ollection.addSnapshot(
        scopedId, 'cat', 'cc::PictureLayerImpl', 15, {}, 'cc::LayerImpl');
    collection.updateBounds();
    assert.strictEqual(10, collection.bounds.min);
    assert.strictEqual(15, collection.bounds.max);
    assert.strictEqual(s15.objectInstance, i10);
    assert.strictEqual(i10.name, 'cc::PictureLayerImpl');
    assert.strictEqual(i10.baseTypeName, 'cc::LayerImpl');
  });

  test('deleteThenSnapshotWithCustomBase', function() {
    const collection = new tr.model.ObjectCollection