1 files changed, 61 insertions, 0 deletions
diff --git a/devtools/shared/heapsnapshot/tests/xpcshell/test_HeapSnapshot_getObjectNodeId_01.js b/devtools/shared/heapsnapshot/tests/xpcshell/test_HeapSnapshot_getObjectNodeId_01.js
new file mode 100644
index 0000000000..26997dd904
--- /dev/null
+++ b/devtools/shared/heapsnapshot/tests/xpcshell/test_HeapSnapshot_getObjectNodeId_01.js
@@ -0,0 +1,61 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+"use strict";
+
+// Test ChromeUtils.getObjectNodeId()
+
+function run_test() {
+  // Create a test object, which we want to analyse
+  const testObject = {
+    foo: {
+      bar: {},
+    },
+  };
+
+  const path = ChromeUtils.saveHeapSnapshot({ runtime: true });
+  const snapshot = ChromeUtils.readHeapSnapshot(path);
+
+  // Get the NodeId for our test object
+  const objectNodeIdRoot = ChromeUtils.getObjectNodeId(testObject);
+  const objectNodeIdFoo = ChromeUtils.getObjectNodeId(testObject.foo);
+  const objectNodeIdBar = ChromeUtils.getObjectNodeId(testObject.foo.bar);
+
+  // Also try to ensure that this is the right object via its retained path
+  const shortestPaths = snapshot.computeShortestPaths(
+    objectNodeIdRoot,
+    [objectNodeIdBar],
+    50
+  );
+  ok(shortestPaths);
+  ok(shortestPaths instanceof Map);
+  Assert.equal(
+    shortestPaths.size,
+    1,
+    "We get only one path between the root object and bar object"
+  );
+
+  const paths = shortestPaths.get(objectNodeIdBar);
+  Assert.equal(paths.length, 1, "There is only one path between root and bar");
+  Assert.equal(
+    paths[0].length,
+    2,
+    "The shortest path is made of two edges: foo and bar"
+  );
+
+  const [path1, path2] = paths[0];
+  Assert.equal(
+    path1.predecessor,
+    objectNodeIdRoot,
+    "The first edge goes from the root object"
+  );
+  Assert.equal(path1.edge, "foo", "The first edge is the foo attribute");
+
+  Assert.equal(
+    path2.predecessor,
+    objectNodeIdFoo,
+    "The second edge goes from the foo object"
+  );
+  Assert.equal(path2.edge, "bar", "The first edge is the bar attribute");
+
+  do_test_finished();
+}