Kit.Core/LibExternal/System.Reactive/Linq/Observable/ToDictionary.cs

77 lines
2.7 KiB
C#

// 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.Collections.Generic;
namespace System.Reactive.Linq.ObservableImpl
{
internal sealed class ToDictionary<TSource, TKey, TElement> : Producer<IDictionary<TKey, TElement>, ToDictionary<TSource, TKey, TElement>._>
where TKey : notnull
{
private readonly IObservable<TSource> _source;
private readonly Func<TSource, TKey> _keySelector;
private readonly Func<TSource, TElement> _elementSelector;
private readonly IEqualityComparer<TKey> _comparer;
public ToDictionary(IObservable<TSource> source, Func<TSource, TKey> keySelector, Func<TSource, TElement> elementSelector, IEqualityComparer<TKey> comparer)
{
_source = source;
_keySelector = keySelector;
_elementSelector = elementSelector;
_comparer = comparer;
}
protected override _ CreateSink(IObserver<IDictionary<TKey, TElement>> observer) => new(this, observer);
protected override void Run(_ sink) => sink.Run(_source);
internal sealed class _ : Sink<TSource, IDictionary<TKey, TElement>>
{
private readonly Func<TSource, TKey> _keySelector;
private readonly Func<TSource, TElement> _elementSelector;
private Dictionary<TKey, TElement> _dictionary;
public _(ToDictionary<TSource, TKey, TElement> parent, IObserver<IDictionary<TKey, TElement>> observer)
: base(observer)
{
_keySelector = parent._keySelector;
_elementSelector = parent._elementSelector;
_dictionary = new Dictionary<TKey, TElement>(parent._comparer);
}
public override void OnNext(TSource value)
{
try
{
_dictionary.Add(_keySelector(value), _elementSelector(value));
}
catch (Exception ex)
{
Cleanup();
ForwardOnError(ex);
}
}
public override void OnError(Exception error)
{
Cleanup();
ForwardOnError(error);
}
public override void OnCompleted()
{
var dictionary = _dictionary;
Cleanup();
ForwardOnNext(dictionary);
ForwardOnCompleted();
}
private void Cleanup()
{
_dictionary = null!;
}
}
}
}