Get fixed issue references from GitHub pull request body

get-issue-refs.js

/*
 * Get fixed issue references from GitHub pull request body
 */
function getIssueRefs(pullRequestBody, defaultRepoName) {
  // ref: https://help.github.com/en/articles/closing-issues-using-keywords
  const keywords = 'close|closed|closes|fix|fixed|fixes|resolve|resolved|resolves';
  // ref: https://help.github.com/en/articles/autolinked-references-and-urls#issues-and-pull-requests
  const refTypes = [
    // #000
    '#',
    // org/repo#000
    '([a-z-]+/[a-z-.]+)#',
    // GH-000
    'GH-',
    // https://github.com/org/repo/issues/000
    'https:\\/\\/github\\.com\\/([a-z-]+\\/[a-z-.]+)\\/issues\\/',
  ].join('|');
  const regex = new RegExp(`(?:${keywords}) (?:${refTypes})(\\d+)`, 'gi');
  const result = [];
  let match;

  while (match = regex.exec(pullRequestBody)) {
    const [, repoName1, repoName2, number] = match;

    result.push({
      repoName: repoName1 || repoName2 || defaultRepoName,
      number: parseInt(number),
    });
  }

  return result;
}

get-issue-refs.test.js

getIssueRefs(
  // body of a pull request
  'Fixes #1, Resolves bar/repo-name#105\n\nLorem ipsum dolor sit amet',
  // repoName used for number-only references (e.g. Fixes #000)
  'foo/repo-name',
);
/* returns: [
 {number: 1, repoName: 'foo/repo-name'},
 {number: 105, repoName: 'bar/repo-name'},
] */