code: function walk() {
        return revWalk.next().then(function(oid) {
          if (!oid) {
            return;
          }
  
          return repo.getCommit(oid).then(function(commit) {
            console.log("Commit:", commit.toString());
            return walk();
          });
        });
      }
docs: Now that we have the starting point pushed onto the walker, we start asking for ancestors. It will return them in the sorting order we asked for as commit oids. We can then lookup and parse the commited pointed at by the returned OID; note that this operation is specially fast since the raw contents of the commit object will be cached in memory