Minimal cache experiment

.github/workflows/cache-minimal.yml

@@ -0,0 +1,72 @@
+# Test minimal save/restore of a cache
+
+name: Minimal cache test
+
+on:
+  push:
+    branches:
+      - disabled
+
+jobs:
+  minimal-cache:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Create fake data
+        run: |
+          mkdir data1
+          mkdir data2
+          touch data1/thedata.txt
+          touch data2/thedata.txt
+
+      - name: Create unique key
+        id: cache-key
+        run: |
+          echo "key=cache test $(date -u)" >> $GITHUB_OUTPUT
+
+      - name: Verify cache miss
+        id: miss
+        uses: actions/cache/restore@v4
+        with:
+          path: |
+            data1
+            data2
+          key: ${{ steps.cache-key.outputs.key }}
+          lookup-only: true
+
+      - name: Save cache
+        uses: actions/cache/save@v4
+        with:
+          path: |
+            data1
+            data2
+          key: ${{ steps.cache-key.outputs.key }}
+
+      - name: Query cache hit 1
+        id: hit1
+        uses: actions/cache/restore@v4
+        with:
+          path: |
+            data1
+            data2
+          key: ${{ steps.cache-key.outputs.key }}
+          fail-on-cache-miss: false
+          lookup-only: true
+
+      # NOTE inverted path order
+      - name: Query cache hit 2
+        id: hit2
+        uses: actions/cache/restore@v4
+        with:
+          path: |
+            data2
+            data1
+          key: ${{ steps.cache-key.outputs.key }}
+          fail-on-cache-miss: false
+          lookup-only: true
+
+      - name: Print both cache hit and miss
+        run: |
+          echo "Cache miss? ${{ steps.miss.outputs.cache-hit }}"
+          echo "Cache hit 1? ${{ steps.hit1.outputs.cache-hit }}"
+          echo "Cache hit 2? ${{ steps.hit2.outputs.cache-hit }}"

.github/workflows/selftest.yml

@@ -4,7 +4,10 @@
 
 name: Selftest
 
-on: pull_request
+on:
+  pull_request:
+    # branches:
+    #   - disabled
 
 jobs:
   setup-alire:

.github/workflows/test-cache.yml

@@ -6,13 +6,18 @@ name: Test cache
 
 on:
   pull_request:
+    # branches:
+    #   - disabled
 
 jobs:
   test-cache:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-latest, macos-latest, windows-latest]
+        os:
+          - macos-latest
+          - ubuntu-latest
+          - windows-latest
         config:
           - version: '2.0.1'
             branch:  ''

action.yml

@@ -24,7 +24,7 @@ inputs:
 outputs:
   cache_hit:
     description: Whether a cached installation was reused
-    value: ${{ steps.cache-alr.outputs.cache-hit }}
+    value: ${{ steps.cache-output.outputs.cache_hit }}
 
 runs:
   using: "composite"
@@ -50,7 +50,7 @@ runs:
       id: cache-key
       shell: bash
       run: |
-        echo "key=alr[${{ steps.find-hash.outputs.version }}][${{ inputs.toolchain }}][${{ runner.os }}][${{ steps.find-hash.outputs.hash }}][c]" >> $GITHUB_OUTPUT
+        echo "key=alr[${{ steps.find-hash.outputs.version }}][${{ inputs.toolchain }}][${{ runner.os }}][${{ steps.find-hash.outputs.hash }}][f]" >> $GITHUB_OUTPUT
       # The last value in square brackets is to make the key unique for debugging
 
     - name: Reuse cached installation
@@ -61,21 +61,33 @@ runs:
         path: |
           ~/.cache/alire
           ~/.config/alire
-          ./alire_install
           ~/.local/share/alire
+          ./alire_install
           ~/AppData/Local/alire
-        key: ${{steps.cache-key.outputs.key}}
         # .cache contains msys64 install on Windows
         # .config contains the toolchain at the default location, besides index config
         # ./alire_install contains alr itself
         # ~/AppData and ./local/share/alire is used with Alire 2.0 onwards
         # Note that '~' is recommended on Windows too: https://github.com/actions/cache
+        # THESE MUST BE EXACTLY THE SAME IN SAME ORDER IN ALL CACHE-RELATED STEPS
+        key: ${{steps.cache-key.outputs.key}}
 
     - name: Check cache output
       shell: bash
       run: |
         echo Cache hit result: [${{steps.cache-alr.outputs.cache-hit}}] cache-key: ${{steps.cache-key.outputs.key}}
 
+    # In case of miss, give an explicit 'false' which actions/cache doesn't provide
+    - name: Set cache_hit to false if needed
+      id: cache-output
+      shell: bash
+      run: |
+        if [[ "${{inputs.cache}}" == "true" && "${{steps.cache-alr.outputs.cache-hit}}" == "true" ]]; then
+          echo "cache_hit=true" >> $GITHUB_OUTPUT
+        else
+          echo "cache_hit=false" >> $GITHUB_OUTPUT
+        fi
+
     # Ascertain if we need to install a toolchain for building from sources
     - name: Find GNAT
       shell: bash
@@ -181,17 +193,20 @@ runs:
           ~/.local/share/alire
           ./alire_install
           ~/AppData/Local/alire
-        key: ${{ steps.cache-alr.outputs.cache-primary-key }}
-        # Note that '~' is recommended on Windows too:
-        # https://github.com/actions/cache
+        key: ${{ steps.cache-key.outputs.key }}
 
     # Verify cache was saved properly
     - name: Cache verify
       if: ${{ inputs.cache == 'true' && steps.cache-alr.outputs.cache-hit != 'true' }}
       uses: actions/cache/restore@v4
       with:
-        path: unused # Forced to provide it
+        path: |
+          ~/.cache/alire
+          ~/.config/alire
+          ~/.local/share/alire
+          ./alire_install
+          ~/AppData/Local/alire
         key: ${{steps.cache-key.outputs.key}}
         lookup-only: true
-        fail-on-cache-miss: true
+        fail-on-cache-miss: false