Function createGithubFormatter

packages/bumpy/src/core/changelog-github.ts:49–151

(options: GithubChangelogOptions = {})

 *   "changelog": ["github", { "internalAuthors": ["theoephraim"] }]
 */
export function createGithubFormatter(options: GithubChangelogOptions = {}): ChangelogFormatter {
  const includeCommitLink = options.includeCommitLink ?? false;
  const thankContributors = options.thankContributors ?? true;
  const internalAuthorsSet = new Set(
    [...DEFAULT_INTERNAL_AUTHORS, ...(options.internalAuthors ?? [])].map((a) => a.toLowerCase()),
  );

  return async (ctx: ChangelogContext) => {
    const { release, bumpFiles, date } = ctx;
    const repoSlug = options.repo ?? detectRepo();
    const serverUrl = process.env.GITHUB_SERVER_URL || 'https://github.com';

    const lines: string[] = [];
    lines.push(`## ${release.newVersion}`);
    lines.push(`<sub>${date}</sub>`);
    lines.push('');

    const relevantBumpFiles = bumpFiles.filter((bf) => release.bumpFiles.includes(bf.id));
    const sorted = sortBumpFilesByType(relevantBumpFiles, release.name);

    for (const bf of sorted) {
      if (!bf.summary || isChangelogSuppressed(bf, release.name)) continue;

      const type = getBumpTypeForPackage(bf, release.name);
      const tag = ` *(${type})*`;

      // Extract metadata overrides from summary (pr, commit, author lines)
      const { cleanSummary, overrides } = extractSummaryMeta(bf.summary);

      // Look up git/PR info, with overrides taking precedence
      const gitInfo = resolveBumpFileInfo(bf.id, repoSlug, serverUrl, overrides);

      const summaryLines = trimBlankEdges(cleanSummary.split('\n'));
      const linkify = (s: string) => linkifyIssueRefs(s, serverUrl, repoSlug);

      // Build the prefix: PR link, commit link, thanks
      const { links, thanks } = formatPrefix(
        gitInfo,
        serverUrl,
        repoSlug,
        includeCommitLink,
        thankContributors,
        internalAuthorsSet,
      );

      // Assemble metadata: links, tag, thanks
      const parts = [links, tag, thanks].filter(Boolean);
      const hasMeta = parts.length > 0;
      const meta = parts.join(' ');

      if (summaryLines.length === 0) {
        // Metadata only (e.g. summary was just `pr:`/`author:` lines)
        if (hasMeta) lines.push(`- ${meta}`);
      } else if (hasMeta && summaryNeedsBlockLayout(cleanSummary)) {
        // Long/multiline/markdown summary reads poorly inline — put it on its own
        // line(s) below the metadata.
        lines.push(`- ${meta}`);
        for (const sl of summaryLines) {