ci: test upcoming Cranelift release branch

.github/workflows/cranelift-release-branch.yml

@@ -0,0 +1,119 @@
+name: Test upcoming Cranelift release branch
+
+on:
+  schedule:
+    # Run daily so we don't miss the release branch cut.
+    - cron: "0 3 * * *"
+  workflow_dispatch: {}
+
+defaults:
+  run:
+    shell: bash
+
+permissions: {}
+
+env:
+  CARGO_BUILD_INCREMENTAL: false
+  RUSTFLAGS: "-Dwarnings"
+
+jobs:
+  test_upcoming_cranelift_release:
+    runs-on: ubuntu-latest
+    timeout-minutes: 90
+
+    steps:
+      - uses: actions/checkout@v6
+
+      - name: Determine latest Wasmtime release branch
+        id: wasmtime_release_branch
+        run: |
+          set -euo pipefail
+          branches="$(
+            git ls-remote --heads https://github.com/bytecodealliance/wasmtime.git "refs/heads/release-*" \
+              | awk '{print $2}' \
+              | sed 's#refs/heads/##' \
+              | sort -V
+          )"
+          if [[ -z "${branches}" ]]; then
+            echo "No wasmtime release branches found"
+            exit 1
+          fi
+          latest="$(echo "${branches}" | tail -n 1)"
+          echo "Latest release branch: ${latest}"
+          echo "branch=${latest}" >> "$GITHUB_OUTPUT"
+
+      - name: Skip if already tested
+        id: tested_cache
+        uses: actions/cache@v5
+        with:
+          path: .ci/cranelift-release-tested
+          key: cranelift-release-tested-${{ steps.wasmtime_release_branch.outputs.branch }}
+
+      - name: Mark tested (cache payload)
+        if: steps.tested_cache.outputs.cache-hit != 'true'
+        run: |
+          mkdir -p .ci/cranelift-release-tested
+          echo "${{ steps.wasmtime_release_branch.outputs.branch }}" > .ci/cranelift-release-tested/branch.txt
+
+      - name: Patch Cargo.toml to use release branch Cranelift
+        if: steps.tested_cache.outputs.cache-hit != 'true'
+        run: |
+          set -euo pipefail
+          branch="${{ steps.wasmtime_release_branch.outputs.branch }}"
+
+          python3 - <<'PY'
+          import pathlib, re, os
+          cargo_toml = pathlib.Path("Cargo.toml")
+          s = cargo_toml.read_text(encoding="utf-8")
+
+          branch = os.environ["WASMTIME_RELEASE_BRANCH"]
+          patch_lines = "\n".join([
+              f'cranelift-codegen = {{ git = "https://github.com/bytecodealliance/wasmtime.git", branch = "{branch}" }}',
+              f'cranelift-frontend = {{ git = "https://github.com/bytecodealliance/wasmtime.git", branch = "{branch}" }}',
+              f'cranelift-module = {{ git = "https://github.com/bytecodealliance/wasmtime.git", branch = "{branch}" }}',
+              f'cranelift-native = {{ git = "https://github.com/bytecodealliance/wasmtime.git", branch = "{branch}" }}',
+              f'cranelift-jit = {{ git = "https://github.com/bytecodealliance/wasmtime.git", branch = "{branch}" }}',
+              f'cranelift-object = {{ git = "https://github.com/bytecodealliance/wasmtime.git", branch = "{branch}" }}',
+          ])
+
+          # Ensure a [patch.crates-io] section exists.
+          if "[patch.crates-io]" not in s:
+              s += "\n\n[patch.crates-io]\n"
+
+          # Remove any previous CI-inserted patch block.
+          s = re.sub(
+              r"(?ms)^\n?# BEGIN CI WASMTIME RELEASE PATCH\n.*?^\# END CI WASMTIME RELEASE PATCH\n",
+              "\n",
+              s,
+          )
+
+          # Insert immediately after the [patch.crates-io] header.
+          s = re.sub(
+              r"(?m)^\[patch\.crates-io\]\s*$",
+              "[patch.crates-io]\n"
+              "# BEGIN CI WASMTIME RELEASE PATCH\n"
+              f"{patch_lines}\n"
+              "# END CI WASMTIME RELEASE PATCH",
+              s,
+              count=1,
+          )
+
+          cargo_toml.write_text(s, encoding="utf-8")
+          PY
+        env:
+          WASMTIME_RELEASE_BRANCH: ${{ steps.wasmtime_release_branch.outputs.branch }}
+
+      - name: Prepare dependencies
+        if: steps.tested_cache.outputs.cache-hit != 'true'
+        run: ./y.sh prepare
+
+      - name: Build (sysroot none)
+        if: steps.tested_cache.outputs.cache-hit != 'true'
+        run: ./y.sh build --sysroot none
+
+      - name: Test
+        if: steps.tested_cache.outputs.cache-hit != 'true'
+        env:
+          TARGET_TRIPLE: x86_64-unknown-linux-gnu
+        run: ./y.sh test
+