Merge pull request #9 from TomCaserta/issue-8

#8 Check if parent node is a document or document fragment

src/querySelectorDeep.js

@@ -77,7 +77,7 @@ function findMatchingElement(splitSelector, possibleElementsIndex, root) {
         let position = possibleElementsIndex;
         let parent = element;
         let foundElement = false;
-        while (parent) {
+        while (parent && !isDocumentNode(parent)) {
             const foundMatch = parent.matches(splitSelector[position]);
             if (foundMatch && position === 0) {
                 foundElement = true;
@@ -111,6 +111,14 @@ function splitByCharacterUnlessQuoted(selector, character) {
     }, { a: [''] }).a;
 }
 
+/**
+ * Checks if the node is a document node or not.
+ * @param {Node} node
+ * @returns {node is Document | DocumentFragment}
+ */
+function isDocumentNode(node) {
+    return node.nodeType === Node.DOCUMENT_FRAGMENT_NODE || node.nodeType === Node.DOCUMENT_NODE;
+}
 
 function findParentOrHost(element, root) {
     const parentNode = element.parentNode;

test/basic.spec.js

@@ -95,6 +95,13 @@ describe("Basic Suite", function() {
             expect(testSubComponent.textContent).toEqual('Child 2')
         });
 
+        it('returns null when reaching the document node and no matching parent was found', function() {
+            const rootComponent = createTestComponent(parent, {
+                childClassName: 'child',
+            })
+            const testSubComponent = querySelectorDeep('.parent .child', rootComponent);
+            expect(testSubComponent).toBeNull();
+        });
     });