chore(ci): Key the test data cache on the data repo HEAD

Author: effigies

.github/workflows/test.yml

@@ -23,6 +23,7 @@ env:
   ITK_GLOBAL_DEFAULT_NUMBER_OF_THREADS: 4
   ANTSPATH: /usr/share/miniconda/bin/
   NIFREEZE_WERRORS: 1
+  TEST_DATA_REPO: https://gin.g-node.org/nipreps-data/tests-nifreeze
 
 concurrency:
   group: ${{ github.workflow }}-${{ github.ref }}
@@ -32,30 +33,37 @@ permissions:
   contents: read
 
 jobs:
-  cache-data:
+  cache-test-data:
     runs-on: 'ubuntu-latest'
+    outputs:
+      SHA: ${{ steps.test-head.outputs.SHA }}
     steps:
+      - name: Check remote HEAD
+        id: test-head
+        run: git ls-remote $TEST_DATA_REPO | awk '/HEAD/{ print "SHA=" $1 }' >> $GITHUB_OUTPUT
+      - uses: actions/cache@v4
+        id: test-data
+        with:
+          path: /home/runner/nifreeze-tests/
+          key: data-v1-${{ steps.test-head.outputs.SHA }}
+          restore-keys: |
+            data-v1
+            data-v0
       - name: Install the latest version of uv
         uses: astral-sh/setup-uv@v5
+        if: steps.test-data.outputs.cache-hit != 'true'
       - name: Install datalad
+        if: steps.test-data.outputs.cache-hit != 'true'
         run: |
           uvx datalad-installer --sudo ok git-annex
           uv tool install --with=datalad-osf --with=datalad-next datalad
           uv tool install --with=datalad-next datalad-osf
           datalad wtf
-      - uses: actions/cache@v4
-        id: test-data
-        with:
-          path: /home/runner/nifreeze-tests/
-          key: data-v1
-          restore-keys: |
-            data-v1
-            data-v0
       - name: Get test data with DataLad
         if: steps.test-data.outputs.cache-hit != 'true'
         run: |
           if [[ ! -d "${TEST_DATA_HOME}" ]]; then
-            datalad install -rg --source=https://gin.g-node.org/nipreps-data/tests-nifreeze.git ${TEST_DATA_HOME}
+            datalad install -rg --source=${TEST_DATA_REPO} ${TEST_DATA_HOME}
           else
             cd ${TEST_DATA_HOME}
             datalad update --merge -r .
@@ -65,7 +73,7 @@ jobs:
   stable:
     # Unit tests only on Linux/Python 3.12
     runs-on: 'ubuntu-latest'
-    needs: ['cache-data']
+    needs: ['cache-test-data']
     steps:
       - uses: actions/checkout@v4
         with:
@@ -78,21 +86,10 @@ jobs:
       - name: Install ANTs
         run: |
           conda install -c conda-forge ants=2.5
-      - name: Install datalad
-        run: |
-          python -m pip install datalad-installer
-          datalad-installer --sudo ok git-annex
-          python -m pip install datalad datalad-osf
-          datalad wtf
       - uses: actions/cache/restore@v4
         with:
           path: /home/runner/nifreeze-tests/
-          key: data-v1
-      - name: Update test data
-        run: |
-          cd ${TEST_DATA_HOME}
-          datalad update --merge -r .
-          datalad get -r -J4 *
+          key: data-v1-${{ needs.cache-test-data.outputs.SHA }}
       - name: Install TeX Live
         run: |
           sudo apt-get update