Add Unit Tests to SnackbarCollection

chrome/android/junit/src/org/chromium/chrome/browser/snackbar/SnackbarCollectionUnitTest.java

Index: chrome/android/junit/src/org/chromium/chrome/browser/snackbar/SnackbarCollectionUnitTest.java
diff --git a/chrome/android/junit/src/org/chromium/chrome/browser/snackbar/SnackbarCollectionUnitTest.java b/chrome/android/junit/src/org/chromium/chrome/browser/snackbar/SnackbarCollectionUnitTest.java
new file mode 100644
index 0000000000000000000000000000000000000000..2a9ae1133cc4e58b6ba5d1ac4afb740d561a6cac
--- /dev/null
+++ b/chrome/android/junit/src/org/chromium/chrome/browser/snackbar/SnackbarCollectionUnitTest.java
@@ -0,0 +1,186 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.chrome.browser.snackbar;
+
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+
+import org.chromium.base.test.util.Feature;
+import org.chromium.chrome.browser.snackbar.SnackbarManager.SnackbarController;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.BlockJUnit4ClassRunner;
+
+/**
+ * Tests for {@link SnackbarCollection}.
+ */
+@RunWith(BlockJUnit4ClassRunner.class)
+public class SnackbarCollectionUnitTest implements SnackbarController {
+    private static final String ACTION_TITLE = "stack";
+    private static final String NOTIFICATION_TITLE = "queue";
+
+    private boolean mActionCalled;
+    private boolean mDismissCalled;
+
+    @Test
+    @Feature({"Browser", "Snackbar"})
+    public void testAddOverride() throws Exception {

[newt (away), 2016/01/28 17:32:00]

maybe: "testActionCoversNotification"

[Ian Wen, 2016/01/29 02:38:43]

Done.

+        SnackbarCollection collection = new SnackbarCollection();
+        assertTrue(collection.isEmpty());
+
+        Snackbar notiBar = makeNotificationSnackbar();
+        collection.add(notiBar);
+        assertFalse(collection.isEmpty());
+        assertEquals(notiBar, collection.getCurrent());
+
+        Snackbar actionBar = makeActionSnackbar();
+        collection.add(actionBar);
+        assertTrue(onDismissWasCalled());
+        assertFalse(collection.isEmpty());
+        assertEquals("Notibar was not overriden by actionBar!", actionBar, collection.getCurrent());

[newt (away), 2016/01/28 17:32:00]

use terms that other developers who see this test failure can understand.
"notibar" probably doesn't count ;)

[Ian Wen, 2016/01/29 02:38:43]

Done.

+
+        collection.removeCurrent(true);
+        assertTrue(onActionWasCalled());
+        assertTrue(collection.isEmpty());
+    }
+
+    @Test
+    @Feature({"Browser", "Snackbar"})
+    public void testAddNotOverride() throws Exception {
+        SnackbarCollection collection = new SnackbarCollection();
+        assertTrue(collection.isEmpty());
+
+        Snackbar actionBar = makeActionSnackbar();
+        collection.add(actionBar);
+        assertFalse(collection.isEmpty());
+        assertEquals(actionBar, collection.getCurrent());
+
+        Snackbar notiBar = makeNotificationSnackbar();
+        collection.add(notiBar);
+        assertFalse(onDismissWasCalled());

[newt (away), 2016/01/28 17:32:00]

It's confusing which snackbar onDismiss() might be associated with. Using
mockito (as explained below) and using separate SnackbarControllers for each
snackbar would make this clearer.

+        assertFalse(collection.isEmpty());
+        assertEquals("ActionBar was overriden by notiBar!", actionBar, collection.getCurrent());
+
+        collection.removeCurrent(true);
+        assertTrue(onActionWasCalled());
+        assertFalse(collection.isEmpty());
+        assertEquals(notiBar, collection.getCurrent());
+
+        collection.removeCurrent(true);
+        assertTrue(onActionWasCalled());
+        assertTrue(collection.isEmpty());
+    }
+
+    @Test
+    @Feature({"Browser", "Snackbar"})
+    public void testClear() throws Exception {
+        SnackbarCollection collection = new SnackbarCollection();
+        for (int i = 0; i < 3; i++) {
+            collection.add(makeActionSnackbar());
+            collection.add(makeNotificationSnackbar());
+        }
+        assertFalse(collection.isEmpty());
+
+        collection.clear();
+        assertTrue(collection.isEmpty());
+    }
+
+    @Test
+    @Feature({"Browser", "Snackbar"})
+    public void testRemoveMatchingSnackbars() throws Exception {
+        SnackbarCollection collection = new SnackbarCollection();
+        for (int i = 0; i < 3; i++) {
+            collection.add(makeActionSnackbar());
+            collection.add(makeNotificationSnackbar());
+        }
+        SnackbarController anotherController = new SnackbarController() {
+            @Override
+            public void onDismissNoAction(Object actionData) {}
+
+            @Override
+            public void onAction(Object actionData) {}
+        };
+        for (int i = 0; i < 3; i++) {
+            collection.add(makeActionSnackbar(anotherController));
+            collection.add(makeNotificationSnackbar(anotherController));
+        }
+
+        collection.removeMatchingSnackbars(this);
+        while (!collection.isEmpty()) {
+            Snackbar removed = collection.removeCurrent(true);
+            assertEquals(anotherController, removed.getController());
+        }
+    }
+
+    @Test
+    @Feature({"Browser", "Snackbar"})
+    public void testRemoveMatchingSnackbarsWithData() throws Exception {
+        SnackbarCollection collection = new SnackbarCollection();
+        for (int i = 0; i < 3; i++) {
+            collection.add(makeActionSnackbar().setAction(ACTION_TITLE, i));
+            collection.add(makeNotificationSnackbar().setAction(NOTIFICATION_TITLE, i));
+        }
+        SnackbarController anotherController = new SnackbarController() {
+            @Override
+            public void onDismissNoAction(Object actionData) {}
+
+            @Override
+            public void onAction(Object actionData) {}
+        };
+        for (int i = 0; i < 3; i++) {
+            collection.add(makeActionSnackbar(anotherController).setAction(ACTION_TITLE, i));
+            collection.add(
+                    makeNotificationSnackbar(anotherController).setAction(NOTIFICATION_TITLE, i));
+        }
+
+        final Integer dataToRemove = 0;
+        collection.removeMatchingSnackbars(this, dataToRemove);
+        while (!collection.isEmpty()) {
+            Snackbar removed = collection.removeCurrent(true);
+            assertFalse(this == removed.getController()
+                    && dataToRemove.equals(removed.getActionData()));
+        }
+    }
+
+    @Override
+    public void onAction(Object actionData) {
+        mActionCalled = true;
+    }
+
+    @Override
+    public void onDismissNoAction(Object actionData) {
+        mDismissCalled = true;
+    }
+
+    private boolean onActionWasCalled() {

[newt (away), 2016/01/28 17:32:00]

You could use Mockito to mock out a SnackbarController. Something like:

  SnackbarController controller = mock(SnackbarController.class);
  verify(controller, times(1)).onAction(null);

[Ian Wen, 2016/01/29 02:38:43]

Done.

+        boolean oldValue = mActionCalled;
+        mActionCalled = false;

[newt (away), 2016/01/28 17:32:00]

Resetting these values inside a method whose name indicates that it's a pure
getter is a bit suspect. I definitely would advise against it for production
code; even for test code, it's confusing.

Using mockito is one way around this issue. Or you could add separate methods
for resetting these values. Or you could change the method name to indicate that
it both reads and resets the value.

[Ian Wen, 2016/01/29 02:38:43]

Done.

+        return oldValue;
+    }
+
+    private boolean onDismissWasCalled() {
+        boolean oldValue = mDismissCalled;
+        mDismissCalled = false;
+        return oldValue;
+    }
+
+    private Snackbar makeActionSnackbar(SnackbarController controller) {
+        return Snackbar.make(ACTION_TITLE, controller, Snackbar.TYPE_ACTION);
+    }
+
+    private Snackbar makeNotificationSnackbar(SnackbarController controller) {
+        return Snackbar.make(NOTIFICATION_TITLE, controller, Snackbar.TYPE_NOTIFICATION);
+    }
+
+    private Snackbar makeActionSnackbar() {
+        return makeActionSnackbar(this);
+    }
+
+    private Snackbar makeNotificationSnackbar() {
+        return makeNotificationSnackbar(this);
+    }
+}