Node.root()

jhy · jhy · commit f78df946f00c · 2016-10-29T17:25:56.000-07:00
diff --git a/CHANGES b/CHANGES
@@ -9,6 +9,8 @@ jsoup changelog
  * Added new methods to Elements: next(query), nextAll(query), prev(query), prevAll(query) to select next and previous
    element siblings from a current selection, with optional selectors.
 
+ * Added Node.root() to get the topmost ancestor of a Node.
+
  * Bugfix: a "SYSTEM" flag in doctype tags would be incorrectly removed.
    <https://github.com/jhy/jsoup/issues/408>
 
diff --git a/src/main/java/org/jsoup/nodes/Element.java b/src/main/java/org/jsoup/nodes/Element.java
@@ -303,7 +303,7 @@ public boolean is(String cssQuery) {
      * @return if this element matches
      */
     public boolean is(Evaluator evaluator) {
-        return evaluator.matches(this.ownerDocument(), this);
+        return evaluator.matches((Element)this.root(), this);
     }
     
     /**
diff --git a/src/main/java/org/jsoup/nodes/Node.java b/src/main/java/org/jsoup/nodes/Node.java
@@ -245,21 +245,25 @@ public Node parent() {
     public final Node parentNode() {
         return parentNode;
     }
+
+    /**
+     * Get this node's root node; that is, its topmost ancestor. If this node is the top ancestor, returns {@code this}.
+     * @return topmost ancestor.
+     */
+    public Node root() {
+        Node node = this;
+        while (node.parentNode != null)
+            node = node.parentNode;
+        return node;
+    }
     
     /**
      * Gets the Document associated with this Node. 
      * @return the Document associated with this Node, or null if there is no such Document.
      */
     public Document ownerDocument() {
-        Node node = this;
-        while (true) {
-            if (node instanceof Document)
-                return (Document) node;
-            else if (node.parentNode == null)
-                return null;
-            else
-                node = node.parentNode;
-        }
+        Node root = root();
+        return (root instanceof Document) ? (Document) root : null;
     }
     
     /**
@@ -557,7 +561,8 @@ protected void outerHtml(Appendable accum) {
 
     // if this node has no document (or parent), retrieve the default output settings
     Document.OutputSettings getOutputSettings() {
-        return ownerDocument() != null ? ownerDocument().outputSettings() : (new Document("")).outputSettings();
+        Document owner = ownerDocument();
+        return owner != null ? owner.outputSettings() : (new Document("")).outputSettings();
     }
 
     /**
diff --git a/src/test/java/org/jsoup/nodes/NodeTest.java b/src/test/java/org/jsoup/nodes/NodeTest.java
@@ -157,6 +157,21 @@ public void handlesAbsOnProtocolessAbsoluteUris() {
         assertNull(doc.parent());
     }
 
+    @Test public void root() {
+        Document doc = Jsoup.parse("<div><p>Hello");
+        Element p = doc.select("p").first();
+        Node root = p.root();
+        assertTrue(doc == root);
+        assertNull(root.parent());
+        assertTrue(doc.root() == doc);
+        assertTrue(doc.root() == doc.ownerDocument());
+
+        Element standAlone = new Element(Tag.valueOf("p"), "");
+        assertTrue(standAlone.parent() == null);
+        assertTrue(standAlone.root() == standAlone);
+        assertTrue(standAlone.ownerDocument() == null);
+    }
+
     @Test public void before() {
         Document doc = Jsoup.parse("<p>One <b>two</b> three</p>");
         Element newNode = new Element(Tag.valueOf("em"), "");

Original file line number	Diff line number	Diff line change
`@@ -303,7 +303,7 @@ public boolean is(String cssQuery) {`
`303`	`303`	`* @return if this element matches`
`304`	`304`	`*/`
`305`	`305`	`public boolean is(Evaluator evaluator) {`
`306`		`- return evaluator.matches(this.ownerDocument(), this);`
	`306`	`+ return evaluator.matches((Element)this.root(), this);`
`307`	`307`	`}`
`308`	`308`
`309`	`309`	`/**`