dotnet/tests/CommunityToolkit.Common.UnitTests/Collections/ReadOnlyObservableGroupTests.cs

// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.

using System;
using System.Collections.ObjectModel;
using System.Collections.Specialized;
using System.Linq;
using CommunityToolkit.Common.Collections;
using Microsoft.VisualStudio.TestTools.UnitTesting;

namespace CommunityToolkit.Common.UnitTests.Collections;

[TestClass]
public class ReadOnlyObservableGroupTests
{
    [TestMethod]
    public void Ctor_WithKeyAndOBservableCollection_ShouldHaveExpectedInitialState()
    {
        ObservableCollection<int>? source = new(new[] { 1, 2, 3 });
        ReadOnlyObservableGroup<string, int>? group = new("key", source);

        Assert.AreEqual(group.Key, "key");
        CollectionAssert.AreEqual(group, new[] { 1, 2, 3 });
    }

    [TestMethod]
    public void Ctor_ObservableGroup_ShouldHaveExpectedInitialState()
    {
        int[]? source = new[] { 1, 2, 3 };
        ObservableGroup<string, int>? sourceGroup = new("key", source);
        ReadOnlyObservableGroup<string, int>? group = new(sourceGroup);

        Assert.AreEqual(group.Key, "key");
        CollectionAssert.AreEqual(group, new[] { 1, 2, 3 });
    }

    [TestMethod]
    public void Ctor_WithKeyAndCollection_ShouldHaveExpectedInitialState()
    {
        int[]? source = new[] { 1, 2, 3 };
        ReadOnlyObservableGroup<string, int>? group = new("key", source);

        Assert.AreEqual(group.Key, "key");
        CollectionAssert.AreEqual(group, new[] { 1, 2, 3 });
    }

    [TestMethod]
    public void Add_ShouldRaiseEvent()
    {
        bool collectionChangedEventRaised = false;
        int[]? source = new[] { 1, 2, 3 };
        ObservableGroup<string, int>? sourceGroup = new("key", source);
        ReadOnlyObservableGroup<string, int>? group = new(sourceGroup);
        ((INotifyCollectionChanged)group).CollectionChanged += (s, e) => collectionChangedEventRaised = true;

        sourceGroup.Add(4);

        Assert.AreEqual(group.Key, "key");
        CollectionAssert.AreEqual(group, new[] { 1, 2, 3, 4 });

        Assert.IsTrue(collectionChangedEventRaised);
    }

    [TestMethod]
    public void Update_ShouldRaiseEvent()
    {
        bool collectionChangedEventRaised = false;
        int[]? source = new[] { 1, 2, 3 };
        ObservableGroup<string, int>? sourceGroup = new("key", source);
        ReadOnlyObservableGroup<string, int>? group = new(sourceGroup);
        ((INotifyCollectionChanged)group).CollectionChanged += (s, e) => collectionChangedEventRaised = true;

        sourceGroup[1] = 4;

        Assert.AreEqual(group.Key, "key");
        CollectionAssert.AreEqual(group, new[] { 1, 4, 3 });

        Assert.IsTrue(collectionChangedEventRaised);
    }

    [TestMethod]
    public void Remove_ShouldRaiseEvent()
    {
        bool collectionChangedEventRaised = false;
        int[]? source = new[] { 1, 2, 3 };
        ObservableGroup<string, int>? sourceGroup = new("key", source);
        ReadOnlyObservableGroup<string, int>? group = new(sourceGroup);
        ((INotifyCollectionChanged)group).CollectionChanged += (s, e) => collectionChangedEventRaised = true;

        _ = sourceGroup.Remove(1);

        Assert.AreEqual(group.Key, "key");
        CollectionAssert.AreEqual(group, new[] { 2, 3 });

        Assert.IsTrue(collectionChangedEventRaised);
    }

    [TestMethod]
    public void Clear_ShouldRaiseEvent()
    {
        bool collectionChangedEventRaised = false;
        int[]? source = new[] { 1, 2, 3 };
        ObservableGroup<string, int>? sourceGroup = new("key", source);
        ReadOnlyObservableGroup<string, int>? group = new(sourceGroup);
        ((INotifyCollectionChanged)group).CollectionChanged += (s, e) => collectionChangedEventRaised = true;

        sourceGroup.Clear();

        Assert.AreEqual(group.Key, "key");
        CollectionAssert.AreEqual(group, Array.Empty<int>());

        Assert.IsTrue(collectionChangedEventRaised);
    }

    [DataTestMethod]
    [DataRow(0)]
    [DataRow(3)]
    public void IReadOnlyObservableGroup_ShouldReturnExpectedValues(int count)
    {
        ObservableGroup<string, int>? sourceGroup = new("key", Enumerable.Range(0, count));
        ReadOnlyObservableGroup<string, int>? group = new(sourceGroup);
        IReadOnlyObservableGroup? iReadOnlyObservableGroup = (IReadOnlyObservableGroup)group;

        Assert.AreEqual(iReadOnlyObservableGroup.Key, "key");
        Assert.AreEqual(iReadOnlyObservableGroup.Count, count);
    }
}