Enable nullable annotations for M.E.L.Abstractions

src/libraries/Common/src/Extensions/Logging/NullExternalScopeProvider.cs

@@ -1,6 +1,8 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+#nullable enable
+
 using System;
 
 namespace Microsoft.Extensions.Logging
@@ -20,12 +22,12 @@ private NullExternalScopeProvider()
         public static IExternalScopeProvider Instance { get; } = new NullExternalScopeProvider();
 
         /// <inheritdoc />
-        void IExternalScopeProvider.ForEachScope<TState>(Action<object, TState> callback, TState state)
+        void IExternalScopeProvider.ForEachScope<TState>(Action<object?, TState> callback, TState state)
         {
         }
 
         /// <inheritdoc />
-        IDisposable IExternalScopeProvider.Push(object state)
+        IDisposable IExternalScopeProvider.Push(object? state)
         {
             return NullScope.Instance;
         }

src/libraries/Common/src/Extensions/TypeNameHelper/TypeNameHelper.cs

@@ -1,9 +1,12 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+#nullable enable
+
 using System;
 using System.Text;
 using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
 
 namespace Microsoft.Extensions.Internal
 {
@@ -31,7 +34,8 @@ internal static class TypeNameHelper
             { typeof(ushort), "ushort" }
         };
 
-        public static string GetTypeDisplayName(object item, bool fullName = true)
+        [return: NotNullIfNotNull("item")]
+        public static string? GetTypeDisplayName(object? item, bool fullName = true)
         {
             return item == null ? null : GetTypeDisplayName(item.GetType(), fullName);
         }
@@ -63,7 +67,7 @@ private static void ProcessType(StringBuilder builder, Type type, in DisplayName
             {
                 ProcessArrayType(builder, type, options);
             }
-            else if (_builtInTypeNames.TryGetValue(type, out string builtInName))
+            else if (_builtInTypeNames.TryGetValue(type, out string? builtInName))
             {
                 builder.Append(builtInName);
             }
@@ -76,7 +80,7 @@ private static void ProcessType(StringBuilder builder, Type type, in DisplayName
             }
             else
             {
-                string name = options.FullName ? type.FullName : type.Name;
+                string name = options.FullName ? type.FullName! : type.Name;
                 builder.Append(name);
 
                 if (options.NestedTypeDelimiter != DefaultNestedTypeDelimiter)
@@ -91,7 +95,7 @@ private static void ProcessArrayType(StringBuilder builder, Type type, in Displa
             Type innerType = type;
             while (innerType.IsArray)
             {
-                innerType = innerType.GetElementType();
+                innerType = innerType.GetElementType()!;
             }
 
             ProcessType(builder, innerType, options);
@@ -101,7 +105,7 @@ private static void ProcessArrayType(StringBuilder builder, Type type, in Displa
                 builder.Append('[');
                 builder.Append(',', type.GetArrayRank() - 1);
                 builder.Append(']');
-                type = type.GetElementType();
+                type = type.GetElementType()!;
             }
         }
 
@@ -110,14 +114,14 @@ private static void ProcessGenericType(StringBuilder builder, Type type, Type[]
             int offset = 0;
             if (type.IsNested)
             {
-                offset = type.DeclaringType.GetGenericArguments().Length;
+                offset = type.DeclaringType!.GetGenericArguments().Length;
             }
 
             if (options.FullName)
             {
                 if (type.IsNested)
                 {
-                    ProcessGenericType(builder, type.DeclaringType, genericArguments, offset, options);
+                    ProcessGenericType(builder, type.DeclaringType!, genericArguments, offset, options);
                     builder.Append(options.NestedTypeDelimiter);
                 }
                 else if (!string.IsNullOrEmpty(type.Namespace))

src/libraries/Microsoft.Extensions.DependencyInjection/src/Microsoft.Extensions.DependencyInjection.csproj

@@ -4,6 +4,7 @@
     <TargetFrameworks>$(NetCoreAppCurrent);net461;netstandard2.0;netstandard2.1</TargetFrameworks>
     <!-- Debug IL generation -->
     <ILEmitBackendSaveAssemblies>False</ILEmitBackendSaveAssemblies>
+    <Nullable>Annotations</Nullable>
   </PropertyGroup>
 
   <!-- DesignTimeBuild requires all the TargetFramework Derived Properties to not be present in the first property group. -->

src/libraries/Microsoft.Extensions.Http/src/Microsoft.Extensions.Http.csproj

@@ -3,6 +3,7 @@
   <PropertyGroup>
     <TargetFrameworks>netstandard2.0;net461</TargetFrameworks>
     <EnableDefaultItems>true</EnableDefaultItems>
+    <Nullable>Annotations</Nullable>
   </PropertyGroup>
 
   <ItemGroup>