diff --git a/src/Document.js b/src/Document.js
index 603a0e1..c0f675b 100644
--- a/src/Document.js
+++ b/src/Document.js
@@ -1,3 +1,5 @@
+/* eslint-disable no-dupe-class-members */
+
 const libxmljs = require('libxmljs');
 const utils = require('./utils');
 
@@ -66,7 +68,11 @@
     return this.get(`count(${xpath})`);
   }
 
-  encoding(enc = null) {
+  encoding() {
+    return this._original.encoding();
+  }
+
+  encoding(enc) {
     return this._original.encoding(enc);
   }
 
@@ -140,7 +146,13 @@
     return this._original.rngValidate(rng);
   }
 
-  root(node = null) {
+  root() {
+    this.assertNoContentError();
+
+    return this._original.root();
+  }
+
+  root(node) {
     this.assertNoContentError();
 
     return this._original.root(node);