Defer generation of child nodes until necessary

2 files changed, 10 insertions, 4 deletions

diff --git a/src/main/java/org/zwobble/mammoth/internal/styles/HtmlPath.java b/src/main/java/org/zwobble/mammoth/internal/styles/HtmlPath.java
index 93025d9..979f292 100644
--- a/src/main/java/org/zwobble/mammoth/internal/styles/HtmlPath.java
+++ b/src/main/java/org/zwobble/mammoth/internal/styles/HtmlPath.java
@@ -4,6 +4,7 @@ import org.zwobble.mammoth.internal.html.HtmlNode;
 
 import java.util.List;
 import java.util.Map;
+import java.util.function.Supplier;
 
 import static org.zwobble.mammoth.internal.util.Lists.list;
 import static org.zwobble.mammoth.internal.util.Lists.reversed;
@@ -42,10 +43,10 @@ public class HtmlPath {
         this.elements = elements;
     }
 
-    public List<HtmlNode> wrap(List<HtmlNode> nodes) {
+    public Supplier<List<HtmlNode>> wrap(Supplier<List<HtmlNode>> generateNodes) {
         for (HtmlPathElement element : reversed(elements)) {
-            nodes = element.wrap(nodes);
+            generateNodes = element.wrap(generateNodes);
         }
-        return nodes;
+        return generateNodes;
     }
 }
diff --git a/src/main/java/org/zwobble/mammoth/internal/styles/HtmlPathElement.java b/src/main/java/org/zwobble/mammoth/internal/styles/HtmlPathElement.java
index 08221eb..4c4ff98 100644
--- a/src/main/java/org/zwobble/mammoth/internal/styles/HtmlPathElement.java
+++ b/src/main/java/org/zwobble/mammoth/internal/styles/HtmlPathElement.java
@@ -5,6 +5,7 @@ import org.zwobble.mammoth.internal.html.HtmlNode;
 
 import java.util.List;
 import java.util.Map;
+import java.util.function.Supplier;
 
 import static org.zwobble.mammoth.internal.util.Lists.list;
 import static org.zwobble.mammoth.internal.util.Maps.map;
@@ -32,7 +33,11 @@ public class HtmlPathElement {
         this.isCollapsible = isCollapsible;
     }
 
-    public List<HtmlNode> wrap(List<HtmlNode> nodes) {
+    public Supplier<List<HtmlNode>> wrap(Supplier<List<HtmlNode>> generateNodes) {
+        return () -> wrapNodes(generateNodes.get());
+    }
+
+    private List<HtmlNode> wrapNodes(List<HtmlNode> nodes) {
         return list(new HtmlElement(tagNames, attributes, nodes, isCollapsible));
     }
 }