Added ToHashSetAsync<T> Extension methods on IQueryable<T>

src/EFCore/Extensions/EntityFrameworkQueryableExtensions.cs

@@ -2337,6 +2337,84 @@ public static async Task<TSource[]> ToArrayAsync<TSource>(
 
  #endregion
 
+ #region ToHashSet
+
+ /// <summary>
+ /// Asynchronously creates a <see cref="HashSet{T}" /> from an <see cref="IQueryable{T}" /> by enumerating it
+ /// asynchronously.
+ /// </summary>
+ /// <remarks>
+ /// <para>
+ /// Multiple active operations on the same context instance are not supported. Use <see langword="await" /> to ensure
+ /// that any asynchronous operations have completed before calling another method on this context.
+ /// See <see href="https://aka.ms/efcore-docs-threading">Avoiding DbContext threading issues</see> for more information and examples.
+ /// </para>
+ /// <para>
+ /// See <see href="https://aka.ms/efcore-docs-async-linq">Querying data with EF Core</see> for more information and examples.
+ /// </para>
+ /// </remarks>
+ /// <typeparam name="TSource">The type of the elements of <paramref name="source" />.</typeparam>
+ /// <param name="source">An <see cref="IQueryable{T}" /> to create a set from.</param>
+ /// <param name="cancellationToken">A <see cref="CancellationToken" /> to observe while waiting for the task to complete.</param>
+ /// <returns>
+ /// A task that represents the asynchronous operation.
+ /// The task result contains a <see cref="HashSet{T}" /> that contains elements from the input sequence.
+ /// </returns>
+ /// <exception cref="ArgumentNullException"><paramref name="source" /> is <see langword="null" />.</exception>
+ /// <exception cref="OperationCanceledException">If the <see cref="CancellationToken" /> is canceled.</exception>
+ public static async Task<HashSet<TSource>> ToHashSetAsync<TSource>(
+ this IQueryable<TSource> source,
+ CancellationToken cancellationToken = default)
+ {
+ var set = new HashSet<TSource>();
+ await foreach (var element in source.AsAsyncEnumerable().WithCancellation(cancellationToken).ConfigureAwait(false))
+ {
+ set.Add(element);
+ }
+
+ return set;
+ }
+
+ /// <summary>
+ /// Asynchronously creates a <see cref="HashSet{T}" /> from an <see cref="IQueryable{T}" /> by enumerating it
+ /// asynchronously.
+ /// </summary>
+ /// <remarks>
+ /// <para>
+ /// Multiple active operations on the same context instance are not supported. Use <see langword="await" /> to ensure
+ /// that any asynchronous operations have completed before calling another method on this context.
+ /// See <see href="https://aka.ms/efcore-docs-threading">Avoiding DbContext threading issues</see> for more information and examples.
+ /// </para>
+ /// <para>
+ /// See <see href="https://aka.ms/efcore-docs-async-linq">Querying data with EF Core</see> for more information and examples.
+ /// </para>
+ /// </remarks>
+ /// <typeparam name="TSource">The type of the elements of <paramref name="source" />.</typeparam>
+ /// <param name="source">An <see cref="IQueryable{T}" /> to create a set from.</param>
+ /// <param name="comparer">The <see cref="IEqualityComparer{T}"/> implementation to use when comparing values in the set, or null to use the default <see cref="EqualityComparer{T}"/> implementation for the set type.</param>
+ /// <param name="cancellationToken">A <see cref="CancellationToken" /> to observe while waiting for the task to complete.</param>
+ /// <returns>
+ /// A task that represents the asynchronous operation.
+ /// The task result contains a <see cref="HashSet{T}" /> that contains elements from the input sequence.
+ /// </returns>
+ /// <exception cref="ArgumentNullException"><paramref name="source" /> is <see langword="null" />.</exception>
+ /// <exception cref="OperationCanceledException">If the <see cref="CancellationToken" /> is canceled.</exception>
+ public static async Task<HashSet<TSource>> ToHashSetAsync<TSource>(
+ this IQueryable<TSource> source,
+ IEqualityComparer<TSource>? comparer,
+ CancellationToken cancellationToken = default)
+ {
+ var set = new HashSet<TSource>(comparer);
+ await foreach (var element in source.AsAsyncEnumerable().WithCancellation(cancellationToken).ConfigureAwait(false))
+ {
+ set.Add(element);
+ }
+
+ return set;
+ }
+
+ #endregion
+
  #region Include
 
  internal static readonly MethodInfo IncludeMethodInfo
@@ -2834,8 +2912,8 @@ source.Provider is EntityQueryProvider
  /// </exception>
  public static IQueryable<T> TagWithCallSite<T>(
  this IQueryable<T> source,
- [NotParameterized][CallerFilePath] string? filePath = null,
- [NotParameterized][CallerLineNumber] int lineNumber = 0)
+ [NotParameterized][CallerFilePath] string? filePath = null,
+ [NotParameterized][CallerLineNumber] int lineNumber = 0)
  => source.Provider is EntityQueryProvider
  ? source.Provider.CreateQuery<T>(
  Expression.Call(

test/EFCore.Tests/Extensions/QueryableExtensionsTest.cs

@@ -298,6 +298,10 @@ await SourceNonAsyncEnumerableTest<int>(
  () => Source().ToDictionaryAsync(e => e, e => e, ReferenceEqualityComparer.Instance));
  await SourceNonAsyncEnumerableTest<int>(
  () => Source().ToDictionaryAsync(e => e, e => e, ReferenceEqualityComparer.Instance, new CancellationToken()));
+ await SourceNonAsyncEnumerableTest<int>(() => Source().ToHashSetAsync());
+ await SourceNonAsyncEnumerableTest<int>(() => Source().ToHashSetAsync(EqualityComparer<int>.Default));
+ await SourceNonAsyncEnumerableTest<int>(
+ () => Source().ToHashSetAsync(EqualityComparer<int>.Default, new CancellationToken()));
  await SourceNonAsyncEnumerableTest<int>(() => Source().ToListAsync());
 
  Assert.Equal(