }}" >> /tmp/android_env
-              ;;
-          esac
-          chmod +x /tmp/android_env
+      - name: Enable KVM
+        run: |
+          echo 'KERNEL=="kvm", GROUP="kvm", MODE="0666", OPTIONS+="static_node=kvm"' | sudo tee /etc/udev/rules.d/99-kvm4all.rules
+          sudo udevadm control --reload-rules
+          sudo udevadm trigger --name-match=kvm
+      - name: AVD cache
+        uses: actions/cache@v4
+        id: avd-cache
+        with:
+          path: |
+            ~/.android/avd/*
+            ~/.android/adb*
+          key: avd-${{ matrix.api }}
+      - name: Create AVD and generate snapshot for caching
+        if: steps.avd-cache.outputs.cache-hit != 'true'
+        uses: reactivecircus/android-emulator-runner@v2
+        with:
+          api-level: ${{ matrix.api }}
+          arch: ${{ matrix.arch }}
+          force-avd-creation: false
+          emulator-options: -no-window -gpu swiftshader_indirect -noaudio -no-boot-anim -camera-back none
+          disable-animations: false
+          script: echo "Generated AVD snapshot for caching."
       - name: Run tests in emulator
         uses: reactivecircus/android-emulator-runner@v2
         with:
           api-level: ${{ matrix.api }}
           arch: ${{ matrix.arch }}
-          script: source /tmp/android_env && make check
+          force-avd-creation: false
+          emulator-options: -no-snapshot-save -no-window -gpu swiftshader_indirect -noaudio -no-boot-anim -camera-back none
+          disable-animations: true
+          script: make check