Optimize tree walk to avoid too depth function call stack.

packages/jaeger-ui/src/utils/TreeNode.js

@@ -83,7 +83,18 @@ export default class TreeNode {
   }
 
   walk(fn, depth = 0) {
-    TreeNode.iterFunction(fn, depth)(this);
-    this.children.forEach(child => child.walk(fn, depth + 1));
+    const nodeStack = [];
+    let actualDepth = depth;
+    nodeStack.push({ node: this, depth: actualDepth });
+    while (nodeStack.length) {
+      const { node, depth: nodeDepth } = nodeStack.pop();
+      fn(node.value, node, nodeDepth);
+      actualDepth = nodeDepth + 1;
+      let i = node.children.length - 1;
+      while (i >= 0) {
+        nodeStack.push({ node: node.children[i], depth: actualDepth });
+        i--;
+      }
+    }
   }
 }

packages/jaeger-ui/src/utils/TreeNode.test.js

@@ -264,3 +264,30 @@ it('walk() should iterate over every item once in the right order', () => {
 
   treeRoot.walk(value => expect(value).toBe(++i));
 });
+
+it('walk() should iterate over every item and compute the right deep on each node', () => {
+  /**
+   *     C0
+   *    /
+   *   B0 – C1
+   *  /
+   * A – B1 – C2
+   *      \
+   *      C3 – D
+   */
+
+  const nodeA = new TreeNode('A');
+  const nodeB0 = new TreeNode('B0');
+  const nodeB1 = new TreeNode('B1');
+  const nodeC3 = new TreeNode('C3');
+  const depthMap = { A: 0, B0: 1, B1: 1, C0: 2, C1: 2, C2: 2, C3: 2, D: 3 };
+  nodeA.addChild(nodeB0);
+  nodeA.addChild(nodeB0);
+  nodeA.addChild(nodeB1);
+  nodeB0.addChild('C0');
+  nodeB0.addChild('C1');
+  nodeB1.addChild('C2');
+  nodeB1.addChild(nodeC3);
+  nodeC3.addChild('D');
+  nodeA.walk((value, node, depth) => expect(depth).toBe(depthMap[value]));
+});