tests_linux.yml

name: Testing (Linux)
on:
  workflow_call:
    inputs:
      lightning-version:
        type: string
        required: true
        description: The version of Lightning to use. Valid values are either 'release' (most recent release candidate), 'stable' (most recent git-tag) or 'latest' (most recent commit from master)
      pennylane-version:
        type: string
        required: true
        description: The version of PennyLane to use. Valid values are either 'release' (most recent release candidate), 'stable' (most recent git-tag) or 'latest' (most recent commit from master)
  pull_request:
  push:
    branches:
      - master

env:
  TF_VERSION: 2.10.0
  TORCH_VERSION: 1.11.0+cpu
  COVERAGE_FLAGS: "--cov=pennylane_lightning --cov-report=term-missing --no-flaky-report -p no:warnings --tb=native"
  GCC_VERSION: 11
  OMP_NUM_THREADS: "2"
  OMP_PROC_BIND: "false"

concurrency:
  group: tests_linux-${{ github.ref }}-${{ inputs.lightning-version }}-${{ inputs.pennylane-version }}
  cancel-in-progress: true

jobs:
  cpptests:
    if: ${{ !contains(fromJSON('["schedule", "workflow_dispatch"]'), github.event_name) }}
    strategy:
      matrix:
        os: [ubuntu-22.04]
        pl_backend: ["lightning_qubit"]
    timeout-minutes: 60
    name: C++ tests
    runs-on: ${{ matrix.os }}

    steps:
      - uses: actions/setup-python@v5
        name: Install Python
        with:
          python-version: '3.9'

      - name: Checkout PennyLane-Lightning
        uses: actions/checkout@v4

      - name: Install dependencies
        run: |
            echo ${{ github.event_name }} && sudo apt-get update && sudo apt-get -y -q install cmake gcc-$GCC_VERSION  g++-$GCC_VERSION ninja-build gcovr lcov
            python -m pip install scipy

      - name: Build and run unit tests
        run: |
            cmake . -BBuild -G Ninja \
              -DCMAKE_BUILD_TYPE=Debug \
              -DBUILD_TESTS=ON \
              -DENABLE_PYTHON=OFF \
              -DPL_BACKEND=${{ matrix.pl_backend }} \
              -DCMAKE_CXX_COMPILER=$(which g++-$GCC_VERSION) \
              -DENABLE_COVERAGE=ON

            cmake . -BBuildKernelOMP -G Ninja \
              -DCMAKE_BUILD_TYPE=Debug \
              -DBUILD_TESTS=ON \
              -DENABLE_PYTHON=OFF \
              -DPL_BACKEND=${{ matrix.pl_backend }} \
              -DCMAKE_CXX_COMPILER=$(which g++-$GCC_VERSION) \
              -DENABLE_COVERAGE=ON \
              -DLQ_ENABLE_KERNEL_OMP=ON

            cmake --build ./Build
            cmake --build ./BuildKernelOMP

            for d in Build BuildKernelOMP; do
              cd ./$d
              mkdir -p ./tests/results
              for file in *runner ; do ./$file --order lex --reporter junit --out ./tests/results/report_$file.xml; done;
              lcov --directory . -b ../pennylane_lightning/core/src --capture --output-file coverage.info
              lcov --remove coverage.info '/usr/*' --output-file coverage.info
              cd ..
            done
            lcov --add-tracefile ./Build/coverage.info -a ./BuildKernelOMP/coverage.info -o coverage.info
            mv coverage.info coverage-${{ github.job }}-${{ matrix.pl_backend }}.info

      - name: Upload test results
        uses: actions/upload-artifact@v3
        if: always()
        with:
          name: ubuntu-tests-reports-${{ github.job }}-${{ matrix.pl_backend }}
          path: |
            ./Build/tests/results/
            ./BuildKernelOMP/tests/results/

          if-no-files-found: error

      - name: Upload code coverage results
        uses: actions/upload-artifact@v3
        with:
          name: ubuntu-codecov-results-cpp
          path: ./coverage-${{ github.job }}-${{ matrix.pl_backend }}.info
          if-no-files-found: error

  pythontests:
    strategy:
      matrix:
        os: [ubuntu-22.04]
        pl_backend: ["lightning_qubit"]
    timeout-minutes: 60
    name: Python tests
    runs-on: ${{ matrix.os }}

    steps:
      - uses: actions/setup-python@v4
        name: Install Python
        with:
          python-version: '3.9'
          
      - name: Checkout PennyLane-Lightning
        uses: actions/checkout@v4
        with:
          fetch-tags: true
          path: main

      - name: Switch to release build of Lightning
        if: inputs.lightning-version == 'release'
        run: |
          cd main
          git fetch --all
          git checkout $(git branch -a --list "origin/v*rc*" | tail -1)

      - name: Switch to stable build of Lightning
        if: inputs.lightning-version == 'stable'
        run: |
          cd main
          git fetch --tags --force
          git checkout $(git tag | sort -V | tail -1)
          git log -1 --format='%H'
          git status

      - uses: actions/setup-python@v5
        name: Install Python
        with:
          python-version: '3.9'

      - name: Install dependencies
        run: |
          sudo apt-get update && sudo apt-get -y -q install cmake gcc-$GCC_VERSION  g++-$GCC_VERSION
          python -m pip install scipy

      - name: Get required Python packages
        run: |
          cd main
          python -m pip install -r requirements-dev.txt
          python -m pip install openfermionpyscf

      - name: Checkout PennyLane for release build
        if: inputs.pennylane-version == 'release'
        uses: actions/checkout@v4
        with:
          path: pennylane
          repository: PennyLaneAI/pennylane

      - name: Switch to release build of PennyLane
        if: inputs.pennylane-version == 'release'
        run: |
          cd pennylane
          git fetch --all
          git checkout $(git branch -a --list "origin/v*rc*" | tail -1)
          python -m pip uninstall -y pennylane && python -m pip install . -vv --no-deps

      - name: Install Stable PennyLane
        if: inputs.pennylane-version == 'stable'
        run: |
          cd main
          python -m pip uninstall -y pennylane && python -m pip install -U pennylane

      - name: Install ML libraries for interfaces
        run: |
          python -m pip install --upgrade torch==$TORCH_VERSION -f https://download.pytorch.org/whl/cpu/torch_stable.html
          python -m pip install --upgrade "jax[cpu]"  # This also installs jaxlib
          python -m pip install --upgrade tensorflow~=$TF_VERSION keras~=$TF_VERSION

      - name: Install backend device
        run: |
          cd main
          CMAKE_ARGS="-DPL_BACKEND=${{ matrix.pl_backend }} -DLQ_ENABLE_KERNEL_OMP=ON -DENABLE_PYTHON=ON -DCMAKE_CXX_COMPILER=$(which g++-$GCC_VERSION)" \
          python -m pip install -e . -vv

      - name: Run PennyLane-Lightning unit tests
        run: |
          # TODO: Remove installing pytest-xdist with release v0.36.0
          python -m pip install pytest-xdist
          cd main/
          DEVICENAME=`echo ${{ matrix.pl_backend }} | sed "s/_/./g"`
          OMP_NUM_THREADS=1 PL_DEVICE=${DEVICENAME} python -m pytest -n auto tests/ -k "not unitary_correct" $COVERAGE_FLAGS
          PL_DEVICE=${DEVICENAME} python -m pytest tests/ -k "unitary_correct" $COVERAGE_FLAGS --cov-append
          pl-device-test --device ${DEVICENAME} --skip-ops --shots=20000 $COVERAGE_FLAGS --cov-append
          pl-device-test --device ${DEVICENAME} --shots=None --skip-ops $COVERAGE_FLAGS --cov-append
          mv .coverage .coverage-${{ github.job }}-${{ matrix.pl_backend }}

      - name: Upload code coverage results
        uses: actions/upload-artifact@v3
        with:
          name: ubuntu-codecov-results-python
          path: |
            ./main/.coverage-${{ github.job }}-${{ matrix.pl_backend }}
          if-no-files-found: error

  cpptestswithOpenBLAS:
    if: ${{ !contains(fromJSON('["schedule", "workflow_dispatch"]'), github.event_name) }}
    strategy:
      matrix:
        os: [ubuntu-22.04]
        pl_backend: ["lightning_qubit"]
    timeout-minutes: 60
    name: C++ tests (OpenBLAS)
    runs-on: ${{ matrix.os }}

    steps:
      - uses: actions/setup-python@v5
        name: Install Python
        with:
          python-version: '3.9'

      - name: Checkout PennyLane-Lightning
        uses: actions/checkout@v4

      - name: Install dependencies
        run: |
          sudo apt-get update && sudo apt-get -y -q install cmake gcc-$GCC_VERSION  g++-$GCC_VERSION libopenblas-dev ninja-build gcovr lcov
          python -m pip install scipy

      - name: Build and run unit tests
        run: |
            cmake . -BBuild -G Ninja \
              -DCMAKE_BUILD_TYPE=Debug \
              -DENABLE_PYTHON=OFF \
              -DENABLE_BLAS=ON \
              -DPL_BACKEND=${{ matrix.pl_backend }} \
              -DBUILD_TESTS=ON \
              -DCMAKE_CXX_COMPILER=$(which g++-$GCC_VERSION) \
              -DENABLE_COVERAGE=ON
            cmake --build ./Build
            cd ./Build
            mkdir -p ./tests/results
            for file in *runner ; do ./$file --order lex --reporter junit --out ./tests/results/report_$file.xml; done;
            lcov --directory . -b ../pennylane_lightning/core/src --capture --output-file coverage.info
            lcov --remove coverage.info '/usr/*' --output-file coverage.info
            mv coverage.info coverage-${{ github.job }}-${{ matrix.pl_backend }}.info

      - name: Upload test results
        uses: actions/upload-artifact@v3
        if: always()
        with:
          name: ubuntu-tests-reports-${{ github.job }}-${{ matrix.pl_backend }}
          path: ./Build/tests/results/
          if-no-files-found: error

      - name: Upload code coverage results
        uses: actions/upload-artifact@v3
        with:
          name: ubuntu-codecov-results-cpp
          path: ./Build/coverage-${{ github.job }}-${{ matrix.pl_backend }}.info
          if-no-files-found: error

  pythontestswithOpenBLAS:
    strategy:
      matrix:
        os: [ubuntu-22.04]
        pl_backend: ["lightning_qubit"]
    timeout-minutes: 60
    name: Python tests with OpenBLAS
    runs-on: ${{ matrix.os }}

    steps:
      - name: Checkout PennyLane-Lightning
        uses: actions/checkout@v4
        with:
          fetch-tags: true
          path: main

      - name: Switch to release build of Lightning
        if: inputs.lightning-version == 'release'
        run: |
          cd main
          git fetch --all
          git checkout $(git branch -a --list "origin/v*rc*" | tail -1)

      - name: Switch to stable build of Lightning
        if: inputs.lightning-version == 'stable'
        run: |
          cd main
          git fetch --tags --force
          git checkout $(git tag | sort -V | tail -1)
          git log -1 --format='%H'
          git status

      - uses: actions/setup-python@v5
        name: Install Python
        with:
          python-version: '3.9'

      - name: Install dependencies
        run: |
          sudo apt-get update && sudo apt-get -y -q install cmake gcc-$GCC_VERSION  g++-$GCC_VERSION  libopenblas-dev
          python -m pip install scipy

      - name: Get required Python packages
        run: |
          cd main
          python -m pip install -r requirements-dev.txt
          python -m pip install openfermionpyscf

      - name: Checkout PennyLane for release build
        if: inputs.pennylane-version == 'release'
        uses: actions/checkout@v4
        with:
          path: pennylane
          repository: PennyLaneAI/pennylane

      - name: Switch to release build of PennyLane
        if: inputs.pennylane-version == 'release'
        run: |
          cd pennylane
          git fetch --all
          git checkout $(git branch -a --list "origin/v*rc*" | tail -1)
          python -m pip uninstall -y pennylane && python -m pip install . -vv --no-deps

      - name: Install Stable PennyLane
        if: inputs.pennylane-version == 'stable'
        run: |
          cd main
          python -m pip uninstall -y pennylane && python -m pip install -U pennylane

      - name: Install ML libraries for interfaces
        run: |
          python -m pip install --upgrade torch==$TORCH_VERSION -f https://download.pytorch.org/whl/cpu/torch_stable.html
          python -m pip install --upgrade "jax[cpu]"  # This also installs jaxlib
          python -m pip install --upgrade tensorflow~=$TF_VERSION keras~=$TF_VERSION

      - name: Install backend device
        run: |
          cd main
          python -m pip install scipy
          CMAKE_ARGS="-DPL_BACKEND=${{ matrix.pl_backend }} -DENABLE_BLAS=ON -DENABLE_PYTHON=ON -DCMAKE_CXX_COMPILER=$(which g++-$GCC_VERSION)" \
          python -m pip install -e . -vv

      - name: Run PennyLane-Lightning unit tests
        run: |
          # TODO: Remove installing pytest-xdist with release v0.36.0
          python -m pip install pytest-xdist
          cd main/
          DEVICENAME=`echo ${{ matrix.pl_backend }} | sed "s/_/./g"`
          OMP_NUM_THREADS=1 PL_DEVICE=${DEVICENAME} python -m pytest -n auto tests/ -k "not unitary_correct and not test_native_mcm" $COVERAGE_FLAGS
          PL_DEVICE=${DEVICENAME} python -m pytest tests/ -k "unitary_correct and not test_native_mcm" $COVERAGE_FLAGS --cov-append
          pl-device-test --device ${DEVICENAME} --skip-ops --shots=20000 $COVERAGE_FLAGS --cov-append
          pl-device-test --device ${DEVICENAME} --shots=None --skip-ops $COVERAGE_FLAGS --cov-append
          mv .coverage .coverage-${{ github.job }}-${{ matrix.pl_backend }}

      - name: Upload code coverage results
        uses: actions/upload-artifact@v3
        with:
          name: ubuntu-codecov-results-python
          path: ./main/.coverage-${{ github.job }}-${{ matrix.pl_backend }}
          if-no-files-found: error

  build_and_cache_Kokkos:
    name: "Build and cache Kokkos"
    uses: ./.github/workflows/build_and_cache_Kokkos_linux.yml
    with:
      os: ubuntu-22.04

  cpptestswithKokkos:
    if: ${{ !contains(fromJSON('["schedule", "workflow_dispatch"]'), github.event_name) }}
    needs: [build_and_cache_Kokkos]
    strategy:
      matrix:
        os: [ubuntu-22.04]
        pl_backend: ["lightning_kokkos"]
        exec_model: ${{ fromJson(needs.build_and_cache_Kokkos.outputs.exec_model) }}
        kokkos_version: ${{ fromJson(needs.build_and_cache_Kokkos.outputs.kokkos_version) }}
    timeout-minutes: 60
    name: C++ tests (Kokkos)
    runs-on: ${{ matrix.os }}

    steps:
      - uses: actions/setup-python@v5
        name: Install Python
        with:
          python-version: '3.9'

      - name: Checkout PennyLane-Lightning
        uses: actions/checkout@v4

      - name: Restoring cached dependencies
        id: kokkos-cache
        uses: actions/cache@v4
        with:
          path: ${{ github.workspace}}/Kokkos_install/${{ matrix.exec_model }}
          key: ${{ matrix.os }}-kokkos${{ matrix.kokkos_version }}-${{ matrix.exec_model }}

      - name: Copy cached libraries
        if: steps.kokkos-cache.outputs.cache-hit == 'true'
        run: |
          rm -rf Kokkos
          mkdir Kokkos/
          cp -rf ${{ github.workspace}}/Kokkos_install/${{ matrix.exec_model }}/* Kokkos/

      - name: Install dependencies
        run: |
          sudo apt-get update && sudo apt-get -y -q install cmake gcc-$GCC_VERSION  g++-$GCC_VERSION ninja-build gcovr lcov
          python -m pip install scipy

      - name: Build and run unit tests
        run: |
            cmake . -BBuild -G Ninja \
              -DCMAKE_BUILD_TYPE=Debug \
              -DBUILD_TESTS=ON \
              -DENABLE_PYTHON=OFF \
              -DCMAKE_PREFIX_PATH=${{ github.workspace }}/Kokkos \
              -DPL_BACKEND=${{ matrix.pl_backend }} \
              -DCMAKE_CXX_COMPILER=$(which g++-$GCC_VERSION) \
              -DENABLE_COVERAGE=ON
            cmake --build ./Build
            cd ./Build
            mkdir -p ./tests/results_${{ github.job }}_${{ matrix.pl_backend }}
            for file in *runner ; do ./$file --order lex --reporter junit --out ./tests/results_${{ github.job }}_${{ matrix.pl_backend }}/report_$file.xml; done;
            lcov --directory . -b ../pennylane_lightning/core/src --capture --output-file coverage.info
            lcov --remove coverage.info '/usr/*' --output-file coverage.info
            mv coverage.info coverage-${{ github.job }}-${{ matrix.pl_backend }}.info

      - name: Upload test results
        uses: actions/upload-artifact@v3
        if: always()
        with:
          name: ubuntu-tests-reports-${{ github.job }}_${{ matrix.pl_backend }}
          path: ./Build/tests/results_${{ github.job }}_${{ matrix.pl_backend }}
          if-no-files-found: error

      - name: Upload code coverage results
        uses: actions/upload-artifact@v3
        with:
          name: ubuntu-codecov-results-cpp
          path: ./Build/coverage-${{ github.job }}-${{ matrix.pl_backend }}.info
          if-no-files-found: error

  pythontestswithKokkos:
    needs: [build_and_cache_Kokkos]
    strategy:
      matrix:
        os: [ubuntu-22.04]
        pl_backend: ["lightning_kokkos", "all"]
        exec_model: ${{ fromJson(needs.build_and_cache_Kokkos.outputs.exec_model) }}
        kokkos_version: ${{ fromJson(needs.build_and_cache_Kokkos.outputs.kokkos_version) }}
        exclude:
          - pl_backend: ["all"]
            exec_model: OPENMP
    timeout-minutes: 60
    name: Python tests with Kokkos
    runs-on: ${{ matrix.os }}

    steps:
      - name: Checkout PennyLane-Lightning
        uses: actions/checkout@v4
        with:
          fetch-tags: true
          path: main

      - name: Switch to release build of Lightning
        if: inputs.lightning-version == 'release'
        run: |
          cd main
          git fetch --all
          git checkout $(git branch -a --list "origin/v*rc*" | tail -1)

      - name: Switch to stable build of Lightning
        if: inputs.lightning-version == 'stable'
        run: |
          cd main
          git fetch --tags --force
          git checkout $(git tag | sort -V | tail -1)
          git log -1 --format='%H'
          git status

      - uses: actions/setup-python@v5
        name: Install Python
        with:
          python-version: '3.9'

      - name: Restoring cached dependencies
        id: kokkos-cache
        uses: actions/cache@v4
        with:
          path: ${{ github.workspace}}/Kokkos_install/${{ matrix.exec_model }}
          key: ${{ matrix.os }}-kokkos${{ matrix.kokkos_version }}-${{ matrix.exec_model }}

      - name: Copy cached libraries
        if: steps.kokkos-cache.outputs.cache-hit == 'true'
        run: |
          rm -rf Kokkos
          mkdir Kokkos/
          cp -rf ${{ github.workspace}}/Kokkos_install/${{ matrix.exec_model }}/* Kokkos/
          pwd

      - name: Install dependencies
        run: |
          sudo apt-get update && sudo apt-get -y -q install cmake gcc-$GCC_VERSION  g++-$GCC_VERSION
          python -m pip install scipy

      - name: Get required Python packages
        run: |
          cd main
          python -m pip install -r requirements-dev.txt
          python -m pip install openfermionpyscf

      - name: Checkout PennyLane for release build
        if: inputs.pennylane-version == 'release'
        uses: actions/checkout@v4
        with:
          path: pennylane
          repository: PennyLaneAI/pennylane

      - name: Switch to release build of PennyLane
        if: inputs.pennylane-version == 'release'
        run: |
          cd pennylane
          git fetch --all
          git checkout $(git branch -a --list "origin/v*rc*" | tail -1)
          python -m pip uninstall -y pennylane && python -m pip install . -vv --no-deps

      - name: Install Stable PennyLane
        if: inputs.pennylane-version == 'stable'
        run: |
          cd main
          python -m pip uninstall -y pennylane && python -m pip install -U pennylane

      - name: Install ML libraries for interfaces
        run: |
          python -m pip install --upgrade torch==$TORCH_VERSION -f https://download.pytorch.org/whl/cpu/torch_stable.html
          python -m pip install --upgrade "jax[cpu]"  # This also installs jaxlib
          python -m pip install --upgrade tensorflow~=$TF_VERSION keras~=$TF_VERSION

      - name: Install backend device
        if: ${{ matrix.pl_backend != 'all'}}
        run: |
          cd main
          python -m pip install scipy
          SKIP_COMPILATION=True PL_BACKEND="lightning_qubit" pip install -e . -vv
          CMAKE_ARGS="-DPL_BACKEND=${{ matrix.pl_backend }} -DCMAKE_PREFIX_PATH=${{ github.workspace }}/Kokkos -DENABLE_PYTHON=ON -DCMAKE_CXX_COMPILER=$(which g++-$GCC_VERSION)" \
          python -m pip install -e . -vv

      - name: Run PennyLane-Lightning unit tests
        if: ${{ matrix.pl_backend != 'all'}}
        run: |
          # TODO: Remove installing pytest-xdist with release v0.36.0
          python -m pip install pytest-xdist
          cd main/
          DEVICENAME=`echo ${{ matrix.pl_backend }} | sed "s/_/./g"`
          PL_DEVICE=${DEVICENAME} python -m pytest tests/ -k "not test_native_mcm" $COVERAGE_FLAGS
          pl-device-test --device ${DEVICENAME} --skip-ops --shots=20000 $COVERAGE_FLAGS --cov-append
          pl-device-test --device ${DEVICENAME} --shots=None --skip-ops $COVERAGE_FLAGS --cov-append
          mv .coverage .coverage-${{ github.job }}-${{ matrix.pl_backend }}
          # TODO: Remove this if-cond with release v0.36.0
          if [ -f tests/test_native_mcm.py ]; then
              OMP_NUM_THREADS=1 PL_DEVICE=${DEVICENAME} python -m pytest -n auto tests/ -k "test_native_mcm" $COVERAGE_FLAGS --cov-append
          fi

      - name: Install all backend devices
        if: ${{ matrix.pl_backend == 'all' }}
        run: |
          cd main
          CMAKE_ARGS="-DPL_BACKEND="lightning_qubit" -DCMAKE_PREFIX_PATH=${{ github.workspace }}/Kokkos -DENABLE_PYTHON=ON -DCMAKE_CXX_COMPILER=$(which g++-$GCC_VERSION)" \
          python -m pip install -e . -vv
          rm -rf build
          CMAKE_ARGS="-DPL_BACKEND="lightning_kokkos" -DCMAKE_PREFIX_PATH=${{ github.workspace }}/Kokkos -DENABLE_PYTHON=ON -DCMAKE_CXX_COMPILER=$(which g++-$GCC_VERSION)" \
          python -m pip install -e . -vv

      - name: Run PennyLane-Lightning unit tests for lightning.qubit with all devices installed
        if: ${{ matrix.pl_backend == 'all' }}
        run: |
          # TODO: Remove installing pytest-xdist with release v0.36.0
          python -m pip install pytest-xdist
          cd main/
          OMP_NUM_THREADS=1 PL_DEVICE=lightning.qubit python -m pytest -n auto tests/ -k "not unitary_correct and not test_native_mcm" $COVERAGE_FLAGS
          PL_DEVICE=lightning.qubit python -m pytest tests/ -k "unitary_correct and not test_native_mcm" $COVERAGE_FLAGS --cov-append
          pl-device-test --device lightning.qubit --skip-ops --shots=20000 $COVERAGE_FLAGS --cov-append
          pl-device-test --device lightning.qubit --shots=None --skip-ops $COVERAGE_FLAGS --cov-append
          PL_DEVICE=lightning.kokkos python -m pytest tests/ -k "not test_native_mcm" $COVERAGE_FLAGS --cov-append
          pl-device-test --device lightning.kokkos --skip-ops --shots=20000 $COVERAGE_FLAGS --cov-append
          pl-device-test --device lightning.kokkos --shots=None --skip-ops $COVERAGE_FLAGS --cov-append
          mv .coverage .coverage-${{ github.job }}-${{ matrix.pl_backend }}

      - name: Upload code coverage results
        uses: actions/upload-artifact@v3
        with:
          name: ubuntu-codecov-results-python
          path: ./main/.coverage-${{ github.job }}-${{ matrix.pl_backend }}
          if-no-files-found: error

  upload-to-codecov-linux-python:
    needs: [pythontests, pythontestswithOpenBLAS, pythontestswithKokkos]
    name: Upload python coverage data to codecov
    runs-on: ubuntu-latest
    steps:
      - name: Checkout
        uses: actions/checkout@v4
        with:
          fetch-tags: true
          path: main

      - name: Download coverage reports
        uses: actions/download-artifact@v3
        with:
          name: ubuntu-codecov-results-python

      - name: Combine coverage files
        run: |
          python -m pip install coverage
          python -m coverage combine .coverage-python*
          # Added cov xml -i to ignore "No source for code" random errors
          # https://stackoverflow.com/questions/2386975/no-source-for-code-message-in-coverage-py
          python -m coverage xml -i -o coverage-${{ github.job }}.xml

      - name: Upload to Codecov
        uses: codecov/codecov-action@v4
        with:
          fail_ci_if_error: true
          verbose: true
          token: ${{ secrets.CODECOV_TOKEN }}

  upload-to-codecov-linux-cpp:
    needs: [cpptests, cpptestswithOpenBLAS, cpptestswithKokkos]
    name: Upload cpp coverage data to codecov
    runs-on: ubuntu-latest
    steps:
      - name: Checkout
        uses: actions/checkout@v4

      - name: Download coverage reports
        uses: actions/download-artifact@v3
        with:
          name: ubuntu-codecov-results-cpp

      - name: Upload to Codecov
        uses: codecov/codecov-action@v4
        with:
          fail_ci_if_error: true
          verbose: true
          token: ${{ secrets.CODECOV_TOKEN }}

  cpptestsWithMultipleBackends:
  # Device-specific tests are performed for both. Device-agnostic tests default to LightningQubit.
    if: ${{ !contains(fromJSON('["schedule", "workflow_dispatch"]'), github.event_name) }}
    needs: [build_and_cache_Kokkos]
    strategy:
      matrix:
        os: [ubuntu-22.04]
        exec_model: ${{ fromJson(needs.build_and_cache_Kokkos.outputs.exec_model) }}
        kokkos_version: ${{ fromJson(needs.build_and_cache_Kokkos.outputs.kokkos_version) }}
    timeout-minutes: 60
    name: C++ tests (multiple backends)
    runs-on: ${{ matrix.os }}

    steps:
      - uses: actions/setup-python@v5
        name: Install Python
        with:
          python-version: '3.9'

      - name: Checkout PennyLane-Lightning
        uses: actions/checkout@v4

      - name: Restoring cached dependencies
        id: kokkos-cache
        uses: actions/cache@v4
        with:
          path: ${{ github.workspace}}/Kokkos_install/${{ matrix.exec_model }}
          key: ${{ matrix.os }}-kokkos${{ matrix.kokkos_version }}-${{ matrix.exec_model }}

      - name: Copy cached libraries
        if: steps.kokkos-cache.outputs.cache-hit == 'true'
        run: |
          rm -rf Kokkos
          mkdir Kokkos/
          cp -rf ${{ github.workspace}}/Kokkos_install/${{ matrix.exec_model }}/* Kokkos/

      - name: Install dependencies
        run: |
          sudo apt-get update && sudo apt-get -y -q install cmake gcc-$GCC_VERSION  g++-$GCC_VERSION ninja-build gcovr lcov
          python -m pip install scipy

      - name: Build and run unit tests
        run: |
            set -x
            cmake . -BBuild -G Ninja \
              -DCMAKE_BUILD_TYPE=Debug \
              -DBUILD_TESTS=ON \
              -DENABLE_PYTHON=OFF \
              -DCMAKE_PREFIX_PATH=${{ github.workspace }}/Kokkos \
              -DPL_BACKEND="lightning_qubit;lightning_kokkos" \
              -DCMAKE_CXX_COMPILER=$(which g++-$GCC_VERSION)
            cmake --build ./Build
            cd ./Build
            mkdir -p ./tests/results_multiple_backends
            for file in *runner ; do ./$file --order lex --reporter junit --out ./tests/results_multiple_backends/report_$file.xml; done;
            set +x

      - name: Upload test results
        uses: actions/upload-artifact@v3
        if: always()
        with:
          name: ubuntu-tests-reports-${{ github.job }}-multiple-backends
          path: ./Build/tests/results_multiple_backends/
          if-no-files-found: error