code: async function hasBreakingChange() {
    debug('checking for breaking changes between HEAD and upstream/master');
    const bodies = await exec('git log upstream/master.. --format=%b');
  
    if (/^BREAKING CHANGE:/.test(bodies)) {
      debug('found breaking change');
  
      return true;
    }
    debug('no breaking changes detected');
  
    return false;
  }
docs: Determines if there are any breaking changes between HEAD and upstream/master
  @returns {boolean}