code: function pushContext(state, tagName) {
          var noIndent = doNotIndent.hasOwnProperty(tagName) || (state.context && state.context.doIndent);
          var newContext = {
              tagName: tagName,
              prev: state.context,
              indent: state.context ? state.context.indent + indentUnit : 0,
              lineNumber: state.lineNumber,
              indented: state.indented,
              noIndent: noIndent
          };
          state.context = newContext;
      }
docs: go down a level in the document (hint: look at who calls this function to know what the contexts are)