1 files changed, 55 insertions, 0 deletions
diff --git a/devtools/client/memory/test/unit/test_action-set-display.js b/devtools/client/memory/test/unit/test_action-set-display.js
new file mode 100644
index 000000000..43ea975da
--- /dev/null
+++ b/devtools/client/memory/test/unit/test_action-set-display.js
@@ -0,0 +1,55 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+"use strict";
+
+/**
+ * Tests the action creator `setCensusDisplay()` for display changing. Does not
+ * test refreshing the census information, check `setCensusDisplayAndRefresh`
+ * action for that.
+ */
+
+let { censusDisplays, snapshotState: states, censusState, viewState } = require("devtools/client/memory/constants");
+let { setCensusDisplay } = require("devtools/client/memory/actions/census-display");
+let { takeSnapshotAndCensus } = require("devtools/client/memory/actions/snapshot");
+const { changeView } = require("devtools/client/memory/actions/view");
+
+function run_test() {
+  run_next_test();
+}
+
+// We test setting an invalid display, which triggers an assertion failure.
+EXPECTED_DTU_ASSERT_FAILURE_COUNT = 1;
+
+add_task(function* () {
+  let front = new StubbedMemoryFront();
+  let heapWorker = new HeapAnalysesClient();
+  yield front.attach();
+  let store = Store();
+  let { getState, dispatch } = store;
+
+  dispatch(changeView(viewState.CENSUS));
+
+  // Test default display with no snapshots
+  equal(getState().censusDisplay.breakdown.by, "coarseType",
+        "default coarseType display selected at start.");
+
+  dispatch(setCensusDisplay(censusDisplays.allocationStack));
+  equal(getState().censusDisplay.breakdown.by, "allocationStack",
+        "display changed with no snapshots");
+
+  // Test invalid displays
+  try {
+    dispatch(setCensusDisplay({}));
+    ok(false, "Throws when passing in an invalid display object");
+  } catch (e) {
+    ok(true, "Throws when passing in an invalid display object");
+  }
+  equal(getState().censusDisplay.breakdown.by, "allocationStack",
+    "current display unchanged when passing invalid display");
+
+  // Test new snapshots
+  dispatch(takeSnapshotAndCensus(front, heapWorker));
+  yield waitUntilCensusState(store, s => s.census, [censusState.SAVED]);
+  equal(getState().snapshots[0].census.display, censusDisplays.allocationStack,
+        "New snapshots use the current, non-default display");
+});