version: 2.1

commands:
  setup-lints:
    steps:
      - run:
          name: Install cargo-audit
          command: cargo install cargo-audit
      - run:
          name: Install clippy
          command: rustup component add clippy

  # https://medium.com/@edouard.oger/rust-caching-on-circleci-using-sccache-c996344f0115
  setup-sccache:
    steps:
      - run:
          name: Install sccache
          command: |
            cargo install sccache
            # This configures Rust to use sccache.
            echo 'export "RUSTC_WRAPPER"="sccache"' >> $BASH_ENV
            # This is the maximum space sccache cache will use on disk.
            echo 'export "SCCACHE_CACHE_SIZE"="1G"' >> $BASH_ENV
            sccache --version

  restore-sccache-cache:
    steps:
      - restore_cache:
          name: Restore sccache cache
          key: sccache-cache-stable-{{ arch }}-{{ .Environment.CIRCLE_JOB }}
  save-sccache-cache:
    steps:
      - save_cache:
          name: Save sccache cache
          # We use {{ epoch }} to always upload a fresh cache:
          # Of course, restore_cache will not find this exact key,
          # but it will fall back to the closest key (aka the most recent).
          # See https://discuss.circleci.com/t/add-mechanism-to-update-existing-cache-key/9014/13
          key: sccache-cache-stable-{{ arch }}-{{ .Environment.CIRCLE_JOB }}-{{ epoch }}
          paths:
            - "~/.cache/sccache"

jobs:
  build:
    docker:
      - image: circleci/rust:latest
    steps:
      - checkout
      - setup-lints
      - setup-sccache
      - restore-sccache-cache
      - run: cargo test --all
      - run:
          name: Check style
          command: |
              cargo fmt --all -- --check
              cargo clippy --all-targets --all-features -- -D warnings
      - run:
          name: Audit Dependencies
          command: cargo audit
      - save-sccache-cache