Restore tag search

Source/model/scene/Group.swift

@@ -25,6 +25,35 @@ open class Group: Node {
         self.contentsVar.node = self
     }
 
+    // Searching
+
+    override public func nodeBy(tag: String) -> Node? {
+        if let node = super.nodeBy(tag: tag) {
+            return node
+        }
+
+        for child in contents {
+            if let node = child.nodeBy(tag: tag) {
+                return node
+            }
+        }
+
+        return .none
+    }
+
+    override public func nodesBy(tag: String) -> [Node] {
+        var result = [Node]()
+        contents.forEach { child in
+            result.append(contentsOf: child.nodesBy(tag: tag))
+        }
+
+        if let node = super.nodeBy(tag: tag) {
+            result.append(node)
+        }
+
+        return result
+    }
+
     override open var bounds: Rect? {
         return BoundsUtils.getNodesBounds(contents)
     }

Source/model/scene/Node.swift

@@ -38,6 +38,20 @@ open class Node: Drawable {
         set(val) { effectVar.value = val }
     }
 
+    // MARK: - Searching
+    public func nodeBy(tag: String) -> Node? {
+        if self.tag.contains(tag) {
+            return self
+        }
+
+        return .none
+    }
+
+    public func nodesBy(tag: String) -> [Node] {
+        return [nodeBy(tag: tag)].compactMap { $0 }
+    }
+
+    // MARK: - Events
     internal var animationObservers = [AnimationObserver]()
 
     var touchPressedHandlers = [ChangeHandler<TouchEvent>]()

Source/views/MacawView.swift

@@ -196,7 +196,7 @@ open class MacawView: MView, MGestureRecognizerDelegate {
         renderer.render(in: ctx, force: false, opacity: node.opacity)
     }
 
-    private func calculateZPosition(_ nodeRenderer: NodeRenderer?, currentIndex: Int = 0) -> Int {
+    @discardableResult private func calculateZPosition(_ nodeRenderer: NodeRenderer?, currentIndex: Int = 0) -> Int {
         nodeRenderer?.zPosition = currentIndex
         if let groupRenderer = nodeRenderer as? GroupRenderer {
             var i = currentIndex + 1