diff --git a/HTMLKit/HTMLNode.m b/HTMLKit/HTMLNode.m
index be7a196..f2751e9 100644
--- a/HTMLKit/HTMLNode.m
+++ b/HTMLKit/HTMLNode.m
@@ -319,18 +319,18 @@ NS_INLINE void CheckInvalidCombination(HTMLNode *parent, HTMLNode *node, NSStrin
 
 	void (^ hierarchyError)() = ^{
 		[NSException raise:HTMLKitHierarchyRequestError
-					format:@"%@: Hierarchy Request Error. The operation would yield an incorrect node tree.",
-		 NSStringFromSelector(_cmd)];
+					format:@"%@: Hierarchy Request Error, inserting (%@) into (%@). The operation would yield an incorrect node tree.",
+		 NSStringFromSelector(_cmd), self, node];
 	};
 
 	if (self.type == HTMLNodeDocument) {
 		switch (node.type) {
 			case HTMLNodeDocumentFragment:
-				if (self.childNodesCount > 1 ||
-					[self hasChildNodeOfType:HTMLNodeText]) {
+				if (node.childNodesCount > 1 ||
+					[node hasChildNodeOfType:HTMLNodeText]) {
 					hierarchyError();
-				} else if (self.childNodesCount == 1) {
-					if (self.hasChildNodes ||
+				} else if (node.childNodesCount == 1) {
+					if ([self hasChildNodeOfType:HTMLNodeElement] ||
 						child.type == HTMLNodeDocumentType ||
 						child.nextSibling.type == HTMLNodeDocumentType) {
 						hierarchyError();
diff --git a/HTMLKitTests/HTMLKitNodesTests.m b/HTMLKitTests/HTMLKitNodesTests.m
index a38959d..9c2dccc 100644
--- a/HTMLKitTests/HTMLKitNodesTests.m
+++ b/HTMLKitTests/HTMLKitNodesTests.m
@@ -537,4 +537,41 @@
 	XCTAssertNoThrow([[HTMLTemplate new] appendNode:text]);
 }
 
+- (void)testValidDocumentFragmentInsertionIntoDocument
+{
+	HTMLDocument *document = [HTMLDocument new];
+	HTMLDocumentFragment *fragment = [[HTMLDocumentFragment alloc] initWithDocument:document];
+
+	void (^ reset)() = ^ {
+		[fragment removeAllChildNodes];
+		[document removeAllChildNodes];
+	};
+
+	[fragment appendNode:[HTMLText new]];
+	XCTAssertThrows([document appendNode:fragment]);
+
+	reset();
+	[fragment appendNode:[HTMLElement new]];
+	[fragment appendNode:[HTMLElement new]];
+	XCTAssertThrows([document appendNode:fragment]);
+
+	reset();
+	[fragment appendNode:[HTMLElement new]];
+	[document appendNode:[HTMLElement new]];
+	XCTAssertThrows([document appendNode:fragment]);
+
+	reset();
+	HTMLDocumentType *doctype = [HTMLDocumentType new];
+	[fragment appendNode:[HTMLElement new]];
+	[document appendNode:doctype];
+	XCTAssertThrows([document insertNode:fragment beforeChildNode:doctype]);
+
+	reset();
+	HTMLComment *doctypePreviousSibling = [HTMLComment new];
+	[fragment appendNode:[HTMLElement new]];
+	[document appendNode:doctypePreviousSibling];
+	[document appendNode:doctype];
+	XCTAssertThrows([document insertNode:fragment beforeChildNode:doctypePreviousSibling]);
+}
+
 @end