Use source generator to generate LastAsync overloads

Ix.NET/Source/System.Linq.Async/System/Linq/AsyncEnumerable.AsyncOverloads.cs

@@ -11,7 +11,6 @@ namespace System.Linq
     partial class AsyncEnumerable
     {
 #if SUPPORT_FLAT_ASYNC_API
-        public static ValueTask<TSource> LastAsync<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, ValueTask<bool>> predicate, CancellationToken cancellationToken = default) => LastAwaitAsyncCore<TSource>(source, predicate, cancellationToken);
         public static ValueTask<TSource?> LastOrDefaultAsync<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, ValueTask<bool>> predicate, CancellationToken cancellationToken = default) => LastOrDefaultAwaitAsyncCore<TSource>(source, predicate, cancellationToken);
         public static ValueTask<long> LongCountAsync<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, ValueTask<bool>> predicate, CancellationToken cancellationToken = default) => LongCountAwaitAsyncCore<TSource>(source, predicate, cancellationToken);
         public static ValueTask<long> MaxAsync<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, ValueTask<long>> selector, CancellationToken cancellationToken = default) => MaxAwaitAsyncCore<TSource>(source, selector, cancellationToken);
@@ -79,7 +78,6 @@ namespace System.Linq
         public static IAsyncEnumerable<TResult> Zip<TFirst, TSecond, TResult>(this IAsyncEnumerable<TFirst> first, IAsyncEnumerable<TSecond> second, Func<TFirst, TSecond, ValueTask<TResult>> selector) => ZipAwaitCore<TFirst, TSecond, TResult>(first, second, selector);
 
 #if !NO_DEEP_CANCELLATION
-        public static ValueTask<TSource> LastAsync<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, CancellationToken, ValueTask<bool>> predicate, CancellationToken cancellationToken = default) => LastAwaitWithCancellationAsyncCore<TSource>(source, predicate, cancellationToken);
         public static ValueTask<TSource?> LastOrDefaultAsync<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, CancellationToken, ValueTask<bool>> predicate, CancellationToken cancellationToken = default) => LastOrDefaultAwaitWithCancellationAsyncCore<TSource>(source, predicate, cancellationToken);
         public static ValueTask<long> LongCountAsync<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, CancellationToken, ValueTask<bool>> predicate, CancellationToken cancellationToken = default) => LongCountAwaitWithCancellationAsyncCore<TSource>(source, predicate, cancellationToken);
         public static ValueTask<long> MaxAsync<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, CancellationToken, ValueTask<long>> selector, CancellationToken cancellationToken = default) => MaxAwaitWithCancellationAsyncCore<TSource>(source, selector, cancellationToken);
@@ -147,18 +145,6 @@ namespace System.Linq
         public static IAsyncEnumerable<TResult> Zip<TFirst, TSecond, TResult>(this IAsyncEnumerable<TFirst> first, IAsyncEnumerable<TSecond> second, Func<TFirst, TSecond, CancellationToken, ValueTask<TResult>> selector) => ZipAwaitWithCancellationCore<TFirst, TSecond, TResult>(first, second, selector);
 #endif
 #else
-        /// <summary>
-        /// Returns the last element of an async-enumerable sequence that satisfies the condition in the predicate.
-        /// </summary>
-        /// <typeparam name="TSource">The type of the elements in the source sequence.</typeparam>
-        /// <param name="source">Source async-enumerable sequence.</param>
-        /// <param name="predicate">An asynchronous predicate function to evaluate for elements in the source sequence.</param>
-        /// <param name="cancellationToken">The optional cancellation token to be used for cancelling the sequence at any time.</param>
-        /// <returns>ValueTask containing the last element in the async-enumerable sequence that satisfies the condition in the predicate.</returns>
-        /// <exception cref="ArgumentNullException"><paramref name="source"/> or <paramref name="predicate"/> is null.</exception>
-        /// <exception cref="InvalidOperationException">(Asynchronous) No element satisfies the condition in the predicate. -or- The source sequence is empty.</exception>
-        public static ValueTask<TSource> LastAwaitAsync<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, ValueTask<bool>> predicate, CancellationToken cancellationToken = default) => LastAwaitAsyncCore<TSource>(source, predicate, cancellationToken);
-
         /// <summary>
         /// Returns the last element of an async-enumerable sequence that satisfies the condition in the predicate, or a default value if no such element exists.
         /// </summary>
@@ -937,7 +923,6 @@ namespace System.Linq
         public static IAsyncEnumerable<TResult> ZipAwait<TFirst, TSecond, TResult>(this IAsyncEnumerable<TFirst> first, IAsyncEnumerable<TSecond> second, Func<TFirst, TSecond, ValueTask<TResult>> selector) => ZipAwaitCore<TFirst, TSecond, TResult>(first, second, selector);
 
 #if !NO_DEEP_CANCELLATION
-        public static ValueTask<TSource> LastAwaitWithCancellationAsync<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, CancellationToken, ValueTask<bool>> predicate, CancellationToken cancellationToken = default) => LastAwaitWithCancellationAsyncCore<TSource>(source, predicate, cancellationToken);
         public static ValueTask<TSource?> LastOrDefaultAwaitWithCancellationAsync<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, CancellationToken, ValueTask<bool>> predicate, CancellationToken cancellationToken = default) => LastOrDefaultAwaitWithCancellationAsyncCore<TSource>(source, predicate, cancellationToken);
         public static ValueTask<long> LongCountAwaitWithCancellationAsync<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, CancellationToken, ValueTask<bool>> predicate, CancellationToken cancellationToken = default) => LongCountAwaitWithCancellationAsyncCore<TSource>(source, predicate, cancellationToken);
         public static ValueTask<long> MaxAwaitWithCancellationAsync<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, CancellationToken, ValueTask<long>> selector, CancellationToken cancellationToken = default) => MaxAwaitWithCancellationAsyncCore<TSource>(source, selector, cancellationToken);

Ix.NET/Source/System.Linq.Async/System/Linq/Operators/Last.cs

@@ -61,7 +61,18 @@ namespace System.Linq
             }
         }
 
-        internal static ValueTask<TSource> LastAwaitAsyncCore<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, ValueTask<bool>> predicate, CancellationToken cancellationToken = default)
+        /// <summary>
+        /// Returns the last element of an async-enumerable sequence that satisfies the condition in the predicate.
+        /// </summary>
+        /// <typeparam name="TSource">The type of the elements in the source sequence.</typeparam>
+        /// <param name="source">Source async-enumerable sequence.</param>
+        /// <param name="predicate">An asynchronous predicate function to evaluate for elements in the source sequence.</param>
+        /// <param name="cancellationToken">The optional cancellation token to be used for cancelling the sequence at any time.</param>
+        /// <returns>ValueTask containing the last element in the async-enumerable sequence that satisfies the condition in the predicate.</returns>
+        /// <exception cref="ArgumentNullException"><paramref name="source"/> or <paramref name="predicate"/> is null.</exception>
+        /// <exception cref="InvalidOperationException">(Asynchronous) No element satisfies the condition in the predicate. -or- The source sequence is empty.</exception>
+        [GenerateAsyncOverload]
+        private static ValueTask<TSource> LastAwaitAsyncCore<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, ValueTask<bool>> predicate, CancellationToken cancellationToken = default)
         {
             if (source == null)
                 throw Error.ArgumentNull(nameof(source));
@@ -79,7 +90,8 @@ namespace System.Linq
         }
 
 #if !NO_DEEP_CANCELLATION
-        internal static ValueTask<TSource> LastAwaitWithCancellationAsyncCore<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, CancellationToken, ValueTask<bool>> predicate, CancellationToken cancellationToken = default)
+        [GenerateAsyncOverload]
+        private static ValueTask<TSource> LastAwaitWithCancellationAsyncCore<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, CancellationToken, ValueTask<bool>> predicate, CancellationToken cancellationToken = default)
         {
             if (source == null)
                 throw Error.ArgumentNull(nameof(source));