Merge mg5amcnlo 3.7.3 and madspin_density into main

.github/actions/restore-pip-cache/action.yml

@@ -17,6 +17,19 @@ runs:
         sudo apt install meson ninja-build
         echo "PYTHONPATH=$PYTHONPATH:$HOME/.cache/pip-packages" >> $GITHUB_ENV
         echo "$HOME/.cache/pip-packages/bin" >> $GITHUB_PATH
+        # Install meson+ninja if missing (numpy 2.x f2py requires meson as build backend).
+        # --upgrade is needed so pip writes scripts into the existing bin/ directory;
+        # it only affects meson/ninja since numpy is not listed here.
+        if [ ! -x "$HOME/.cache/pip-packages/bin/meson" ]; then
+          pip install --target "$HOME/.cache/pip-packages" --upgrade meson ninja
+        fi
         cd $GITHUB_WORKSPACE
-        echo "f2py_compiler = $(which f2py)" >> input/mg5_configuration.txt
+        # Use direct path because GITHUB_PATH additions don't take effect in the same step
+        F2PY_BIN="$HOME/.cache/pip-packages/bin/f2py"
+        if [ -x "$F2PY_BIN" ]; then
+          echo "f2py_compiler = $F2PY_BIN" >> input/mg5_configuration.txt
+        else
+          pip install --target "$HOME/.cache/pip-packages" --upgrade numpy
+          echo "f2py_compiler = $F2PY_BIN" >> input/mg5_configuration.txt
+        fi
       shell: bash

.github/actions/restore_delphes/action.yml

@@ -0,0 +1,36 @@
+name: Restore Delphes cache
+description: Restores Delphes (and its ROOT dependency) from a dedicated cache and configures MG5
+
+# Delphes depends only on ROOT. Both live in the dedicated ~/.cache/Delphes
+# cache (kept separate from HEPtools); the delphes-<os> cache is stacked on top
+# of the root-<os> one, exactly like the HEPtools sub-caches.
+
+inputs:
+  setup_only:
+    required: false
+    default: "false"
+
+runs:
+  using: composite
+  steps:
+    # Ensure the ROOT environment (ROOTSYS/PATH/LD_LIBRARY_PATH) is set up,
+    # restoring the root cache only if a higher level did not already do so.
+    - name: restore ROOT
+      uses: ./.github/actions/restore_root
+      with:
+        setup_only: ${{ inputs.setup_only }}
+
+    - name: Set cache key
+      run: echo "CACHE_KEY=delphes-$ImageOS" >> $GITHUB_ENV
+      shell: bash
+
+    - uses: actions/cache/restore@v5
+      if: ${{ inputs.setup_only != 'true' }}
+      with:
+        path: ~/.cache/Delphes
+        key: ${{ env.CACHE_KEY }}
+
+    - run: |
+        cd $GITHUB_WORKSPACE
+        echo "delphes_path = $HOME/.cache/Delphes/Delphes" >> input/mg5_configuration.txt
+      shell: bash

.github/actions/restore_root/action.yml

@@ -0,0 +1,84 @@
+name: Restore ROOT cache
+description: Restores ROOT from its dedicated cache (separate from HEPtools) and sets ROOTSYS
+
+# ROOT and Delphes are kept in their own cache (~/.cache/Delphes) on purpose:
+# they are large and rarely change, so they should not be bundled with - nor
+# invalidated together with - the HEPtools cache. They are warmed and cleaned
+# independently (see the root_cache/delphes_cache jobs and the reset_delphes
+# input of warm_cache.yml).
+
+inputs:
+  setup_only:
+    required: false
+    default: "false"
+
+runs:
+  using: composite
+  steps:
+    - name: Set cache key
+      run: echo "CACHE_KEY=root-$ImageOS" >> $GITHUB_ENV
+      shell: bash
+
+    - name: Restore ROOT cache
+      id: cache
+      if: ${{ inputs.setup_only != 'true' }}
+      uses: actions/cache/restore@v5
+      with:
+        path: ~/.cache/Delphes
+        key: ${{ env.CACHE_KEY }}
+
+    # ROOT (6.40 binaries) links against Intel TBB at build- and run-time. The
+    # apt packages are not part of the cache, so install the runtime dependency
+    # wherever ROOT is used (Delphes build and the Delphes test jobs). The
+    # ldconfig guard makes this a no-op on images that already ship it (e.g.
+    # ubuntu-22.04); ubuntu-24.04 needs it (rootcint fails on libtbb.so.12).
+    - name: Install ROOT runtime dependencies
+      run: |
+        if ! ldconfig -p | grep -q 'libtbb\.so\.12'; then
+          sudo apt-get update
+          sudo apt-get install -y --no-install-recommends libtbb12
+        fi
+      shell: bash
+
+    # Self-heal on a cache miss instead of silently configuring a non-existent
+    # ROOTSYS: when this level is the one responsible for restoring ROOT
+    # (setup_only != true) and the cache was not found, install ROOT inline,
+    # exactly like the root_cache warm job. Keep ROOT_VERSION / the tarball
+    # names in sync with the root_cache job in warm_cache.yml.
+    - name: Install ROOT (cache miss fallback)
+      if: ${{ inputs.setup_only != 'true' && steps.cache.outputs.cache-hit != 'true' }}
+      run: |
+        echo "::warning::ROOT cache miss for ${CACHE_KEY}; installing ROOT inline."
+        ROOT_VERSION=6.40.02
+        case "$ImageOS" in
+          ubuntu22) ROOT_TARBALL=root_v${ROOT_VERSION}.Linux-ubuntu22.04-x86_64-gcc11.4.tar.gz ;;
+          ubuntu24) ROOT_TARBALL=root_v${ROOT_VERSION}.Linux-ubuntu24.04-x86_64-gcc13.3.tar.gz ;;
+          *) echo "Unsupported runner image: $ImageOS"; exit 1 ;;
+        esac
+        mkdir -p "$HOME/.cache/Delphes"
+        cd "$HOME/.cache/Delphes"
+        rm -rf root
+        wget -q "https://root.cern/download/${ROOT_TARBALL}"
+        tar -xzf "${ROOT_TARBALL}"
+        rm -f "${ROOT_TARBALL}"
+      shell: bash
+
+    - name: Configure ROOT environment
+      run: |
+        echo "ROOTSYS=$HOME/.cache/Delphes/root" >> $GITHUB_ENV
+        echo "$HOME/.cache/Delphes/root/bin" >> $GITHUB_PATH
+        echo "LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$HOME/.cache/Delphes/root/lib" >> $GITHUB_ENV
+        echo "PYTHONPATH=$PYTHONPATH:$HOME/.cache/Delphes/root/lib" >> $GITHUB_ENV
+      shell: bash
+
+    # Fail fast (only when this level is responsible for ROOT) if ROOT is still
+    # missing after restore + fallback install, rather than letting downstream
+    # steps run against a non-existent ROOTSYS.
+    - name: Verify ROOT is available
+      if: ${{ inputs.setup_only != 'true' }}
+      run: |
+        if [ ! -x "$HOME/.cache/Delphes/root/bin/root-config" ]; then
+          echo "::error::ROOT is not available at $HOME/.cache/Delphes/root after restore/install."
+          exit 1
+        fi
+      shell: bash