Run scheduled tests on latest release as well as the main

.github/workflows/scheduled_tests.yml

@@ -6,11 +6,34 @@ on:
   workflow_dispatch:
 
 jobs:
-  test:
-    name: Tests (latest)
+  get-latest-release:
+    name: Get latest release tag
     runs-on: ubuntu-latest
+    outputs:
+      latest-tag: ${{ steps.get-tag.outputs.tag }}
+    steps:
+      - name: Get latest release tag
+        id: get-tag
+        run: |
+          TAG=$(gh release list --repo ${{ github.repository }} --limit 1 --json tagName -q '.[0].tagName')
+          echo "tag=$TAG" >> "$GITHUB_OUTPUT"
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+  test-stable:
+    name: Tests (${{ matrix.ref }}, Scarb stable)
+    needs: get-latest-release
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        ref:
+          - main
+          - ${{ needs.get-latest-release.outputs.latest-tag }}
     steps:
       - uses: actions/checkout@v6
+        with:
+          ref: ${{ matrix.ref }}
       - uses: dtolnay/rust-toolchain@stable
       - uses: Swatinem/rust-cache@c19371144df3bb44fab255c43d04cbc2ab54d1c4 # v2.9.1
       - uses: hrishikesh-kadam/setup-lcov@6c1aa0cc9e1c02f9f58f01ac599f1064ccc83470 # v1.1.0
@@ -19,3 +42,91 @@ jobs:
           scarb-version: latest
       - uses: foundry-rs/setup-snfoundry@16e23ddd0e2845f38727c92f4b913a7b728cda9e # v6.0.0
       - run: cargo test --release --features allows-excluding-macros
+
+  test-nightly:
+    name: Tests (${{ matrix.ref }}, Scarb nightly)
+    needs: get-latest-release
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        ref:
+          - main
+          - ${{ needs.get-latest-release.outputs.latest-tag }}
+    steps:
+      - uses: actions/checkout@v6
+        with:
+          ref: ${{ matrix.ref }}
+      - uses: dtolnay/rust-toolchain@stable
+      - uses: Swatinem/rust-cache@c19371144df3bb44fab255c43d04cbc2ab54d1c4 # v2.9.1
+      - uses: hrishikesh-kadam/setup-lcov@6c1aa0cc9e1c02f9f58f01ac599f1064ccc83470 # v1.1.0
+      - uses: software-mansion/setup-scarb@2a96b748888e3329ee44ac9ac073d930e692b3cd # v1.5.1
+        with:
+          scarb-version: nightly
+      - uses: foundry-rs/setup-snfoundry@16e23ddd0e2845f38727c92f4b913a7b728cda9e # v6.0.0
+      - run: cargo test --release --features allows-excluding-macros
+
+  # Stable failures always notify — no deduplication.
+  notify_stable_failed:
+    name: Notify on stable failure
+    runs-on: ubuntu-latest
+    if: always() && needs.test-stable.result == 'failure'
+    needs: [test-stable]
+    steps:
+      - name: Notifying about stable check fail!
+        uses: slackapi/slack-github-action@v3.0.3
+        with:
+          webhook: ${{ secrets.SLACK_SCHEDULED_CHECK_FAILURE_WEBHOOK_URL }}
+          webhook-type: webhook-trigger
+          payload: |
+            {
+              "url": "${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}"
+            }
+
+  # Nightly failures notify only once per Scarb stable version. The cache key is
+  # the current Scarb stable release tag, so a new stable release resets alerting
+  # automatically (the key changes -> cache miss -> notification allowed again).
+  notify_nightly_failed:
+    name: Notify on nightly failure (deduped per Scarb stable)
+    runs-on: ubuntu-latest
+    if: always() && needs.test-nightly.result == 'failure'
+    needs: [test-nightly]
+    steps:
+      - name: Get current Scarb stable version
+        id: stable
+        run: |
+          VER=$(gh release list --repo software-mansion/scarb \
+                  --exclude-pre-releases --limit 1 \
+                  --json tagName -q '.[0].tagName')
+          echo "version=$VER" >> "$GITHUB_OUTPUT"
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Check if already notified for this Scarb stable
+        id: dedup
+        uses: actions/cache/restore@v4
+        with:
+          path: .notified
+          key: notified-scarb-nightly-${{ steps.stable.outputs.version }}
+
+      - name: Notifying about nightly check fail!
+        if: steps.dedup.outputs.cache-hit != 'true'
+        uses: slackapi/slack-github-action@v3.0.3
+        with:
+          webhook: ${{ secrets.SLACK_SCHEDULED_CHECK_FAILURE_WEBHOOK_URL }}
+          webhook-type: webhook-trigger
+          payload: |
+            {
+              "url": "${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}"
+            }
+
+      - name: Record that we notified for this stable
+        if: steps.dedup.outputs.cache-hit != 'true'
+        run: mkdir -p .notified && echo "${{ github.run_id }}" > .notified/run
+
+      - name: Save notification marker
+        if: steps.dedup.outputs.cache-hit != 'true'
+        uses: actions/cache/save@v4
+        with:
+          path: .notified
+          key: notified-scarb-nightly-${{ steps.stable.outputs.version }}