Add missing AverageAsync overloads supporting async selectors (#2278)

Ix.NET/Source/System.Interactive.Async/System/Linq/Operators/Average.Generated.tt

@@ -144,6 +144,166 @@ else
                 }
 <#
 }
+#>
+            }
+        }
+
+        /// <summary>
+        /// Computes the average of an async-enumerable sequence of <see cref="int"/> values that are obtained by invoking an asynchronous transform function on each element of the source sequence and awaiting the result.
+        /// </summary>
+        /// <typeparam name="TSource">The type of elements in the source sequence.</typeparam>
+        /// <param name="source">An async-enumerable sequence of values to compute the average of.</param>
+        /// <param name="selector">A transform function to invoke and await on each element of the source sequence.</param>
+        /// <param name="cancellationToken">An optional cancellation token for cancelling the sequence at any time.</param>
+        /// <returns>A ValueTask containing the average of the sequence of values.</returns>
+        /// <exception cref="ArgumentNullException"><paramref name="source"/> or <paramref name="selector"/> is <see langword="null"/>.</exception>
+        /// <exception cref="InvalidOperationException">The source sequence is empty.</exception>
+        /// <remarks>The return type of this operator differs from the corresponding operator on IEnumerable in order to retain asynchronous behavior.</remarks>
+        [GenerateAsyncOverload]
+        private static ValueTask<<#=o.res#>> AverageAsyncCore<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, ValueTask<<#=o.type#>>> selector, CancellationToken cancellationToken = default)
+        {
+            if (source == null)
+                throw Error.ArgumentNull(nameof(source));
+            if (selector == null)
+                throw Error.ArgumentNull(nameof(selector));
+
+            return Core(source, selector, cancellationToken);
+
+            static async ValueTask<<#=o.res#>> Core(IAsyncEnumerable<TSource> source, Func<TSource, ValueTask<<#=o.type#>>> selector, CancellationToken cancellationToken)
+            {
+<#
+if (isNullable)
+{
+#>
+                await using (var e = source.GetConfiguredAsyncEnumerator(cancellationToken, false))
+                {
+                    while (await e.MoveNextAsync())
+                    {
+                        var v = await selector(e.Current).ConfigureAwait(false);
+                        if (v.HasValue)
+                        {
+                            <#=o.sum#> sum = v.GetValueOrDefault();
+                            long count = 1;
+                            checked
+                            {
+                                while (await e.MoveNextAsync())
+                                {
+                                    v = await selector(e.Current).ConfigureAwait(false);
+                                    if (v.HasValue)
+                                    {
+                                        sum += v.GetValueOrDefault();
+                                        ++count;
+                                    }
+                                }
+                            }
+
+                            return <#=res#>;
+                        }
+                    }
+                }
+
+                return null;
+<#
+}
+else
+{
+#>
+                await using (var e = source.GetConfiguredAsyncEnumerator(cancellationToken, false))
+                {
+                    if (!await e.MoveNextAsync())
+                    {
+                        throw Error.NoElements();
+                    }
+
+                    <#=o.sum#> sum = await selector(e.Current).ConfigureAwait(false);
+                    long count = 1;
+                    checked
+                    {
+                        while (await e.MoveNextAsync())
+                        {
+                            sum += await selector(e.Current).ConfigureAwait(false);
+                            ++count;
+                        }
+                    }
+
+                    return <#=res#>;
+                }
+<#
+}
+#>
+            }
+        }
+        [GenerateAsyncOverload]
+        private static ValueTask<<#=o.res#>> AverageAsyncCore<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, CancellationToken, ValueTask<<#=o.type#>>> selector, CancellationToken cancellationToken = default)
+        {
+            if (source == null)
+                throw Error.ArgumentNull(nameof(source));
+            if (selector == null)
+                throw Error.ArgumentNull(nameof(selector));
+
+            return Core(source, selector, cancellationToken);
+
+            static async ValueTask<<#=o.res#>> Core(IAsyncEnumerable<TSource> source, Func<TSource, CancellationToken, ValueTask<<#=o.type#>>> selector, CancellationToken cancellationToken)
+            {
+<#
+if (isNullable)
+{
+#>
+                await using (var e = source.GetConfiguredAsyncEnumerator(cancellationToken, false))
+                {
+                    while (await e.MoveNextAsync())
+                    {
+                        var v = await selector(e.Current, cancellationToken).ConfigureAwait(false);
+                        if (v.HasValue)
+                        {
+                            <#=o.sum#> sum = v.GetValueOrDefault();
+                            long count = 1;
+                            checked
+                            {
+                                while (await e.MoveNextAsync())
+                                {
+                                    v = await selector(e.Current, cancellationToken).ConfigureAwait(false);
+                                    if (v.HasValue)
+                                    {
+                                        sum += v.GetValueOrDefault();
+                                        ++count;
+                                    }
+                                }
+                            }
+
+                            return <#=res#>;
+                        }
+                    }
+                }
+
+                return null;
+<#
+}
+else
+{
+#>
+                await using (var e = source.GetConfiguredAsyncEnumerator(cancellationToken, false))
+                {
+                    if (!await e.MoveNextAsync())
+                    {
+                        throw Error.NoElements();
+                    }
+
+                    <#=o.sum#> sum = await selector(e.Current, cancellationToken).ConfigureAwait(false);
+                    long count = 1;
+                    checked
+                    {
+                        while (await e.MoveNextAsync())
+                        {
+                            sum += await selector(e.Current, cancellationToken).ConfigureAwait(false);
+                            ++count;
+                        }
+                    }
+
+                    return <#=res#>;
+                }
+<#
+}
 #>
             }
         }

Ix.NET/Source/Tests.System.Interactive.ApiApprovals/Api/ApiApprovalTests.SystemInteractiveAsync.verified.cs

@@ -10,6 +10,16 @@ namespace System.Linq
         public static System.Collections.Generic.IAsyncEnumerable<TSource> Amb<TSource>(this System.Collections.Generic.IEnumerable<System.Collections.Generic.IAsyncEnumerable<TSource>> sources) { }
         public static System.Collections.Generic.IAsyncEnumerable<TSource> Amb<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> first, System.Collections.Generic.IAsyncEnumerable<TSource> second) { }
         public static System.Collections.Generic.IAsyncEnumerable<TSource> AsAsyncEnumerable<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source) { }
+        public static System.Threading.Tasks.ValueTask<decimal> AverageAsync<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, System.Func<TSource, System.Threading.Tasks.ValueTask<decimal>> selector, System.Threading.CancellationToken cancellationToken = default) { }
+        public static System.Threading.Tasks.ValueTask<decimal?> AverageAsync<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, System.Func<TSource, System.Threading.Tasks.ValueTask<decimal?>> selector, System.Threading.CancellationToken cancellationToken = default) { }
+        public static System.Threading.Tasks.ValueTask<double> AverageAsync<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, System.Func<TSource, System.Threading.Tasks.ValueTask<double>> selector, System.Threading.CancellationToken cancellationToken = default) { }
+        public static System.Threading.Tasks.ValueTask<double?> AverageAsync<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, System.Func<TSource, System.Threading.Tasks.ValueTask<double?>> selector, System.Threading.CancellationToken cancellationToken = default) { }
+        public static System.Threading.Tasks.ValueTask<float> AverageAsync<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, System.Func<TSource, System.Threading.Tasks.ValueTask<float>> selector, System.Threading.CancellationToken cancellationToken = default) { }
+        public static System.Threading.Tasks.ValueTask<float?> AverageAsync<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, System.Func<TSource, System.Threading.Tasks.ValueTask<float?>> selector, System.Threading.CancellationToken cancellationToken = default) { }
+        public static System.Threading.Tasks.ValueTask<double> AverageAsync<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, System.Func<TSource, System.Threading.Tasks.ValueTask<int>> selector, System.Threading.CancellationToken cancellationToken = default) { }
+        public static System.Threading.Tasks.ValueTask<double?> AverageAsync<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, System.Func<TSource, System.Threading.Tasks.ValueTask<int?>> selector, System.Threading.CancellationToken cancellationToken = default) { }
+        public static System.Threading.Tasks.ValueTask<double> AverageAsync<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, System.Func<TSource, System.Threading.Tasks.ValueTask<long>> selector, System.Threading.CancellationToken cancellationToken = default) { }
+        public static System.Threading.Tasks.ValueTask<double?> AverageAsync<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, System.Func<TSource, System.Threading.Tasks.ValueTask<long?>> selector, System.Threading.CancellationToken cancellationToken = default) { }
         public static System.Threading.Tasks.ValueTask<decimal> AverageAsync<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, System.Func<TSource, decimal> selector, System.Threading.CancellationToken cancellationToken = default) { }
         public static System.Threading.Tasks.ValueTask<decimal?> AverageAsync<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, System.Func<TSource, decimal?> selector, System.Threading.CancellationToken cancellationToken = default) { }
         public static System.Threading.Tasks.ValueTask<double> AverageAsync<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, System.Func<TSource, double> selector, System.Threading.CancellationToken cancellationToken = default) { }
@@ -20,6 +30,16 @@ namespace System.Linq
         public static System.Threading.Tasks.ValueTask<double?> AverageAsync<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, System.Func<TSource, int?> selector, System.Threading.CancellationToken cancellationToken = default) { }
         public static System.Threading.Tasks.ValueTask<double> AverageAsync<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, System.Func<TSource, long> selector, System.Threading.CancellationToken cancellationToken = default) { }
         public static System.Threading.Tasks.ValueTask<double?> AverageAsync<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, System.Func<TSource, long?> selector, System.Threading.CancellationToken cancellationToken = default) { }
+        public static System.Threading.Tasks.ValueTask<decimal> AverageAsync<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, System.Func<TSource, System.Threading.CancellationToken, System.Threading.Tasks.ValueTask<decimal>> selector, System.Threading.CancellationToken cancellationToken = default) { }
+        public static System.Threading.Tasks.ValueTask<decimal?> AverageAsync<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, System.Func<TSource, System.Threading.CancellationToken, System.Threading.Tasks.ValueTask<decimal?>> selector, System.Threading.CancellationToken cancellationToken = default) { }
+        public static System.Threading.Tasks.ValueTask<double> AverageAsync<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, System.Func<TSource, System.Threading.CancellationToken, System.Threading.Tasks.ValueTask<double>> selector, System.Threading.CancellationToken cancellationToken = default) { }
+        public static System.Threading.Tasks.ValueTask<double?> AverageAsync<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, System.Func<TSource, System.Threading.CancellationToken, System.Threading.Tasks.ValueTask<double?>> selector, System.Threading.CancellationToken cancellationToken = default) { }
+        public static System.Threading.Tasks.ValueTask<float> AverageAsync<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, System.Func<TSource, System.Threading.CancellationToken, System.Threading.Tasks.ValueTask<float>> selector, System.Threading.CancellationToken cancellationToken = default) { }
+        public static System.Threading.Tasks.ValueTask<float?> AverageAsync<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, System.Func<TSource, System.Threading.CancellationToken, System.Threading.Tasks.ValueTask<float?>> selector, System.Threading.CancellationToken cancellationToken = default) { }
+        public static System.Threading.Tasks.ValueTask<double> AverageAsync<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, System.Func<TSource, System.Threading.CancellationToken, System.Threading.Tasks.ValueTask<int>> selector, System.Threading.CancellationToken cancellationToken = default) { }
+        public static System.Threading.Tasks.ValueTask<double?> AverageAsync<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, System.Func<TSource, System.Threading.CancellationToken, System.Threading.Tasks.ValueTask<int?>> selector, System.Threading.CancellationToken cancellationToken = default) { }
+        public static System.Threading.Tasks.ValueTask<double> AverageAsync<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, System.Func<TSource, System.Threading.CancellationToken, System.Threading.Tasks.ValueTask<long>> selector, System.Threading.CancellationToken cancellationToken = default) { }
+        public static System.Threading.Tasks.ValueTask<double?> AverageAsync<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, System.Func<TSource, System.Threading.CancellationToken, System.Threading.Tasks.ValueTask<long?>> selector, System.Threading.CancellationToken cancellationToken = default) { }
         public static System.Collections.Generic.IAsyncEnumerable<System.Collections.Generic.IList<TSource>> Buffer<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, int count) { }
         public static System.Collections.Generic.IAsyncEnumerable<System.Collections.Generic.IList<TSource>> Buffer<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, int count, int skip) { }
         public static System.Collections.Generic.IAsyncEnumerable<TSource> Catch<TSource>(params System.Collections.Generic.IAsyncEnumerable<TSource>[] sources) { }