Merge pull request #1412 from danielcweber/IxAsyncNullability

Ix.Async nullability
dotnet · Nov 9, 2020 · 82bfabd · 82bfabd
2 parents c6998f7 + c97e772
commit 82bfabd
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Showing 6 changed files with 91 additions and 91 deletions.
diff --git a/Ix.NET/Source/System.Linq.Async.Queryable/System/Linq/AsyncQueryable.Generated.cs b/Ix.NET/Source/System.Linq.Async.Queryable/System/Linq/AsyncQueryable.Generated.cs
diff --git a/Ix.NET/Source/System.Linq.Async/System/Linq/AsyncEnumerable.AsyncOverloads.cs b/Ix.NET/Source/System.Linq.Async/System/Linq/AsyncEnumerable.AsyncOverloads.cs
diff --git a/Ix.NET/Source/System.Linq.Async/System/Linq/Operators/ElementAtOrDefault.cs b/Ix.NET/Source/System.Linq.Async/System/Linq/Operators/ElementAtOrDefault.cs
@@ -20,14 +20,14 @@ public static partial class AsyncEnumerable
         /// <returns>An async-enumerable sequence that produces the element at the specified position in the source sequence, or a default value if the index is outside the bounds of the source sequence.</returns>
         /// <exception cref="ArgumentNullException"><paramref name="source"/> is null.</exception>
         /// <exception cref="ArgumentOutOfRangeException"><paramref name="index"/> is less than zero.</exception>
-        public static ValueTask<TSource> ElementAtOrDefaultAsync<TSource>(this IAsyncEnumerable<TSource> source, int index, CancellationToken cancellationToken = default)
+        public static ValueTask<TSource?> ElementAtOrDefaultAsync<TSource>(this IAsyncEnumerable<TSource> source, int index, CancellationToken cancellationToken = default)
         {
             if (source == null)
                 throw Error.ArgumentNull(nameof(source));
 
             return Core(source, index, cancellationToken);
 
-            static async ValueTask<TSource> Core(IAsyncEnumerable<TSource> source, int index, CancellationToken cancellationToken)
+            static async ValueTask<TSource?> Core(IAsyncEnumerable<TSource> source, int index, CancellationToken cancellationToken)
             {
                 if (source is IAsyncPartition<TSource> p)
                 {
@@ -62,7 +62,7 @@ static async ValueTask<TSource> Core(IAsyncEnumerable<TSource> source, int index
                     }
                 }
 
-                return default!;
+                return default;
             }
         }
     }

diff --git a/Ix.NET/Source/System.Linq.Async/System/Linq/Operators/FirstOrDefault.cs b/Ix.NET/Source/System.Linq.Async/System/Linq/Operators/FirstOrDefault.cs
@@ -18,18 +18,18 @@ public static partial class AsyncEnumerable
         /// <param name="cancellationToken">The optional cancellation token to be used for cancelling the sequence at any time.</param>
         /// <returns>ValueTask containing the first element in the async-enumerable sequence, or a default value if no such element exists.</returns>
         /// <exception cref="ArgumentNullException"><paramref name="source"/> is null.</exception>
-        public static ValueTask<TSource> FirstOrDefaultAsync<TSource>(this IAsyncEnumerable<TSource> source, CancellationToken cancellationToken = default)
+        public static ValueTask<TSource?> FirstOrDefaultAsync<TSource>(this IAsyncEnumerable<TSource> source, CancellationToken cancellationToken = default)
         {
             if (source == null)
                 throw Error.ArgumentNull(nameof(source));
 
             return Core(source, cancellationToken);
 
-            static async ValueTask<TSource> Core(IAsyncEnumerable<TSource> source, CancellationToken cancellationToken)
+            static async ValueTask<TSource?> Core(IAsyncEnumerable<TSource> source, CancellationToken cancellationToken)
             {
                 var first = await TryGetFirst(source, cancellationToken).ConfigureAwait(false);
 
-                return first.HasValue ? first.Value : default!;
+                return first.HasValue ? first.Value : default;
             }
         }
 
@@ -42,7 +42,7 @@ static async ValueTask<TSource> Core(IAsyncEnumerable<TSource> source, Cancellat
         /// <param name="cancellationToken">The optional cancellation token to be used for cancelling the sequence at any time.</param>
         /// <returns>ValueTask containing the first element in the async-enumerable sequence that satisfies the condition in the predicate, or a default value if no such element exists.</returns>
         /// <exception cref="ArgumentNullException"><paramref name="source"/> or <paramref name="predicate"/> is null.</exception>
-        public static ValueTask<TSource> FirstOrDefaultAsync<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, bool> predicate, CancellationToken cancellationToken = default)
+        public static ValueTask<TSource?> FirstOrDefaultAsync<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, bool> predicate, CancellationToken cancellationToken = default)
         {
             if (source == null)
                 throw Error.ArgumentNull(nameof(source));
@@ -51,15 +51,15 @@ public static ValueTask<TSource> FirstOrDefaultAsync<TSource>(this IAsyncEnumera
 
             return Core(source, predicate, cancellationToken);
 
-            static async ValueTask<TSource> Core(IAsyncEnumerable<TSource> source, Func<TSource, bool> predicate, CancellationToken cancellationToken)
+            static async ValueTask<TSource?> Core(IAsyncEnumerable<TSource> source, Func<TSource, bool> predicate, CancellationToken cancellationToken)
             {
                 var first = await TryGetFirst(source, predicate, cancellationToken).ConfigureAwait(false);
 
-                return first.HasValue ? first.Value : default!;
+                return first.HasValue ? first.Value : default;
             }
         }
 
-        internal static ValueTask<TSource> FirstOrDefaultAwaitAsyncCore<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, ValueTask<bool>> predicate, CancellationToken cancellationToken = default)
+        internal 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));
@@ -68,16 +68,16 @@ internal static ValueTask<TSource> FirstOrDefaultAwaitAsyncCore<TSource>(this IA
 
             return Core(source, predicate, cancellationToken);
 
-            static async ValueTask<TSource> Core(IAsyncEnumerable<TSource> source, Func<TSource, ValueTask<bool>> predicate, CancellationToken cancellationToken)
+            static async ValueTask<TSource?> Core(IAsyncEnumerable<TSource> source, Func<TSource, ValueTask<bool>> predicate, CancellationToken cancellationToken)
             {
                 var first = await TryGetFirst(source, predicate, cancellationToken).ConfigureAwait(false);
 
-                return first.HasValue ? first.Value : default!;
+                return first.HasValue ? first.Value : default;
             }
         }
 
 #if !NO_DEEP_CANCELLATION
-        internal static ValueTask<TSource> FirstOrDefaultAwaitWithCancellationAsyncCore<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, CancellationToken, ValueTask<bool>> predicate, CancellationToken cancellationToken = default)
+        internal 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));
@@ -86,11 +86,11 @@ internal static ValueTask<TSource> FirstOrDefaultAwaitWithCancellationAsyncCore<
 
             return Core(source, predicate, cancellationToken);
 
-            static async ValueTask<TSource> Core(IAsyncEnumerable<TSource> source, Func<TSource, CancellationToken, ValueTask<bool>> predicate, CancellationToken cancellationToken)
+            static async ValueTask<TSource?> Core(IAsyncEnumerable<TSource> source, Func<TSource, CancellationToken, ValueTask<bool>> predicate, CancellationToken cancellationToken)
             {
                 var first = await TryGetFirst(source, predicate, cancellationToken).ConfigureAwait(false);
 
-                return first.HasValue ? first.Value : default!;
+                return first.HasValue ? first.Value : default;
             }
         }
 #endif

diff --git a/Ix.NET/Source/System.Linq.Async/System/Linq/Operators/LastOrDefault.cs b/Ix.NET/Source/System.Linq.Async/System/Linq/Operators/LastOrDefault.cs
@@ -18,18 +18,18 @@ public static partial class AsyncEnumerable
         /// <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, or a default value if no such element exists.</returns>
         /// <exception cref="ArgumentNullException"><paramref name="source"/> is null.</exception>
-        public static ValueTask<TSource> LastOrDefaultAsync<TSource>(this IAsyncEnumerable<TSource> source, CancellationToken cancellationToken = default)
+        public static ValueTask<TSource?> LastOrDefaultAsync<TSource>(this IAsyncEnumerable<TSource> source, CancellationToken cancellationToken = default)
         {
             if (source == null)
                 throw Error.ArgumentNull(nameof(source));
 
             return Core(source, cancellationToken);
 
-            static async ValueTask<TSource> Core(IAsyncEnumerable<TSource> source, CancellationToken cancellationToken)
+            static async ValueTask<TSource?> Core(IAsyncEnumerable<TSource> source, CancellationToken cancellationToken)
             {
                 var last = await TryGetLast(source, cancellationToken).ConfigureAwait(false);
 
-                return last.HasValue ? last.Value : default!;
+                return last.HasValue ? last.Value : default;
             }
         }
 
@@ -42,7 +42,7 @@ static async ValueTask<TSource> Core(IAsyncEnumerable<TSource> source, Cancellat
         /// <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, or a default value if no such element exists.</returns>
         /// <exception cref="ArgumentNullException"><paramref name="source"/> or <paramref name="predicate"/> is null.</exception>
-        public static ValueTask<TSource> LastOrDefaultAsync<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, bool> predicate, CancellationToken cancellationToken = default)
+        public static ValueTask<TSource?> LastOrDefaultAsync<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, bool> predicate, CancellationToken cancellationToken = default)
         {
             if (source == null)
                 throw Error.ArgumentNull(nameof(source));
@@ -51,15 +51,15 @@ public static ValueTask<TSource> LastOrDefaultAsync<TSource>(this IAsyncEnumerab
 
             return Core(source, predicate, cancellationToken);
 
-            static async ValueTask<TSource> Core(IAsyncEnumerable<TSource> source, Func<TSource, bool> predicate, CancellationToken cancellationToken)
+            static async ValueTask<TSource?> Core(IAsyncEnumerable<TSource> source, Func<TSource, bool> predicate, CancellationToken cancellationToken)
             {
                 var last = await TryGetLast(source, predicate, cancellationToken).ConfigureAwait(false);
 
-                return last.HasValue ? last.Value : default!;
+                return last.HasValue ? last.Value : default;
             }
         }
 
-        internal static ValueTask<TSource> LastOrDefaultAwaitAsyncCore<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, ValueTask<bool>> predicate, CancellationToken cancellationToken = default)
+        internal static ValueTask<TSource?> LastOrDefaultAwaitAsyncCore<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, ValueTask<bool>> predicate, CancellationToken cancellationToken = default)
         {
             if (source == null)
                 throw Error.ArgumentNull(nameof(source));
@@ -68,16 +68,16 @@ internal static ValueTask<TSource> LastOrDefaultAwaitAsyncCore<TSource>(this IAs
 
             return Core(source, predicate, cancellationToken);
 
-            static async ValueTask<TSource> Core(IAsyncEnumerable<TSource> source, Func<TSource, ValueTask<bool>> predicate, CancellationToken cancellationToken)
+            static async ValueTask<TSource?> Core(IAsyncEnumerable<TSource> source, Func<TSource, ValueTask<bool>> predicate, CancellationToken cancellationToken)
             {
                 var last = await TryGetLast(source, predicate, cancellationToken).ConfigureAwait(false);
 
-                return last.HasValue ? last.Value : default!;
+                return last.HasValue ? last.Value : default;
             }
         }
 
 #if !NO_DEEP_CANCELLATION
-        internal static ValueTask<TSource> LastOrDefaultAwaitWithCancellationAsyncCore<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, CancellationToken, ValueTask<bool>> predicate, CancellationToken cancellationToken = default)
+        internal static ValueTask<TSource?> LastOrDefaultAwaitWithCancellationAsyncCore<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, CancellationToken, ValueTask<bool>> predicate, CancellationToken cancellationToken = default)
         {
             if (source == null)
                 throw Error.ArgumentNull(nameof(source));
@@ -86,11 +86,11 @@ internal static ValueTask<TSource> LastOrDefaultAwaitWithCancellationAsyncCore<T
 
             return Core(source, predicate, cancellationToken);
 
-            static async ValueTask<TSource> Core(IAsyncEnumerable<TSource> source, Func<TSource, CancellationToken, ValueTask<bool>> predicate, CancellationToken cancellationToken)
+            static async ValueTask<TSource?> Core(IAsyncEnumerable<TSource> source, Func<TSource, CancellationToken, ValueTask<bool>> predicate, CancellationToken cancellationToken)
             {
                 var last = await TryGetLast(source, predicate, cancellationToken).ConfigureAwait(false);
 
-                return last.HasValue ? last.Value : default!;
+                return last.HasValue ? last.Value : default;
             }
         }
 #endif

diff --git a/Ix.NET/Source/System.Linq.Async/System/Linq/Operators/SingleOrDefault.cs b/Ix.NET/Source/System.Linq.Async/System/Linq/Operators/SingleOrDefault.cs
@@ -19,20 +19,20 @@ public static partial class AsyncEnumerable
         /// <returns>Sequence containing the single element in the async-enumerable sequence, or a default value if no such element exists.</returns>
         /// <exception cref="ArgumentNullException"><paramref name="source"/> is null.</exception>
         /// <exception cref="InvalidOperationException">(Asynchronous) The source sequence contains more than one element.</exception>
-        public static ValueTask<TSource> SingleOrDefaultAsync<TSource>(this IAsyncEnumerable<TSource> source, CancellationToken cancellationToken = default)
+        public static ValueTask<TSource?> SingleOrDefaultAsync<TSource>(this IAsyncEnumerable<TSource> source, CancellationToken cancellationToken = default)
         {
             if (source == null)
                 throw Error.ArgumentNull(nameof(source));
 
             return Core(source, cancellationToken);
 
-            static async ValueTask<TSource> Core(IAsyncEnumerable<TSource> source, CancellationToken cancellationToken)
+            static async ValueTask<TSource?> Core(IAsyncEnumerable<TSource> source, CancellationToken cancellationToken)
             {
                 if (source is IList<TSource> list)
                 {
                     return list.Count switch
                     {
-                        0 => default!,
+                        0 => default,
                         1 => list[0],
                         _ => throw Error.MoreThanOneElement(),
                     };
@@ -42,7 +42,7 @@ static async ValueTask<TSource> Core(IAsyncEnumerable<TSource> source, Cancellat
                 {
                     if (!await e.MoveNextAsync())
                     {
-                        return default!;
+                        return default;
                     }
 
                     var result = e.Current;
@@ -67,7 +67,7 @@ static async ValueTask<TSource> Core(IAsyncEnumerable<TSource> source, Cancellat
         /// <returns>Sequence containing the single element in the async-enumerable sequence that satisfies the condition in the predicate, or a default value if no such element exists.</returns>
         /// <exception cref="ArgumentNullException"><paramref name="source"/> or <paramref name="predicate"/> is null.</exception>
         /// <exception cref="InvalidOperationException">(Asynchronous) The sequence contains more than one element that satisfies the condition in the predicate.</exception>
-        public static ValueTask<TSource> SingleOrDefaultAsync<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, bool> predicate, CancellationToken cancellationToken = default)
+        public static ValueTask<TSource?> SingleOrDefaultAsync<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, bool> predicate, CancellationToken cancellationToken = default)
         {
             if (source == null)
                 throw Error.ArgumentNull(nameof(source));
@@ -76,7 +76,7 @@ public static ValueTask<TSource> SingleOrDefaultAsync<TSource>(this IAsyncEnumer
 
             return Core(source, predicate, cancellationToken);
 
-            static async ValueTask<TSource> Core(IAsyncEnumerable<TSource> source, Func<TSource, bool> predicate, CancellationToken cancellationToken)
+            static async ValueTask<TSource?> Core(IAsyncEnumerable<TSource> source, Func<TSource, bool> predicate, CancellationToken cancellationToken)
             {
                 await using (var e = source.GetConfiguredAsyncEnumerator(cancellationToken, false))
                 {
@@ -99,11 +99,11 @@ static async ValueTask<TSource> Core(IAsyncEnumerable<TSource> source, Func<TSou
                     }
                 }
 
-                return default!;
+                return default;
             }
         }
 
-        internal static ValueTask<TSource> SingleOrDefaultAwaitAsyncCore<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, ValueTask<bool>> predicate, CancellationToken cancellationToken = default)
+        internal static ValueTask<TSource?> SingleOrDefaultAwaitAsyncCore<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, ValueTask<bool>> predicate, CancellationToken cancellationToken = default)
         {
             if (source == null)
                 throw Error.ArgumentNull(nameof(source));
@@ -112,7 +112,7 @@ internal static ValueTask<TSource> SingleOrDefaultAwaitAsyncCore<TSource>(this I
 
             return Core(source, predicate, cancellationToken);
 
-            static async ValueTask<TSource> Core(IAsyncEnumerable<TSource> source, Func<TSource, ValueTask<bool>> predicate, CancellationToken cancellationToken)
+            static async ValueTask<TSource?> Core(IAsyncEnumerable<TSource> source, Func<TSource, ValueTask<bool>> predicate, CancellationToken cancellationToken)
             {
                 await using (var e = source.GetConfiguredAsyncEnumerator(cancellationToken, false))
                 {
@@ -135,12 +135,12 @@ static async ValueTask<TSource> Core(IAsyncEnumerable<TSource> source, Func<TSou
                     }
                 }
 
-                return default!;
+                return default;
             }
         }
 
 #if !NO_DEEP_CANCELLATION
-        internal static ValueTask<TSource> SingleOrDefaultAwaitWithCancellationAsyncCore<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, CancellationToken, ValueTask<bool>> predicate, CancellationToken cancellationToken = default)
+        internal static ValueTask<TSource?> SingleOrDefaultAwaitWithCancellationAsyncCore<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, CancellationToken, ValueTask<bool>> predicate, CancellationToken cancellationToken = default)
         {
             if (source == null)
                 throw Error.ArgumentNull(nameof(source));
@@ -149,7 +149,7 @@ internal static ValueTask<TSource> SingleOrDefaultAwaitWithCancellationAsyncCore
 
             return Core(source, predicate, cancellationToken);
 
-            static async ValueTask<TSource> Core(IAsyncEnumerable<TSource> source, Func<TSource, CancellationToken, ValueTask<bool>> predicate, CancellationToken cancellationToken)
+            static async ValueTask<TSource?> Core(IAsyncEnumerable<TSource> source, Func<TSource, CancellationToken, ValueTask<bool>> predicate, CancellationToken cancellationToken)
             {
                 await using (var e = source.GetConfiguredAsyncEnumerator(cancellationToken, false))
                 {
@@ -172,7 +172,7 @@ static async ValueTask<TSource> Core(IAsyncEnumerable<TSource> source, Func<TSou
                     }
                 }
 
-                return default!;
+                return default;
             }
         }
 #endif