difftest.yml

# Differential testing against a real SQLite build.
#
# This is separate from CI because it downloads the pinned SQLite release
# and compiles it, which the ordinary test run must not depend on. It is the
# only thing that exercises error fidelity at scale: the vendored corpus is
# almost all valid SQL, so mutating it -- and mutating the ~36k inputs of
# SQLite's own fuzzdata databases, which are the opposite -- is how
# divergent messages and offsets get found.
name: difftest

on:
  schedule:
    - cron: "17 4 * * 1" # Mondays, early
  workflow_dispatch:
    inputs:
      seed:
        description: "PRNG seed (default: the run id, so each run is new ground)"
        default: ""
      per:
        description: "mutations per input"
        default: "60"

jobs:
  difftest:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: actions/setup-go@v5
        with:
          go-version-file: go.mod
      - name: Cache the pinned SQLite artifacts
        uses: actions/cache@v4
        with:
          path: .sqlite
          key: sqlite-${{ hashFiles('internal/sqlitesrc/sqlitesrc.go', 'internal/sqlitesrc/oracle/oracle.c') }}
      # The seed defaults to the run id rather than to a constant: a weekly
      # job with a fixed seed re-checks the same mutations forever. Roughly
      # 17M checks, a few minutes on a four-core runner -- the oracle runs
      # as a pool of batch-mode processes, so the cost is nearly all meyer.
      - run: >
          go run ./cmd/difftest
          -per ${{ github.event.inputs.per || '60' }}
          -depth 3
          -seed ${{ github.event.inputs.seed || github.run_id }}