version: 2.1

executors:
  default:
    description: Executor environment for building Rust crates.
    docker:
      - image: circleci/rust:1

commands:
  update_toolchain:
    description: Update the Rust toolchain to use for building.
    parameters:
      toolchain:
        description: Rust toolchain to use. Overrides the default toolchain (stable) or any toolchain specified in the project via `rust-toolchain`.
        type: string
        default: ""
    steps:
      - run:
          name: Update toolchain
          command: |
            test -z "<<parameters.toolchain>>" || echo "<<parameters.toolchain>>" >rust-toolchain
            rustup show active-toolchain
      - run:
          name: Version information
          command: |
            rustup --version
            rustc --version
            cargo --version

  build:
    description: Build all targets of a Rust crate.
    steps:
      - run:
          name: Calculate dependencies
          command: |
            rustc --version >rust-version
            test -e Cargo.lock || cargo generate-lockfile
      - restore_cache:
          keys:
            - v6-cargo-cache-{{arch}}-{{checksum "rust-version"}}-{{checksum "Cargo.lock"}}
      - run:
          name: Build all targets
          command: cargo build --tests --all-features
      - save_cache:
          paths:
            - /usr/local/cargo/registry
            - target
          key: v6-cargo-cache-{{arch}}-{{checksum "rust-version"}}-{{checksum "Cargo.lock"}}

  check:
    description: Check all targets of a Rust crate.
    steps:
      - run:
          name: Calculate dependencies
          command: test -e Cargo.lock || cargo generate-lockfile
      - run:
          name: Check all targets
          command: |
            if rustup component add clippy; then
              cargo clippy --all --all-targets --all-features -- -Dwarnings
            else
              echo Skipping clippy
            fi

  test:
    description: Run all tests of a Rust crate. Make sure to build first.
    parameters:
      release:
        description: By default, the crate is build in debug mode without optimizations. Set this to true to compile in release mode.
        type: boolean
        default: false
    steps:
      - run:
          name: Run all tests
          command: cargo test --all-features

jobs:
  check:
    description: Check a Rust crate.
    parameters:
      toolchain:
        description: Rust toolchain to use. Overrides the default toolchain (stable) or any toolchain specified in the project via `rust-toolchain`.
        type: string
        default: ""
    executor: default
    steps:
      - checkout
      - update_toolchain:
          toolchain: <<parameters.toolchain>>
      - check

  test:
    description: Builds a Rust crate and runs all tests.
    parameters:
      toolchain:
        description: Rust toolchain to use. Overrides the default toolchain (stable) or any toolchain specified in the project via `rust-toolchain`.
        type: string
        default: ""
    executor: default
    steps:
      - checkout
      - update_toolchain:
          toolchain: <<parameters.toolchain>>
      - build
      - test

workflows:
  Project:
    jobs:
      - test:
          name: cargo test (stable)
          toolchain: stable
      - test:
          name: cargo test (beta)
          toolchain: beta
      - test:
          name: cargo test (nightly)
          toolchain: nightly