code: function BlameRangeList(blame) {
    var ranges = blame.ranges;
  
    return ranges
      .filter(function(range) {
        return (
          range &&
          range.commit &&
          range.commit.author &&
          range.commit.author.user &&
          range.commit.author.user.login
        );
      })
      .map(function(range) {
        return BlameRange({
          age: range.age,
          count: range.endingLine - range.startingLine + 1,
          login: range.commit.author.user.login
        });
      })
      .filter(Boolean);
  }
docs: Convert raw blame data into BlameRanges
  @param {Object} blame - GitHub blame data
  @returns {Array} list of BlameRanges