clang-format-ci

Run clang-format from your CI to automatically suggest style changes in PRs as in-line comments.

Prerequisites

This script requires clang-format and git clang-format.

Usage

This script is intended to be invoked from a continuous integration service that supports running arbitrary scripts.

Travis CI

You will likely want to set up your GitHub API token as an encrypted environment variable. You can then use the following .travis.yml, being sure to fill in the TODOs:

language: objective-c
sudo: false
env:
  global:
  - LC_CTYPE=en_US.UTF-8
  - LANG=en_US.UTF-8
  matrix:
    secure: # TODO: Configure $GITHUB_TOKEN as a secure environment variable
matrix:
  include:
  - osx_image: xcode10
before_install:
  - brew install clang-format
  - mkdir bin
  - curl -Ls "https://raw.githubusercontent.com/llvm-mirror/clang/c510fac5695e904b43d5bf0feee31cc9550f110e/tools/clang-format/git-clang-format" -o "bin/git-clang-format"
  - chmod +x bin/git-clang-format
  - export PATH="$(pwd)/bin:$PATH"
  - git clone --branch <TODO: version> https://github.com/material-foundation/clang-format-ci.git
script:
  - if [ -n "$TRAVIS_PULL_REQUEST_SLUG" ]; then ./clang-format-ci/check-pull-request.sh --api_token "$GITHUB_TOKEN" --repo "$TRAVIS_PULL_REQUEST_SLUG" --pr "$TRAVIS_PULL_REQUEST" --commit "$TRAVIS_PULL_REQUEST_SHA" --target_branch "$TRAVIS_BRANCH"; fi

Kokoro

You will need to provide both an API token and repo name to the script. Both of these values should be defined as environment variables in your Kokoro configuration.

Example installation script using a pre-built clang-format binary:

CLANG_FORMAT_VERSION="r343360"
CLANG_FORMAT_SHA="9d2a3aeaee65f09ae5405dd33812d167fadd48aba712965cdb3238e5d8837255"
GIT_CLANG_FORMAT_VERSION="c510fac5695e904b43d5bf0feee31cc9550f110e"
GIT_CLANG_FORMAT_SHA="1f6cfad79f90ea202dcf2d52a360186341a589cdbfdee05b0e7694f912aa9820"

install_clang_format() {
  mkdir bin
  pushd bin >> /dev/null

  echo "Downloading clang-format..."
  curl -Ls "https://github.com/material-foundation/clang-format/releases/download/$CLANG_FORMAT_VERSION/clang-format" -o "clang-format"
  if openssl sha -sha256 "clang-format" | grep -q "$CLANG_FORMAT_SHA"; then
    echo "SHAs match. Proceeding."
  else
    echo "clang-format does not match sha. Aborting."
    exit 1
  fi
  chmod +x "clang-format"

  echo "Downloading git-clang-format..."
  curl -Ls "https://raw.githubusercontent.com/llvm-mirror/clang/$GIT_CLANG_FORMAT_VERSION/tools/clang-format/git-clang-format" -o "git-clang-format"
  if openssl sha -sha256 "git-clang-format" | grep -q "$GIT_CLANG_FORMAT_SHA"; then
    echo "SHAs match. Proceeding."
  else
    echo "git-clang-format does not match sha. Aborting."
    exit 1
  fi
  chmod +x "git-clang-format"

  export PATH="$(pwd):$PATH"

  popd >> /dev/null
}

if ! git clang-format -h > /dev/null 2> /dev/null; then
  install_clang_format
fi

git clone --branch <TODO: version> https://github.com/material-foundation/clang-format-ci.git
./clang-format-ci/check-pull-request.sh \
  --api_token "$API_TOKEN" \
  --repo "$REPO" \
  --pr "$KOKORO_GITHUB_PULL_REQUEST_NUMBER" \
  --commit "$KOKORO_GITHUB_PULL_REQUEST_COMMIT" \
  --target_branch "$KOKORO_GITHUB_PULL_REQUEST_TARGET_BRANCH"