fixup! fix(ci): latex caching improvements

Signed-off-by: skjnldsv <skjnldsv@protonmail.com>

Author: skjnldsv

.github/workflows/sphinxbuild.yml

@@ -11,10 +11,43 @@ permissions:
   contents: read
 
 jobs:
+  setup-latex-cache:
+    name: Cache LaTeX packages
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: Configure apt cache
+      run: |
+        mkdir -p /tmp/apt/cache/archives
+        echo 'Dir::Cache::archives "/tmp/apt/cache/archives";' | sudo tee /etc/apt/apt.conf.d/apt-cache-tmp
+
+    - name: Cache LaTeX apt packages
+      id: cache-latex-apt
+      uses: actions/cache@668228422ae6a00e4ad889ee87cd7109ec5666a7 # v5.0.4
+      with:
+        path: /tmp/apt/cache/archives
+        key: latex-apt-${{ runner.os }}-${{ runner.arch }}-ubuntu-24.04-texlive-2023
+        restore-keys: |
+          latex-apt-${{ runner.os }}-${{ runner.arch }}-ubuntu-24.04-
+          latex-apt-${{ runner.os }}-${{ runner.arch }}-
+
+    - name: Download LaTeX packages (cache miss only)
+      if: steps.cache-latex-apt.outputs.cache-hit != 'true'
+      run: |
+        sudo DEBIAN_FRONTEND=noninteractive apt-get update
+        sudo DEBIAN_FRONTEND=noninteractive apt-get install -y --no-install-recommends \
+          --download-only \
+          python3-pil python3-pip texlive-fonts-recommended latexmk \
+          texlive-latex-extra texlive-latex-recommended texlive-xetex \
+          texlive-fonts-extra-links texlive-fonts-extra xindy
+        # Ensure downloaded packages are owned by the current user so they can be cached
+        sudo chown -R $(id -u):$(id -g) /tmp/apt/cache/archives
+
   build:
 
     name: Build ${{ matrix.manual.name }}
     runs-on: ubuntu-latest
+    needs: setup-latex-cache
 
     strategy:
       matrix:
@@ -72,28 +105,18 @@ jobs:
         mkdir -p /tmp/apt/cache/archives
         echo 'Dir::Cache::archives "/tmp/apt/cache/archives";' | sudo tee /etc/apt/apt.conf.d/apt-cache-tmp
 
-    - name: Cache LaTeX apt packages
+    - name: Restore LaTeX apt cache
       if: ${{ matrix.manual.build_pdf_path }}
-      id: cache-latex-apt
-      uses: actions/cache@668228422ae6a00e4ad889ee87cd7109ec5666a7 # v5.0.4
+      uses: actions/cache/restore@668228422ae6a00e4ad889ee87cd7109ec5666a7 # v5.0.4
       with:
         path: /tmp/apt/cache/archives
         key: latex-apt-${{ runner.os }}-${{ runner.arch }}-ubuntu-24.04-texlive-2023
         restore-keys: |
           latex-apt-${{ runner.os }}-${{ runner.arch }}-ubuntu-24.04-
           latex-apt-${{ runner.os }}-${{ runner.arch }}-
 
-    - name: Install LaTeX dependencies
-      if: ${{ matrix.manual.build_pdf_path && steps.cache-latex-apt.outputs.cache-hit != 'true' }}
-      run: |
-        sudo DEBIAN_FRONTEND=noninteractive apt-get update
-        sudo DEBIAN_FRONTEND=noninteractive apt-get install -y --no-install-recommends \
-          python3-pil python3-pip texlive-fonts-recommended latexmk \
-          texlive-latex-extra texlive-latex-recommended texlive-xetex \
-          texlive-fonts-extra-links texlive-fonts-extra xindy
-
     - name: Install LaTeX from cache
-      if: ${{ matrix.manual.build_pdf_path && steps.cache-latex-apt.outputs.cache-hit == 'true' }}
+      if: ${{ matrix.manual.build_pdf_path }}
       run: |
         sudo DEBIAN_FRONTEND=noninteractive apt-get update
         sudo DEBIAN_FRONTEND=noninteractive apt-get install -y --no-install-recommends \
@@ -102,10 +125,6 @@ jobs:
           texlive-latex-extra texlive-latex-recommended texlive-xetex \
           texlive-fonts-extra-links texlive-fonts-extra xindy
 
-    - name: Fix apt cache ownership
-      if: ${{ matrix.manual.build_pdf_path && steps.cache-latex-apt.outputs.cache-hit != 'true' }}
-      run: sudo chown -R $(id -u):$(id -g) /tmp/apt/cache/archives
-
     - name: Build html documentation
       run: cd ${{ matrix.manual.directory }} && make ${{ matrix.manual.make_target }}