Add in-repo action integration tests

Bring the integration tests from the separate cache-apt-pkgs-action-ci
repo into this repo. Tests now use `uses: ./` to test the local checkout
directly, eliminating the need for cross-repo dispatch events.

Tests cover:
- Core workflow: install, restore, cache invalidation, package ordering
- Error handling: empty packages, missing packages, invalid version
- Regression tests: issues #36, #37, #72, #76, #79, #81, #84, #89, #98, #106
- Special cases: multi-arch cache keys, virtual packages

Changes from the external CI tests:
- Uses `uses: ./` instead of `uses: awalsh128/cache-apt-pkgs-action@master`
- Updated checkout to actions/checkout@v4
- Made version-list assertions resilient (grep for expected packages
  rather than exact string match, since dependency versions change
  with Ubuntu updates)
- Improved error-case verification (check outcome != failure rather
  than only running on failure)
- Triggers on push to master/dev/staging and on pull requests

Co-developed-by: Claude Code v2.1.58 (claude-opus-4-6)

.github/workflows/action-tests.yml

@@ -0,0 +1,475 @@
+name: Action Tests
+on:
+  workflow_dispatch:
+    inputs:
+      debug:
+        description: "Run in debug mode."
+        type: boolean
+        required: false
+        default: false
+  push:
+    branches: [master, dev, staging]
+  pull_request:
+    types: [opened, synchronize]
+
+env:
+  DEBUG: ${{ github.event.inputs.debug || false }}
+  # Test for overrides in built in shell options (regression issue 98).
+  SHELLOPTS: errexit:pipefail
+
+jobs:
+
+  # === Core Functionality ===
+
+  list_all_versions:
+    runs-on: ubuntu-latest
+    name: List all package versions (including deps).
+    steps:
+      - uses: actions/checkout@v4
+      - name: Execute
+        id: execute
+        uses: ./
+        with:
+          packages: xdot=1.3-1
+          version: ${{ github.run_id }}-${{ github.run_attempt }}-list_all_versions
+          debug: ${{ env.DEBUG }}
+      - name: Verify
+        run: |
+          echo "cache-hit = ${{ steps.execute.outputs.cache-hit }}"
+          echo "package-version-list = ${{ steps.execute.outputs.package-version-list }}"
+          echo "all-package-version-list = ${{ steps.execute.outputs.all-package-version-list }}"
+          # Verify cache miss on first run.
+          test "${{ steps.execute.outputs.cache-hit }}" = "false"
+          # Verify the main package is in the all-packages list.
+          echo "${{ steps.execute.outputs.all-package-version-list }}" | grep -q "xdot=1.3-1"
+        shell: bash
+
+  list_versions:
+    runs-on: ubuntu-latest
+    name: List package versions.
+    steps:
+      - uses: actions/checkout@v4
+      - name: Execute
+        id: execute
+        uses: ./
+        with:
+          packages: xdot rolldice
+          version: ${{ github.run_id }}-${{ github.run_attempt }}-list_versions
+          debug: ${{ env.DEBUG }}
+      - name: Verify
+        run: |
+          echo "cache-hit = ${{ steps.execute.outputs.cache-hit }}"
+          echo "package-version-list = ${{ steps.execute.outputs.package-version-list }}"
+          test "${{ steps.execute.outputs.cache-hit }}" = "false"
+          echo "${{ steps.execute.outputs.package-version-list }}" | grep -q "xdot="
+          echo "${{ steps.execute.outputs.package-version-list }}" | grep -q "rolldice="
+        shell: bash
+
+  standard_workflow_install:
+    runs-on: ubuntu-latest
+    name: Standard workflow install package and cache.
+    steps:
+      - uses: actions/checkout@v4
+      - name: Execute
+        id: execute
+        uses: ./
+        with:
+          packages: xdot rolldice
+          version: ${{ github.run_id }}-${{ github.run_attempt }}-standard_workflow
+          debug: ${{ env.DEBUG }}
+      - name: Verify
+        if: steps.execute.outputs.cache-hit != 'false'
+        run: |
+          echo "cache-hit = ${{ steps.execute.outputs.cache-hit }}"
+          exit 1
+        shell: bash
+
+  standard_workflow_install_with_new_version:
+    needs: standard_workflow_install
+    runs-on: ubuntu-latest
+    name: Standard workflow packages with new version.
+    steps:
+      - uses: actions/checkout@v4
+      - name: Execute
+        id: execute
+        uses: ./
+        with:
+          packages: xdot rolldice
+          version: ${{ github.run_id }}-${{ github.run_attempt }}-standard_workflow_install_with_new_version
+          debug: ${{ env.DEBUG }}
+      - name: Verify
+        if: steps.execute.outputs.cache-hit != 'false'
+        run: |
+          echo "cache-hit = ${{ steps.execute.outputs.cache-hit }}"
+          exit 1
+        shell: bash
+
+  standard_workflow_restore:
+    needs: standard_workflow_install
+    runs-on: ubuntu-latest
+    name: Standard workflow restore cached packages.
+    steps:
+      - uses: actions/checkout@v4
+      - name: Execute
+        id: execute
+        uses: ./
+        with:
+          packages: xdot rolldice
+          version: ${{ github.run_id }}-${{ github.run_attempt }}-standard_workflow
+          debug: ${{ env.DEBUG }}
+      - name: Verify
+        if: steps.execute.outputs.cache-hit != 'true'
+        run: |
+          echo "cache-hit = ${{ steps.execute.outputs.cache-hit }}"
+          exit 1
+        shell: bash
+
+  standard_workflow_restore_with_packages_out_of_order:
+    needs: standard_workflow_install
+    runs-on: ubuntu-latest
+    name: Standard workflow restore with packages out of order.
+    steps:
+      - uses: actions/checkout@v4
+      - name: Execute
+        id: execute
+        uses: ./
+        with:
+          packages: rolldice xdot
+          version: ${{ github.run_id }}-${{ github.run_attempt }}-standard_workflow
+          debug: ${{ env.DEBUG }}
+      - name: Verify
+        if: steps.execute.outputs.cache-hit != 'true'
+        run: |
+          echo "cache-hit = ${{ steps.execute.outputs.cache-hit }}"
+          exit 1
+        shell: bash
+
+  standard_workflow_add_package:
+    needs: standard_workflow_install
+    runs-on: ubuntu-latest
+    name: Standard workflow add another package.
+    steps:
+      - uses: actions/checkout@v4
+      - name: Execute
+        id: execute
+        uses: ./
+        with:
+          packages: xdot rolldice distro-info-data
+          version: ${{ github.run_id }}-${{ github.run_attempt }}-standard_workflow
+          debug: ${{ env.DEBUG }}
+      - name: Verify
+        if: steps.execute.outputs.cache-hit != 'false'
+        run: |
+          echo "cache-hit = ${{ steps.execute.outputs.cache-hit }}"
+          exit 1
+        shell: bash
+
+  standard_workflow_restore_add_package:
+    needs: standard_workflow_add_package
+    runs-on: ubuntu-latest
+    name: Standard workflow restore added package.
+    steps:
+      - uses: actions/checkout@v4
+      - name: Execute
+        id: execute
+        uses: ./
+        with:
+          packages: xdot rolldice distro-info-data
+          version: ${{ github.run_id }}-${{ github.run_attempt }}-standard_workflow
+          debug: ${{ env.DEBUG }}
+      - name: Verify
+        if: steps.execute.outputs.cache-hit != 'true'
+        run: |
+          echo "cache-hit = ${{ steps.execute.outputs.cache-hit }}"
+          exit 1
+        shell: bash
+
+  # === Error Handling ===
+
+  no_packages:
+    runs-on: ubuntu-latest
+    name: No packages passed.
+    steps:
+      - uses: actions/checkout@v4
+      - name: Execute
+        id: execute
+        uses: ./
+        with:
+          packages: ""
+        continue-on-error: true
+      - name: Verify
+        if: steps.execute.outcome != 'failure'
+        run: |
+          echo "Expected failure but got: ${{ steps.execute.outcome }}"
+          exit 1
+        shell: bash
+
+  package_not_found:
+    runs-on: ubuntu-latest
+    name: Package not found.
+    steps:
+      - uses: actions/checkout@v4
+      - name: Execute
+        id: execute
+        uses: ./
+        with:
+          packages: package_that_doesnt_exist
+        continue-on-error: true
+      - name: Verify
+        if: steps.execute.outcome != 'failure'
+        run: |
+          echo "Expected failure but got: ${{ steps.execute.outcome }}"
+          exit 1
+        shell: bash
+
+  version_contains_spaces:
+    runs-on: ubuntu-latest
+    name: Version contains spaces.
+    steps:
+      - uses: actions/checkout@v4
+      - name: Execute
+        id: execute
+        uses: ./
+        with:
+          packages: xdot
+          version: 123 abc
+          debug: ${{ env.DEBUG }}
+        continue-on-error: true
+      - name: Verify
+        if: steps.execute.outcome != 'failure'
+        run: |
+          echo "Expected failure but got: ${{ steps.execute.outcome }}"
+          exit 1
+        shell: bash
+
+  debug_disabled:
+    runs-on: ubuntu-latest
+    name: Debug disabled.
+    steps:
+      - uses: actions/checkout@v4
+      - uses: ./
+        with:
+          packages: xdot
+          version: ${{ github.run_id }}-${{ github.run_attempt }}-debug_disabled
+          debug: false
+
+  # === Regression Tests ===
+
+  regression_36:
+    runs-on: ubuntu-latest
+    name: "Reinstall existing package (regression issue #36)."
+    steps:
+      - uses: actions/checkout@v4
+      - uses: ./
+        with:
+          packages: libgtk-3-dev
+          version: ${{ github.run_id }}-${{ github.run_attempt }}-regression_36
+          debug: ${{ env.DEBUG }}
+
+  regression_37:
+    runs-on: ubuntu-latest
+    name: "Install with reported package deps not installed (regression issue #37)."
+    steps:
+      - uses: actions/checkout@v4
+      - uses: ./
+        with:
+          packages: libosmesa6-dev libgl1-mesa-dev python3-tk pandoc git-restore-mtime
+          version: ${{ github.run_id }}-${{ github.run_attempt }}-regression_37
+          debug: ${{ env.DEBUG }}
+
+  regression_72_1:
+    runs-on: ubuntu-latest
+    name: "Cache Java CA certs package v1 (regression issue #72)."
+    steps:
+      - uses: actions/checkout@v4
+      - uses: ./
+        with:
+          packages: openjdk-11-jre
+          version: ${{ github.run_id }}-${{ github.run_attempt }}-regression_72
+          debug: ${{ env.DEBUG }}
+
+  regression_72_2:
+    runs-on: ubuntu-latest
+    name: "Cache Java CA certs package v2 (regression issue #72)."
+    steps:
+      - uses: actions/checkout@v4
+      - uses: ./
+        with:
+          packages: default-jre
+          version: ${{ github.run_id }}-${{ github.run_attempt }}-regression_72
+          debug: ${{ env.DEBUG }}
+
+  regression_76:
+    runs-on: ubuntu-latest
+    name: "Cache empty archive (regression issue #76)."
+    steps:
+      - uses: actions/checkout@v4
+      - run: |
+          sudo wget -O- https://apt.repos.intel.com/intel-gpg-keys/GPG-PUB-KEY-INTEL-SW-PRODUCTS.PUB | gpg --dearmor | sudo tee /usr/share/keyrings/oneapi-archive-keyring.gpg > /dev/null;
+          echo "deb [signed-by=/usr/share/keyrings/oneapi-archive-keyring.gpg] https://apt.repos.intel.com/oneapi all main" | sudo tee /etc/apt/sources.list.d/oneAPI.list;
+          sudo apt-get -qq update;
+          sudo apt-get install -y intel-oneapi-runtime-libs intel-oneapi-runtime-opencl;
+          sudo apt-get install -y opencl-headers ocl-icd-opencl-dev;
+          sudo apt-get install -y libsundials-dev;
+      - uses: ./
+        with:
+          packages: intel-oneapi-runtime-libs
+          version: ${{ github.run_id }}-${{ github.run_attempt }}-regression_76
+          debug: ${{ env.DEBUG }}
+
+  regression_79:
+    runs-on: ubuntu-latest
+    name: "Tar error with libboost-dev (regression issue #79)."
+    steps:
+      - uses: actions/checkout@v4
+      - uses: ./
+        with:
+          packages: libboost-dev
+          version: ${{ github.run_id }}-${{ github.run_attempt }}-regression_79
+          debug: ${{ env.DEBUG }}
+
+  regression_81:
+    runs-on: ubuntu-latest
+    name: "Tar error with alsa-ucm-conf (regression issue #81)."
+    steps:
+      - uses: actions/checkout@v4
+      - uses: ./
+        with:
+          packages: libasound2 libatk-bridge2.0-0 libatk1.0-0 libatspi2.0-0 libcups2 libdrm2 libgbm1 libnspr4 libnss3 libxcomposite1 libxdamage1 libxfixes3 libxkbcommon0 libxrandr2
+          version: ${{ github.run_id }}-${{ github.run_attempt }}-regression_81
+          debug: ${{ env.DEBUG }}
+
+  regression_84_literal_block_install:
+    runs-on: ubuntu-latest
+    name: "Install multiline package listing - literal block (regression issue #84)."
+    steps:
+      - uses: actions/checkout@v4
+      - uses: ./
+        with:
+          packages: >
+            xdot
+            rolldice distro-info-data
+          version: ${{ github.run_id }}-${{ github.run_attempt }}-regression_84_literal_block
+          debug: ${{ env.DEBUG }}
+
+  regression_84_literal_block_restore:
+    needs: regression_84_literal_block_install
+    runs-on: ubuntu-latest
+    name: "Restore multiline package listing - literal block (regression issue #84)."
+    steps:
+      - uses: actions/checkout@v4
+      - name: Execute
+        id: execute
+        uses: ./
+        with:
+          packages: xdot rolldice distro-info-data
+          version: ${{ github.run_id }}-${{ github.run_attempt }}-regression_84_literal_block
+          debug: ${{ env.DEBUG }}
+      - name: Verify
+        if: steps.execute.outputs.cache-hit != 'true'
+        run: |
+          echo "cache-hit = ${{ steps.execute.outputs.cache-hit }}"
+          exit 1
+        shell: bash
+
+  regression_84_folded_block_install:
+    runs-on: ubuntu-latest
+    name: "Install multiline package listing - folded block (regression issue #84)."
+    steps:
+      - uses: actions/checkout@v4
+      - uses: ./
+        with:
+          packages: |
+            xdot \
+            rolldice distro-info-data
+          version: ${{ github.run_id }}-${{ github.run_attempt }}-regression_84_folded_block
+          debug: ${{ env.DEBUG }}
+
+  regression_84_folded_block_restore:
+    needs: regression_84_folded_block_install
+    runs-on: ubuntu-latest
+    name: "Restore multiline package listing - folded block (regression issue #84)."
+    steps:
+      - uses: actions/checkout@v4
+      - name: Execute
+        id: execute
+        uses: ./
+        with:
+          packages: xdot rolldice distro-info-data
+          version: ${{ github.run_id }}-${{ github.run_attempt }}-regression_84_folded_block
+          debug: ${{ env.DEBUG }}
+      - name: Verify
+        if: steps.execute.outputs.cache-hit != 'true'
+        run: |
+          echo "cache-hit = ${{ steps.execute.outputs.cache-hit }}"
+          exit 1
+        shell: bash
+
+  regression_89:
+    runs-on: ubuntu-latest
+    name: "Upload logs artifact name (regression issue #89)."
+    steps:
+      - uses: actions/checkout@v4
+      - uses: ./
+        with:
+          packages: libgtk-3-dev:amd64
+          version: ${{ github.run_id }}-${{ github.run_attempt }}-regression_89
+          debug: ${{ env.DEBUG }}
+
+  regression_98:
+    runs-on: ubuntu-latest
+    name: "Install error due to SHELLOPTS override (regression issue #98)."
+    steps:
+      - uses: actions/checkout@v4
+      - uses: ./
+        with:
+          packages: git-restore-mtime libgl1-mesa-dev libosmesa6-dev pandoc
+          version: ${{ github.run_id }}-${{ github.run_attempt }}-regression_98
+          debug: ${{ env.DEBUG }}
+
+  regression_106_install:
+    runs-on: ubuntu-latest
+    name: "Stale apt repo - install phase (regression issue #106)."
+    steps:
+      - uses: actions/checkout@v4
+      - uses: ./
+        with:
+          packages: libtk8.6
+          version: ${{ github.run_id }}-${{ github.run_attempt }}-regression_106
+          debug: ${{ env.DEBUG }}
+
+  regression_106_restore:
+    needs: regression_106_install
+    runs-on: ubuntu-latest
+    name: "Stale apt repo - restore phase (regression issue #106)."
+    steps:
+      - uses: actions/checkout@v4
+      - uses: ./
+        with:
+          packages: libtk8.6
+          version: ${{ github.run_id }}-${{ github.run_attempt }}-regression_106
+          debug: ${{ env.DEBUG }}
+
+  # === Special Cases ===
+
+  multi_arch_cache_key:
+    runs-on: ubuntu-latest
+    name: "Cache packages with multi-arch cache key."
+    steps:
+      - uses: actions/checkout@v4
+      - uses: ./
+        with:
+          packages: libfuse2
+          version: ${{ github.run_id }}-${{ github.run_attempt }}-multi_arch_cache_key
+          debug: ${{ env.DEBUG }}
+
+  virtual_package:
+    runs-on: ubuntu-latest
+    name: "Cache virtual package."
+    steps:
+      - uses: actions/checkout@v4
+      - uses: ./
+        with:
+          packages: libvips
+          version: ${{ github.run_id }}-${{ github.run_attempt }}-virtual_package
+          debug: ${{ env.DEBUG }}