name: tests in CI

# Every integration test of the reference crate is run by a job, and none can run
# empty.
#
# The conformance workflows name the tests they run, one `--test NAME` at a time. A test
# file nobody adds to a step never runs, and a feature-gated one compiled in a step that
# lacks its feature reports `ok` with no test in it. Both have happened here, silently.
# scripts/check-tests-in-ci.py requires that every test file is named by a step or
# listed, with its reason, in the crate's tests/NOT-IN-CI.txt, and that every
# feature-gated one declares its features in Cargo.toml, so that cargo refuses to build
# it without them.
#
# No `paths:` filter, on purpose. On this forge a filter matches the files of the push,
# not of the pull request, so a later push that touches no test would leave the head with
# no run of this check. The job takes seconds: it reads files and builds nothing.

# One run per branch at a time. A push supersedes the run before it.
concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: true

on:
  push:
    branches: [main]
  pull_request:

# Runs on `linux-arm64`, not `linux`: these jobs read files and run scripts, so the CPU
# architecture does not matter to them, and the one `linux` (x86_64) runner is the
# fleet's bottleneck, with every Rust workspace's tests queued on it.
jobs:
  covered:
    name: every test file is run by a job or listed with its reason
    runs-on: linux-arm64
    timeout-minutes: 10
    steps:
      - uses: actions/checkout@v4

      # The check must be able to fail, or it is decoration.
      - name: The check fails closed (self-test)
        run: ./scripts/check-tests-in-ci-selftest.sh

      - name: Every test file is run or listed, and none can run empty
        run: python3 -I scripts/check-tests-in-ci.py