action.yml

name: 'Changed Files with filter'
description: 'A GitHub Action that outputs a list of changed files in pull requests and commits.'
author: 'YUMEMI Inc.'
branding:
  icon: 'file'
  color: 'blue'
inputs:
  separator:
    description: 'Separator between file names in plain format.'
    required: false
    default: ' '
  format:
    description: 'Output format for list of file names. Either plain or json.'
    required: false
    default: 'plain'
  patterns:
    description: 'Path pattern to filter. See README for details.'
    required: false
  statuses:
    description: 'Status of pull request files to include from output. Specify added, modified, renamed, and removed separately.'
    required: false
  exclude-statuses:
    description: 'Status of pull request files to exclude from output. Specify added, modified, renamed, and removed separately.'
    required: false
  run:
    description: 'Bash script to run if at least one file exists after filtering.'
    required: false
  head-ref:
    description: 'Current branch, tag, or commit SHA to compare with base.'
    required: false
    default: ${{ github.event_name == 'pull_request_target' && format('refs/pull/{0}/merge',github.event.number) || github.sha }}
  base-ref:
    description: 'Branch, tag, or commit SHA as a basis for comparison.'
    required: false
    default: |-
      ${{
        (github.event_name == 'pull_request' && github.base_ref) ||
        (github.event_name == 'pull_request_target' && github.base_ref) ||
        (github.event_name == 'push' && (startsWith(github.event.before, '0000') && github.event.repository.default_branch || github.event.before)) ||
        (github.event_name == 'merge_group' && github.event.merge_group.base_sha) ||
        github.event.repository.default_branch
      }}
outputs:
  files:
    description: 'List of file names after filtering.'
    value: ${{ steps.result.outputs.exists != null && (inputs.format == 'json' && steps.result.outputs.files || join(fromJSON(steps.result.outputs.files), inputs.separator)) || '' }}
  exists:
    description: 'Whether at least one file exists after filtering.'
    value: ${{ steps.result.outputs.exists }}
  additions:
    description: 'Total additions after filtering.'
    value: ${{ steps.result.outputs.additions }}
  deletions:
    description: 'Total deletions after filtering.'
    value: ${{ steps.result.outputs.deletions }}
  changes:
    description: 'Total changes after filtering.'
    value: ${{ steps.result.outputs.changes }}
  action-path:
    description: 'Used to access artifact files.'
    value: ${{ steps.prepare.outputs.action-path }}
runs:
  using: 'composite'
  steps:
    - name: Prepare
      id: prepare
      shell: bash
      env:
        PATTERNS: ${{ inputs.patterns }}
        STATUSES: ${{ inputs.statuses }}
        EXC_STATUSES: ${{ inputs.exclude-statuses }}
        IS_VALID_FORMAT: ${{ inputs.format != null && contains(fromJSON('["plain","json"]'), inputs.format) }}
        HEAD_REF: ${{ inputs.head-ref }}
        BASE_REF: ${{ inputs.base-ref }}
        GH_REPO: ${{ github.repository }} # for GitHub CLI
        GH_TOKEN: ${{ github.token }} # for GitHub CLI
      run: |
        echo "::debug::gh version: $(gh --version | tr '\n' ' ')"
        echo "::debug::jq version: $(jq --version)"
        echo "action-path=$GITHUB_ACTION_PATH" >> "$GITHUB_OUTPUT"
        source "$GITHUB_ACTION_PATH/raise_error.sh"

        patterns="$("$GITHUB_ACTION_PATH/get_multiline_input.sh" "$PATTERNS")"

        statuses=$("$GITHUB_ACTION_PATH/get_statuses.sh" "$STATUSES") > /dev/null 2>&1 || raise_error "'statuses' input can be used added, modified, renamed and removed."
        exc_statuses=$("$GITHUB_ACTION_PATH/get_statuses.sh" "$EXC_STATUSES") > /dev/null 2>&1 || raise_error "'exclude-statuses' input can be used added, modified, renamed and removed."

        if [ "$IS_VALID_FORMAT" != 'true' ]; then raise_error "'format' input must be plain or json."; fi

        if [[ -z "$HEAD_REF" || -z "$BASE_REF" ]]; then raise_error "Specify 'head-ref' and 'base-ref' inputs."; fi

        # have pemisson?
        gh api repos/{owner}/{repo}/branches --silent > /dev/null 2>&1 || raise_error "May not have 'contents: read' permission."

        head_sha="$(gh api "repos/{owner}/{repo}/commits/$HEAD_REF" | jq -r '.sha')" > /dev/null 2>&1 || raise_error "'head-ref' input is not valid."
        base_sha="$(gh api "repos/{owner}/{repo}/commits/$BASE_REF" | jq -r '.sha')" > /dev/null 2>&1 || raise_error "'base-ref' input is not valid."

        head_previous_sha="$(gh api "repos/{owner}/{repo}/commits/$head_sha" | jq -r '.parents[0].sha')"
        if [ "$head_previous_sha" == 'null' ]; then raise_error "No history. 'head-ref' input reference may be the first commit."; fi

        if [ "$base_sha" == "$head_sha" ]; then
          files='[]'
        elif [ "$base_sha" == "$head_previous_sha" ]; then
          # avoid using copare, which has a limit of 300 files
          files="$(gh api "repos/{owner}/{repo}/commits/$head_sha" --paginate | jq '.files[]|{ filename, status, additions, deletions, changes }' | jq -cs)"
          if [ "$(echo "$files" | jq 'length')" -ge 3000 ]; then raise_error "Cannot handle more than 3000 files."; fi
        else
          # files do not support pagination and are limited to 300 files
          files="$(gh api "repos/{owner}/{repo}/compare/${base_sha}...${head_sha}" | jq -c '[.files[]|{ filename, status, additions, deletions, changes }]')"
          if [ "$(echo "$files" | jq 'length')" -ge 300 ]; then raise_error "Cannot handle more than 300 files when 'base-ref' input is specified."; fi
        fi

        {
          echo "patterns=$patterns"; echo "statuses=$statuses"; echo "exc-statuses=$exc_statuses"
        } >> "$GITHUB_OUTPUT"
        echo -n "$files" > "$GITHUB_ACTION_PATH/files.json" # output large data to filles
    - name: Filter files
      id: filter
      uses: actions/github-script@v7
      env:
        PATTERNS: ${{ steps.prepare.outputs.patterns }}
        STATUSES: ${{ steps.prepare.outputs.statuses }}
        EXC_STATUSES: ${{ steps.prepare.outputs.exc-statuses }}
      with:
        script: |
          const { GITHUB_ACTION_PATH, PATTERNS, STATUSES, EXC_STATUSES } = process.env;
          const fs = require('fs').promises, minimatch = require(`${GITHUB_ACTION_PATH}/dist/index.js`);
          const files = JSON.parse(await fs.readFile(`${GITHUB_ACTION_PATH}/files.json`, 'utf-8'));
          const patterns = JSON.parse(PATTERNS), statuses = JSON.parse(STATUSES), excStatuses = JSON.parse(EXC_STATUSES);
          const incPatterns = patterns.filter(p => !p.startsWith('!'));
          const excPatterns = patterns.filter(p => p.startsWith('!')).map(p => p.slice(1));
          const option = { dot: true, nocomment: true, nonegate: true, noext: true };
          const filteredFiles = files.filter(f => incPatterns.length === 0 || incPatterns.some(p => minimatch(f.filename, p, option)))
            .filter(f => !excPatterns.some(p => minimatch(f.filename, p, option)))
            .filter(f => statuses.length === 0 || statuses.some(s => f.status === s))
            .filter(f => !excStatuses.some(s => f.status === s));
          await fs.writeFile(`${GITHUB_ACTION_PATH}/filtered_files.json`, JSON.stringify(filteredFiles), 'utf-8');
    - name: Output results
      id: result
      shell: bash
      run: |
        files="$(cat "$GITHUB_ACTION_PATH/filtered_files.json")"
        {
          if [ "$files" != '[]' ]; then
            echo "files=$(echo "$files" | jq -c '[.[].filename]')"
            echo 'exists=true'
            echo "additions=$(echo "$files" | jq '[.[].additions]|add')"
            echo "deletions=$(echo "$files" | jq '[.[].deletions]|add')"
            echo "changes=$(echo "$files" | jq '[.[].changes]|add')"
          else
            echo 'files=[]'; echo 'exists=false'; echo 'additions=0'; echo 'deletions=0'; echo 'changes=0'
          fi
        } >> "$GITHUB_OUTPUT"
    - name: Run script
      if: steps.result.outputs.exists == 'true' && inputs.run != null
      shell: bash
      run: |
        ${{ inputs.run }}