name: Clang-Format Check

# This workflow verifies that all tracked C/C++ files in the repository

# are formatted according to the .clang-format rules.

#

# It uses:

# - clang-format (installed via apt)

# - a Go-based helper (cmd/clang-filter) via `go run`

# - the shell script `./scripts/_format_c_code.sh` to orchestrate everything

#

# The workflow runs:

# - on every push to any branch

# - on every pull request

on:

push:

branches:

- "**"

pull_request:

jobs:

clang-format-check:

runs-on: ubuntu-latest

steps:

#########################################################################

# 1) Check out the repository so we have access to:

# - source files

# - .clang-format

# - .clang-format-ignore

# - cmd/clang-filter

# - scripts/_format_c_code.sh

#########################################################################

- name: Check out repository

uses: actions/checkout@v6

with:

# Full git history is not strictly required for formatting,

# but some tools or future changes might rely on it.

fetch-depth: 0

#########################################################################

# 2) Install clang-format on the runner.

#

# We rely on Ubuntu's clang-format package. If you require a specific

# version, you can pin it here or use a prebuilt toolchain image.

#########################################################################

- name: Install clang-format

run: |

sudo apt-get update

sudo apt-get install -y clang-format

- name: Show clang-format version

run: clang-format --version

#########################################################################

# 3) Set up Go toolchain for `go run ./cmd/clang-filter`

#

# The Go helper uses github.com/sabhiram/go-gitignore to implement

# gitignore-style rules for .clang-format-ignore.

#########################################################################

- name: Set up Go

uses: actions/setup-go@v6

with:

go-version-file: go.mod

cache: false

# Optional but recommended: download all Go module dependencies up front.

# This avoids doing network fetches during `go run` and can speed up CI.

- name: Download Go modules

run: go mod download

#########################################################################

# 4) Run clang-format in CHECK mode via the shell script.

#

# The script:

# - collects tracked C/C++ files (git ls-files)

# - filters them via `go run ./cmd/clang-filter` using .clang-format-ignore

# - runs clang-format in CHECK mode (no in-place changes)

# - prints per-file errors using GitHub Actions "::error" annotations

# - fails the job (exit 1) if any file is misformatted

#########################################################################

- name: Run clang-format in check mode

run: |

chmod +x ./scripts/_format_c_code.sh

./scripts/_format_c_code.sh check