How to use @lerna/describe-ref - 1 common examples

const { forcePublish, conventionalCommits, conventionalGraduate, excludeDependents } = commandOptions;

  // If --conventional-commits and --conventional-graduate are both set, ignore --force-publish
  const useConventionalGraduate = conventionalCommits && conventionalGraduate;
  const forced = getPackagesForOption(useConventionalGraduate ? conventionalGraduate : forcePublish);

  const packages =
    filteredPackages.length === packageGraph.size
      ? packageGraph
      : new Map(filteredPackages.map(({ name }) => [name, packageGraph.get(name)]));

  let committish = commandOptions.since;

  if (hasTags(execOpts)) {
    // describe the last annotated tag in the current branch
    const { sha, refCount, lastTagName } = describeRef.sync(execOpts, commandOptions.includeMergedTags);
    // TODO: warn about dirty tree?

    if (refCount === "0" && forced.size === 0 && !committish) {
      // no commits since previous release
      log.notice("", "Current HEAD is already released, skipping change detection.");

      return [];
    }

    if (commandOptions.canary) {
      // if it's a merge commit, it will return all the commits that were part of the merge
      // ex: If `ab7533e` had 2 commits, ab7533e^..ab7533e would contain 2 commits + the merge commit
      committish = `${sha}^..${sha}`;
    } else if (!committish) {
      // if no tags found, this will be undefined and we'll use the initial commit
      committish = lastTagName;