1 files changed, 112 insertions, 0 deletions
diff --git a/dom/heapsnapshot/tests/unit/test_DominatorTreeNode_insert_01.js b/dom/heapsnapshot/tests/unit/test_DominatorTreeNode_insert_01.js
new file mode 100644
index 000000000..979232ff4
--- /dev/null
+++ b/dom/heapsnapshot/tests/unit/test_DominatorTreeNode_insert_01.js
@@ -0,0 +1,112 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+// Test that we can insert new children into an existing DominatorTreeNode tree.
+
+const tree = makeTestDominatorTreeNode({ nodeId: 1000 }, [
+  makeTestDominatorTreeNode({}),
+  makeTestDominatorTreeNode({ nodeId: 2000 }, [
+    makeTestDominatorTreeNode({}),
+    makeTestDominatorTreeNode({ nodeId: 3000 }),
+    makeTestDominatorTreeNode({}),
+  ]),
+  makeTestDominatorTreeNode({}),
+]);
+
+const path = [1000, 2000, 3000];
+
+const newChildren = [
+  makeTestDominatorTreeNode({ parentId: 3000 }),
+  makeTestDominatorTreeNode({ parentId: 3000 }),
+];
+
+const moreChildrenAvailable = false;
+
+const expected = {
+  nodeId: 1000,
+  parentId: undefined,
+  label: undefined,
+  shallowSize: 1,
+  retainedSize: 7,
+  children: [
+    {
+      nodeId: 0,
+      label: undefined,
+      shallowSize: 1,
+      retainedSize: 1,
+      parentId: 1000,
+      moreChildrenAvailable: true,
+      children: undefined,
+    },
+    {
+      nodeId: 2000,
+      label: undefined,
+      shallowSize: 1,
+      retainedSize: 4,
+      parentId: 1000,
+      children: [
+        {
+          nodeId: 1,
+          label: undefined,
+          shallowSize: 1,
+          retainedSize: 1,
+          parentId: 2000,
+          moreChildrenAvailable: true,
+          children: undefined,
+        },
+        {
+          nodeId: 3000,
+          label: undefined,
+          shallowSize: 1,
+          retainedSize: 1,
+          parentId: 2000,
+          children: [
+            {
+              nodeId: 7,
+              parentId: 3000,
+              label: undefined,
+              shallowSize: 1,
+              retainedSize: 1,
+              moreChildrenAvailable: true,
+              children: undefined,
+            },
+            {
+              nodeId: 8,
+              parentId: 3000,
+              label: undefined,
+              shallowSize: 1,
+              retainedSize: 1,
+              moreChildrenAvailable: true,
+              children: undefined,
+            },
+          ],
+          moreChildrenAvailable: false
+        },
+        {
+          nodeId: 3,
+          label: undefined,
+          shallowSize: 1,
+          retainedSize: 1,
+          parentId: 2000,
+          moreChildrenAvailable: true,
+          children: undefined,
+        },
+      ],
+      moreChildrenAvailable: true
+    },
+    {
+      nodeId: 5,
+      label: undefined,
+      shallowSize: 1,
+      retainedSize: 1,
+      parentId: 1000,
+      moreChildrenAvailable: true,
+      children: undefined,
+    }
+  ],
+  moreChildrenAvailable: true
+};
+
+function run_test() {
+  assertDominatorTreeNodeInsertion(tree, path, newChildren, moreChildrenAvailable, expected);
+}