name: CI

on:
  push:
    # Run in PRs and for bors, but not on master.
    branches:
      - 'auto'
      - 'try'
  pull_request:
    branches:
      - 'master'
  schedule:
    # Use <https://crontab.guru> to conveniently edit cron schedule.
    - cron: '0 7 * * *' # At 07:00 UTC every day.

jobs:
  build:
    runs-on: ${{ matrix.os }}
    env:
      RUST_BACKTRACE: 1
      HOST_TARGET: ${{ matrix.host_target }}
    strategy:
      matrix:
        build: [linux64, macos, win32]
        include:
          - build: linux64
            os: ubuntu-latest
            host_target: x86_64-unknown-linux-gnu
          - build: macos
            os: macos-latest
            host_target: x86_64-apple-darwin
          - build: win32
            os: windows-latest
            host_target: i686-pc-windows-msvc
    steps:
      - uses: actions/checkout@v2

      # We install gnu-tar because BSD tar is buggy on macOS builders of GHA.
      # See <https://github.com/actions/cache/issues/403>.
      - name: Install GNU tar
        if: runner.os == 'macOS'
        run: |
          brew install gnu-tar
          echo "/usr/local/opt/gnu-tar/libexec/gnubin" >> $GITHUB_PATH

      # Cache the global cargo directory, but NOT the local `target` directory which
      # we cannot reuse anyway when the nightly changes (and it grows quite large
      # over time).
      - name: Add cache for cargo
        uses: actions/cache@v2
        with:
          path: |
            # Taken from <https://doc.rust-lang.org/nightly/cargo/guide/cargo-home.html#caching-the-cargo-home-in-ci>.
            ~/.cargo/bin
            ~/.cargo/registry/index
            ~/.cargo/registry/cache
            ~/.cargo/git/db
            # contains package information of crates installed via `cargo install`.
            ~/.cargo/.crates.toml
          key: ${{ runner.os }}-cargo-${{ hashFiles('**/Cargo.lock') }}
          restore-keys: ${{ runner.os }}-cargo

      - name: Install rustup-toolchain-install-master and xargo
        shell: bash
        run: |
          cargo install rustup-toolchain-install-master
          cargo install xargo

      - name: Install "master" toolchain
        shell: bash
        run: |
          if [[ ${{ github.event_name }} == 'schedule' ]]; then
            RUSTC_HASH=$(git ls-remote https://github.com/rust-lang/rust.git master | awk '{print $1}')
          else
            RUSTC_HASH=$(< rust-version)
          fi
          rustup-toolchain-install-master \
            -f \
            -n master "$RUSTC_HASH" \
            -c rust-src \
            -c rustc-dev \
            -c llvm-tools \
            --host ${{ matrix.host_target }}
          rustup default master

      - name: Show Rust version
        run: |
          rustup show
          rustc -Vv
          cargo -V

      - name: Test
        run: bash ./ci.sh

  # These jobs doesn't actually test anything, but they're only used to tell
  # bors the build completed, as there is no practical way to detect when a
  # workflow is successful listening to webhooks only.
  #
  # ALL THE PREVIOUS JOBS NEED TO BE ADDED TO THE `needs` SECTION OF THIS JOB!
  end-success:
    name: bors build finished
    runs-on: ubuntu-latest
    needs: [build]
    if: github.event.pusher.name == 'bors' && success()
    steps:
      - name: mark the job as a success
        run: exit 0
  end-failure:
    name: bors build finished
    runs-on: ubuntu-latest
    needs: [build]
    if: github.event.pusher.name == 'bors' && (failure() || cancelled())
    steps:
      - name: mark the job as a failure
        run: exit 1

  # Send a Zulip notification when a cron job fails
  cron-fail-notify:
    name: cronjob failure notification
    runs-on: ubuntu-latest
    needs: [build]
    if: github.event_name == 'schedule' && (failure() || cancelled())
    steps:
      - name: Install zulip-send
        run: pip3 install zulip
      - name: Send Zulip notification
        shell: bash
        env:
          ZULIP_BOT_EMAIL: ${{ secrets.ZULIP_BOT_EMAIL }}
          ZULIP_API_TOKEN: ${{ secrets.ZULIP_API_TOKEN }}
        run: |
          ~/.local/bin/zulip-send --stream miri --subject "Cron Job Failure" \
            --message 'Dear @**RalfJ** and @**oli**

          It would appear that the Miri cron job build failed. Would you mind investigating this issue?

          Thanks in advance!
          Sincerely,
          The Miri Cronjobs Bot' \
            --user $ZULIP_BOT_EMAIL --api-key $ZULIP_API_TOKEN --site https://rust-lang.zulipchat.com