name: tests

# Runs the suite the README tells a reader to run, on the interpreter floors
# the package claims to support and on three operating systems. The test class
# TestEveryCommandInTheReadmeActuallyRuns executes the README's own commands,
# so a documentation change that stops working fails here rather than in
# somebody's terminal.

on:
  push:
    branches: [main]
  pull_request:
  workflow_dispatch:

permissions:
  contents: read

jobs:
  test:
    name: py${{ matrix.python-version }} on ${{ matrix.os }}
    runs-on: ${{ matrix.os }}
    env:
      # Windows runners hand a piped Python process the ANSI code page, and the
      # CLI prints non-ASCII. Set once here so every step agrees, including the
      # subprocesses the tests spawn.
      PYTHONIOENCODING: utf-8
    strategy:
      fail-fast: false
      matrix:
        os: [ubuntu-latest, windows-latest, macos-latest]
        python-version: ["3.9", "3.11", "3.13"]
    steps:
      - uses: actions/checkout@v4

      - uses: actions/setup-python@v5
        with:
          python-version: ${{ matrix.python-version }}

      # No install step on purpose: the package declares zero dependencies and
      # the tests are stdlib unittest. If either stops being true, this job is
      # the thing that notices.
      - name: Show the interpreter and confirm the no-deps claim
        run: python -c "import sys; print(sys.version)"

      - name: Run the suite
        run: python -m unittest discover -s tests -v

      - name: The README's own commands must run
        # Duplicated deliberately, and separately visible: this is the class
        # that fails when the documentation drifts away from the code, which
        # is the failure mode this project exists to talk about.
        run: python -m unittest tests.test_greencheck.TestEveryCommandInTheReadmeActuallyRuns -v

      - name: Build the wheel and the sdist, and check them
        run: |
          python -m pip install --quiet build twine
          python -m build
          python -m twine check dist/*

      - name: Install the built wheel into an empty environment and run it
        # The defect this catches: skills/ lived outside the package once, so
        # `greencheck skills` worked in a checkout and failed for everybody who
        # actually installed it. Kept in a script rather than inline shell
        # because the shell version used /tmp and $RUNNER_TEMP and produced exit
        # 127 on Windows, which is the same class of mistake as the one above.
        run: python tools/smoke_install.py dist