.travis.yml

language: rust
cache: cargo
rust:
  - stable
  - beta
  - nightly

# always test things that aren't pushes (like PRs)
# never test tags or pushes to non-master branches (wait for PR)
# https://github.com/travis-ci/travis-ci/issues/2200#issuecomment-441395545)
if: type != push OR (tag IS blank AND branch = master)

# an entry in stage=test will be generated for each rust/os combination.
# each entry will run these commands.
script:
  - cargo test
jobs:
  allow_failures:
    - rust: nightly
  include:
    - &check
      stage: check # do a pre-screen to make sure this is even worth testing
      script: cargo check --all-targets
      rust: stable
      os: linux
    - <<: *check # also test oldest known-good stable
      rust: 1.31.1
    - stage: test # then run the tests
      rust: stable
      os: osx
    - rust: stable
      os: windows
    - &linux
      stage: test
      rust: stable
      os: linux
    - <<: *linux
      rust: beta
    - <<: *linux
      rust: nightly
    - stage: lint # we lint on beta to future-proof
      name: "Rust: beta, rustfmt"
      rust: beta
      os: linux
      script:
        - rustup component add rustfmt-preview
        - cargo fmt -v -- --check
    - name: "Rust: nightly, rustfmt" # and on nightly with allow_fail
      rust: nightly
      os: linux
      script:
        - rustup component add rustfmt-preview
        - cargo fmt -v -- --check
    - name: "Rust: beta, clippy"
      rust: beta
      os: linux
      script:
        - rustup component add clippy-preview
        - touch ./src/lib.rs && cargo clippy -- -D warnings
    - name: "Rust: nightly, clippy"
      rust: nightly
      os: linux
      script:
        - rustup component add clippy-preview
        - touch ./src/lib.rs && cargo clippy -- -D warnings
    - <<: *linux
      stage: coverage
      rust: nightly
      env: CACHE_NAME=coverage
      sudo: required
      script:
        - RUSTFLAGS="--cfg procmacro2_semver_exempt" cargo install --force cargo-tarpaulin || true
        - cargo tarpaulin --out Xml
        - bash <(curl -s https://codecov.io/bash)
        - cargo clean -p bus # ensure we don't cache build for coverage
stages:
 - check
 - test
 - lint
 - coverage