Use source generator to generate FirstOrDefaultAsync 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?> FirstOrDefaultAsync<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, ValueTask<bool>> predicate, CancellationToken cancellationToken = default) => FirstOrDefaultAwaitAsyncCore<TSource>(source, predicate, cancellationToken);
         public static Task ForEachAsync<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, Task> action, CancellationToken cancellationToken = default) => ForEachAwaitAsyncCore<TSource>(source, action, cancellationToken);
         public static Task ForEachAsync<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, int, Task> action, CancellationToken cancellationToken = default) => ForEachAwaitAsyncCore<TSource>(source, action, cancellationToken);
         public static IAsyncEnumerable<IAsyncGrouping<TKey, TSource>> GroupBy<TSource, TKey>(this IAsyncEnumerable<TSource> source, Func<TSource, ValueTask<TKey>> keySelector) => GroupByAwaitCore<TSource, TKey>(source, keySelector);
@@ -94,7 +93,6 @@ 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?> FirstOrDefaultAsync<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, CancellationToken, ValueTask<bool>> predicate, CancellationToken cancellationToken = default) => FirstOrDefaultAwaitWithCancellationAsyncCore<TSource>(source, predicate, cancellationToken);
         public static Task ForEachAsync<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, CancellationToken, Task> action, CancellationToken cancellationToken) => ForEachAwaitWithCancellationAsyncCore<TSource>(source, action, cancellationToken);
         public static Task ForEachAsync<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, int, CancellationToken, Task> action, CancellationToken cancellationToken) => ForEachAwaitWithCancellationAsyncCore<TSource>(source, action, cancellationToken);
         public static IAsyncEnumerable<IAsyncGrouping<TKey, TSource>> GroupBy<TSource, TKey>(this IAsyncEnumerable<TSource> source, Func<TSource, CancellationToken, ValueTask<TKey>> keySelector) => GroupByAwaitWithCancellationCore<TSource, TKey>(source, keySelector);
@@ -177,17 +175,6 @@ 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 first element of an async-enumerable sequence that satisfies the condition in the predicate, or a default value if no element satisfies the condition in the predicate.
-        /// </summary>
-        /// <typeparam name="TSource">The type of element in the sequence.</typeparam>
-        /// <param name="source">Source async-enumerable sequence.</param>
-        /// <param name="predicate">An asynchronous predicate to invoke and await on each element of the sequence.</param>
-        /// <param name="cancellationToken">An optional cancellation token for cancelling the sequence at any time.</param>
-        /// <returns>A ValueTask containing the first element in the sequence that satisfies the predicate, or a default value if no element satisfies the predicate.</returns>
-        /// <exception cref="ArgumentNullException"><paramref name="source"/> or <paramref name="predicate"/> is <see langword="null"/>.</exception>
-        public static ValueTask<TSource?> FirstOrDefaultAwaitAsync<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, ValueTask<bool>> predicate, CancellationToken cancellationToken = default) => FirstOrDefaultAwaitAsyncCore<TSource>(source, predicate, cancellationToken);
-
         /// <summary>
         /// Invokes and awaits an asynchronous action on each element in the source sequence, and returns a task that is signaled when the sequence terminates.
         /// </summary>
@@ -1112,7 +1099,6 @@ 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?> FirstOrDefaultAwaitWithCancellationAsync<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, CancellationToken, ValueTask<bool>> predicate, CancellationToken cancellationToken = default) => FirstOrDefaultAwaitWithCancellationAsyncCore<TSource>(source, predicate, cancellationToken);
         public static Task ForEachAwaitWithCancellationAsync<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, CancellationToken, Task> action, CancellationToken cancellationToken) => ForEachAwaitWithCancellationAsyncCore<TSource>(source, action, cancellationToken);
         public static Task ForEachAwaitWithCancellationAsync<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, int, CancellationToken, Task> action, CancellationToken cancellationToken) => ForEachAwaitWithCancellationAsyncCore<TSource>(source, action, cancellationToken);
         public static IAsyncEnumerable<IAsyncGrouping<TKey, TSource>> GroupByAwaitWithCancellation<TSource, TKey>(this IAsyncEnumerable<TSource> source, Func<TSource, CancellationToken, ValueTask<TKey>> keySelector) => GroupByAwaitWithCancellationCore<TSource, TKey>(source, keySelector);

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

@@ -59,7 +59,17 @@ namespace System.Linq
             }
         }
 
-        internal static ValueTask<TSource?> FirstOrDefaultAwaitAsyncCore<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, ValueTask<bool>> predicate, CancellationToken cancellationToken = default)
+        /// <summary>
+        /// Returns the first element of an async-enumerable sequence that satisfies the condition in the predicate, or a default value if no element satisfies the condition in the predicate.
+        /// </summary>
+        /// <typeparam name="TSource">The type of element in the sequence.</typeparam>
+        /// <param name="source">Source async-enumerable sequence.</param>
+        /// <param name="predicate">An asynchronous predicate to invoke and await on each element of the sequence.</param>
+        /// <param name="cancellationToken">An optional cancellation token for cancelling the sequence at any time.</param>
+        /// <returns>A ValueTask containing the first element in the sequence that satisfies the predicate, or a default value if no element satisfies the predicate.</returns>
+        /// <exception cref="ArgumentNullException"><paramref name="source"/> or <paramref name="predicate"/> is <see langword="null"/>.</exception>
+        [GenerateAsyncOverload]
+        private static ValueTask<TSource?> FirstOrDefaultAwaitAsyncCore<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, ValueTask<bool>> predicate, CancellationToken cancellationToken = default)
         {
             if (source == null)
                 throw Error.ArgumentNull(nameof(source));
@@ -77,7 +87,8 @@ namespace System.Linq
         }
 
 #if !NO_DEEP_CANCELLATION
-        internal static ValueTask<TSource?> FirstOrDefaultAwaitWithCancellationAsyncCore<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, CancellationToken, ValueTask<bool>> predicate, CancellationToken cancellationToken = default)
+        [GenerateAsyncOverload]
+        private static ValueTask<TSource?> FirstOrDefaultAwaitWithCancellationAsyncCore<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, CancellationToken, ValueTask<bool>> predicate, CancellationToken cancellationToken = default)
         {
             if (source == null)
                 throw Error.ArgumentNull(nameof(source));