nightly-fuzz-test.yml

name: Non-deterministic fuzz tests
on:
  workflow_dispatch:
  schedule:
    # Run nightly at 0300
    - cron: "0 3 * * *"

permissions:
  contents: read

concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: true

env:
  # How long should we run the fuzzing for, in seconds.
  NOIR_AST_FUZZER_BUDGET_SECS: 1800

jobs:
  ast-fuzz:
    runs-on: ubuntu-latest
    permissions:
      contents: read
    steps:
      - name: Checkout
        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1

      - name: Setup toolchain
        uses: dtolnay/rust-toolchain@1.89.0
        with:
          targets: x86_64-unknown-linux-gnu

      - uses: taiki-e/install-action@just

      - name: Run fuzzer
        id: fuzz
        shell: bash
        run: |
          set -o pipefail
          just fuzz-nightly 2>&1 | tee fuzz-output.log
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
          RUST_MIN_STACK: 8388608

      - name: Extract fuzzer seeds
        if: failure()
        id: seeds
        shell: bash
        run: |
          ./.github/scripts/extract-fuzz-seeds.sh fuzz-output.log .
          seed_count=$(wc -l < seeds.txt | tr -d ' ')
          seeds=$(paste -sd, - < seeds.txt)
          echo "seed_count=${seed_count}" >> "$GITHUB_OUTPUT"
          echo "seeds=${seeds}" >> "$GITHUB_OUTPUT"

      - name: Upload fuzz failure artifact
        if: failure()
        uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7
        with:
          name: nightly-fuzz-failure
          path: |
            fuzz-output.log
            seeds.txt
            seeds-by-test.tsv
          retention-days: 30

      - name: Get current date
        id: date
        run: echo "DAY=date::$(date +'%u')" >> $GITHUB_OUTPUT

      - name: Notify Slack and dispatch ClaudeBox on failure
        id: claudebox
        if: ${{ failure() && steps.date.outputs.DAY <= 5 }}
        uses: ./.github/actions/claudebox-dispatch
        with:
          claudebox-url: ${{ secrets.CLAUDEBOX_URL }}
          claudebox-api-secret: ${{ secrets.CLAUDEBOX_API_SECRET }}
          repo: noir-lang/noir
          run-url: ${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}
          user: noir-nightly-fuzz
          mode: public
          target-ref: origin/${{ github.ref_name }}
          link: ${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}
          slack-bot-token: ${{ secrets.CLAUDEBOX_SLACK_BOT_TOKEN }}
          slack-channel: ${{ secrets.FUZZER_FAILURE_SLACK_CHANNEL_ID }}
          slack-alert: >-
            :rotating_light: <${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}|Nightly compiler fuzzing>
            failed — ${{ steps.seeds.outputs.seed_count }} seed(s): `${{ steps.seeds.outputs.seeds }}`.
            ClaudeBox is reproducing and diagnosing the failure in this thread.
          prompt: |
            The nightly Noir compiler fuzzer failed on `${{ github.ref_name }}`.

            Run: ${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}
            Failing seeds (${{ steps.seeds.outputs.seed_count }}): ${{ steps.seeds.outputs.seeds }}

            Working one by one, reproduce the fuzzer failures using those seeds
            against noir-lang/noir master. For each seed perform an RCA and determine
            whether they are from different underlying bugs or if they are all
            symptoms of the same issue. Create gists which detail the issue, with a
            suggested fix along with minimal loadbearing unit tests.

            Repository tooling may help; the `bisect-ssa-pass` skill is particularly
            useful for SSA failures. Check for known issues which trigger the fuzzer by
            looking for issues/PRs with the `AST Fuzzer` label, and say in this thread
            whether this is a duplicate.

            Post the RCA and the proposed fix in this thread and wait for a human to
            say go before opening a PR.

      - name: Send the existing fallback alert in Slack
        if: ${{ always() && steps.claudebox.outcome == 'failure' }}
        uses: slackapi/slack-github-action@dcb1066f776dd043e64d0e8ba94ca15cc7e1875d # v4.0.0
        with:
          webhook: ${{ secrets.FUZZING_ALERT_URL }}
          webhook-type: webhook-trigger
          payload: |
            workflow-url: ${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}
            seed-count: ${{ steps.seeds.outputs.seed_count }}
            seeds: "${{ steps.seeds.outputs.seeds }}"
            artifact-name: nightly-fuzz-failure