Harden CI against transient Bazelisk setup failures

[Copilot]

build_and_test failed before any Bazel build/test work due to a timeout in bazel-contrib/setup-bazel (api.github.com connect timeout). This change makes Bazelisk setup resilient to transient network failure in the macOS CI path.

• Workflow resilience update (.github/workflows/ci_macos.yml)

  • Added a two-attempt Bazelisk setup sequence in build_and_test.
  • First setup attempt is allowed to fail; second attempt runs only when the first did not succeed.
  • Second attempt is strict (fails job if unsuccessful).

• Fail-fast verification

  • Added an explicit post-setup check to ensure bazelisk is actually available before fetch/build/test steps.
  • Emits a clear failure message when setup still does not produce a usable Bazelisk binary.

- name: Setup Bazelisk (attempt 1)
  id: setup_bazelisk_1
  continue-on-error: true
  uses: bazel-contrib/setup-bazel@0.19.0
  with:
    bazelisk-version: "1.29.0"

- name: Setup Bazelisk (attempt 2)
  if: steps.setup_bazelisk_1.outcome != 'success'
  continue-on-error: false
  uses: bazel-contrib/setup-bazel@0.19.0
  with:
    bazelisk-version: "1.29.0"

- name: Verify Bazelisk installation
  run: bazelisk version || (echo "Failed to install Bazelisk after two setup attempts, or Bazelisk is not available on PATH." && exit 1)

[tameware]

Hope it will help!

[Copilot]

Pull request overview

This PR improves GitHub Actions CI resilience by retrying Bazelisk setup and adding an explicit “tool is installed” verification step before running Bazel fetch/build/test work.

Changes:

• Add a two-attempt bazel-contrib/setup-bazel (Bazelisk) installation sequence with a conditional second attempt.
• Add a post-setup verification step intended to fail fast when Bazelisk is not usable.
• Apply the same pattern across macOS and Linux CI workflows/jobs.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
.github/workflows/ci_macos.yml	Adds two-attempt Bazelisk setup plus a verification step in macOS build_and_test and sanitizers jobs.
.github/workflows/ci_linux.yml	Adds two-attempt Bazelisk setup plus a verification step across Linux build_and_test, asan, and tsan jobs.

Comments suppressed due to low confidence (2)

.github/workflows/ci_linux.yml:118

• The workflow verifies bazelisk, but subsequent steps in this job use the bazel command (bazel fetch/test). To fail fast on a missing toolchain, verify bazel is available (or verify both bazel and bazelisk).

      - name: Verify Bazelisk installation
        run: bazelisk version || (echo "Failed to install Bazelisk after two setup attempts, or Bazelisk is not available on PATH." && exit 1)

.github/workflows/ci_linux.yml:179

• The workflow verifies bazelisk, but subsequent steps in this job use the bazel command (bazel fetch/test). To fail fast on a missing toolchain, verify bazel is available (or verify both bazel and bazelisk).

      - name: Verify Bazelisk installation
        run: bazelisk version || (echo "Failed to install Bazelisk after two setup attempts, or Bazelisk is not available on PATH." && exit 1)

[zzcgumn]

This looks like an improvement which I am happy to merge. Is there a way to move the duplicated code to a separate script that is invoked from two places?

[tameware]

Is there a way to move the duplicated code to a separate script that is invoked from two places?

Possible and desirable. Done. This also highlighted that the change was missing from Windows and WASM builds. It's now everywhere. All four CI workflows call it with:

- name: Setup Bazelisk
  uses: ./.github/actions/setup-bazelisk

That’s 7 call sites (Linux ×3, macOS ×2, Windows, WASM).

[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.

Comments suppressed due to low confidence (1)

.github/workflows/ci_linux.yml:32

• The PR description still frames the resilience change as macOS-specific, but this PR updates all CI workflows (Linux/Windows/WASM/macOS) to use the new ./.github/actions/setup-bazelisk composite action. Please update the PR description to reflect the broader scope (or, if unintended, revert the non-macOS workflow changes).

      # 3️⃣ Install Bazelisk (recommended Bazel launcher)
      - name: Setup Bazelisk
        uses: ./.github/actions/setup-bazelisk