check-crlf-extended

GitHub Action to detect files with CRLF, LF, or mixed line endings

Maintain consistent line endings across your repository and prevent platform-induced issues caused by misconfigured Git settings (especially core.autocrlf on Windows).

Features

• ✅ Detect CRLF, LF, or mixed line endings
• 🎯 Flexible file filtering with glob or regex patterns
• 📁 Configurable directory depth scanning
• ⚡ Lightweight implementation using standard POSIX tools

---

Quick Start

name: Check Line Endings
on: [push, pull_request]

jobs:
  check-line-endings:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      
      - name: Check for CRLF files
        uses: kforeverisback/check-crlf-extended@v2
        with:
          line_ending_type: CRLF

Configuration

Inputs

Parameter	Description	Default
directory	Directory to scan (relative to $GITHUB_WORKSPACE)	.
line_ending_type	Line ending type to detect: CRLF, LF, or MIXED (case-insensitive)	crlf
include_pattern	Include files matching this pattern	*
exclude_pattern	Exclude files matching this pattern	``
pattern_type	Pattern matching type: shell_glob or regex	shell_glob
max_dir_depth	Maximum directory depth to search (root = depth 1)	999

Pattern Matching

• shell_glob: Matches against base filenames only (e.g., *.txt)
• regex: Matches against full file paths using egrep syntax

Note: When using regex, see the find manual for pattern syntax.

Usage Examples

Basic CRLF Detection

- name: Check for Windows line endings
  uses: kforeverisback/check-crlf-extended@v2
  with:
    line_ending_type: CRLF

Advanced Pattern Filtering

- name: Check specific file types with exclusions
  uses: kforeverisback/check-crlf-extended@v2
  with:
    directory: ./src
    line_ending_type: LF
    include_pattern: '*.{js,ts,py}'
    exclude_pattern: '*.min.*'
    pattern_type: shell_glob

Regex-based Filtering

- name: Check with regex exclusions
  uses: kforeverisback/check-crlf-extended@v2
  with:
    line_ending_type: MIXED
    exclude_pattern: '.*(test|spec).*\.(js|ts)$'
    pattern_type: regex

Non-blocking Check

- name: Check line endings (allow failures)
  uses: kforeverisback/check-crlf-extended@v2
  continue-on-error: true
  with:
    directory: ./docs
    line_ending_type: MIXED

How It Works

This action uses standard POSIX utilities (find, egrep, hexdump) to:

1. Scan the specified directory (excluding .git by default)
2. Apply include/exclude patterns to filter files
3. Analyze line endings in matching files
4. Report files that match the specified line ending type

Exit Behavior:

• Returns exit code 0 when no matching files are found
• Returns non-zero exit code when matching files are detected (fails the workflow step unless continue-on-error: true)

References

• Git attributes for line ending control
• GitHub's guide to Git line endings
• Understanding line endings

Credits

Built upon erclu/check-crlf with extended functionality and enhanced logging capabilities.