1 files changed, 46 insertions, 0 deletions
diff --git a/devtools/client/memory/test/unit/test_action_diffing_02.js b/devtools/client/memory/test/unit/test_action_diffing_02.js
new file mode 100644
index 000000000..fc68cee65
--- /dev/null
+++ b/devtools/client/memory/test/unit/test_action_diffing_02.js
@@ -0,0 +1,46 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+// Test that toggling diffing unselects all snapshots.
+
+const { snapshotState, censusState, viewState } = require("devtools/client/memory/constants");
+const { toggleDiffing } = require("devtools/client/memory/actions/diffing");
+const { takeSnapshotAndCensus } = require("devtools/client/memory/actions/snapshot");
+const { changeView } = require("devtools/client/memory/actions/view");
+
+function run_test() {
+  run_next_test();
+}
+
+add_task(function* () {
+  let front = new StubbedMemoryFront();
+  let heapWorker = new HeapAnalysesClient();
+  yield front.attach();
+  let store = Store();
+  const { getState, dispatch } = store;
+
+  dispatch(changeView(viewState.CENSUS));
+
+  equal(getState().diffing, null, "not diffing by default");
+
+  dispatch(takeSnapshotAndCensus(front, heapWorker));
+  dispatch(takeSnapshotAndCensus(front, heapWorker));
+  dispatch(takeSnapshotAndCensus(front, heapWorker));
+  yield waitUntilCensusState(store, s => s.census, [censusState.SAVED,
+                                                    censusState.SAVED,
+                                                    censusState.SAVED]);
+
+  ok(getState().snapshots.some(s => s.selected),
+     "One of the new snapshots is selected");
+
+  dispatch(toggleDiffing());
+  ok(getState().diffing, "now diffing after toggling");
+
+  for (let s of getState().snapshots) {
+    ok(!s.selected,
+       "No snapshot should be selected after entering diffing mode");
+  }
+
+  heapWorker.destroy();
+  yield front.detach();
+});