recyclerview-selection/tests/java/androidx/recyclerview/selection/DefaultSelectionHelper_SingleSelectTest.java

/*
 * Copyright 2017 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package androidx.recyclerview.selection;

import static org.junit.Assert.fail;

import android.support.test.filters.SmallTest;
import android.support.test.runner.AndroidJUnit4;

import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;

import java.util.List;

import androidx.recyclerview.selection.testing.SelectionProbe;
import androidx.recyclerview.selection.testing.TestAdapter;
import androidx.recyclerview.selection.testing.TestItemKeyProvider;
import androidx.recyclerview.selection.testing.TestSelectionObserver;

@RunWith(AndroidJUnit4.class)
@SmallTest
public class DefaultSelectionHelper_SingleSelectTest {

    private List<String> mItems;
    private SelectionHelper<String> mHelper;
    private TestSelectionObserver<String> mListener;
    private SelectionProbe mSelection;

    @Before
    public void setUp() throws Exception {
        mItems = TestAdapter.createItemList(100);
        mListener = new TestSelectionObserver<>();
        TestAdapter adapter = new TestAdapter();
        adapter.updateTestModelIds(mItems);

        ItemKeyProvider<String> keyProvider =
                new TestItemKeyProvider<>(ItemKeyProvider.SCOPE_MAPPED, adapter);
        mHelper = new DefaultSelectionHelper<>(
                keyProvider,
                SelectionPredicates.selectSingleAnything());
        EventBridge.install(adapter, mHelper, keyProvider);

        mHelper.addObserver(mListener);

        mSelection = new SelectionProbe(mHelper);
    }

    @Test
    public void testSimpleSelect() {
        mHelper.select(mItems.get(3));
        mHelper.select(mItems.get(4));
        mListener.assertSelectionChanged();
        mSelection.assertSelection(4);
    }

    @Test
    public void testRangeSelectionNotEstablished() {
        mHelper.select(mItems.get(3));
        mListener.reset();

        try {
            mHelper.extendRange(10);
            fail("Should have thrown.");
        } catch (Exception expected) { }

        mListener.assertSelectionUnchanged();
        mSelection.assertSelection(3);
    }

    @Test
    public void testProvisionalRangeSelection_Ignored() {
        mHelper.startRange(13);
        mHelper.extendProvisionalRange(15);
        mSelection.assertSelection(13);
    }
}