more nullable work

Author: nkolev92

src/NuGet.Core/NuGet.Common/MsBuildStringUtility.cs

@@ -91,7 +91,7 @@ public static bool IsTrueOrEmpty(string? value)
         /// </summary>
         /// <param name="s">A comma or semicolon delimited list of NuGet log codes.</param>
         /// <returns>An <see cref="IList{T}" /> containing the <see cref="NuGetLogCode" /> values that were successfully parsed from the specified string.</returns>
-        public static ImmutableArray<NuGetLogCode> GetNuGetLogCodes(string s)
+        public static ImmutableArray<NuGetLogCode> GetNuGetLogCodes(string? s)
         {
             // The Split() method already checks for an empty string and returns Array.Empty<string>().
             string[] split = MSBuildStringUtility.Split(s, ';', ',');

src/NuGet.Core/NuGet.Common/PublicAPI.Shipped.txt

@@ -576,7 +576,7 @@ static NuGet.Common.LoggingExtensions.GetName(this NuGet.Common.NuGetLogCode cod
 static NuGet.Common.LoggingExtensions.TryGetName(this NuGet.Common.NuGetLogCode code, out string? codeString) -> bool
 static NuGet.Common.MSBuildStringUtility.Convert(string? value) -> string?
 static NuGet.Common.MSBuildStringUtility.GetBooleanOrNull(string? value) -> bool?
-static NuGet.Common.MSBuildStringUtility.GetNuGetLogCodes(string! s) -> System.Collections.Immutable.ImmutableArray<NuGet.Common.NuGetLogCode>
+static NuGet.Common.MSBuildStringUtility.GetNuGetLogCodes(string? s) -> System.Collections.Immutable.ImmutableArray<NuGet.Common.NuGetLogCode>
 static NuGet.Common.MSBuildStringUtility.IsTrue(string? value) -> bool
 static NuGet.Common.MSBuildStringUtility.IsTrueOrEmpty(string? value) -> bool
 static NuGet.Common.MSBuildStringUtility.Split(string? s) -> string![]!

src/NuGet.Core/NuGet.ProjectModel/CentralTransitiveDependencyGroup.cs

@@ -1,8 +1,6 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
-#nullable disable
-
 using System;
 using System.Collections.Generic;
 using NuGet.Frameworks;
@@ -32,7 +30,7 @@ public CentralTransitiveDependencyGroup(NuGetFramework framework, IEnumerable<Li
 
         public IEnumerable<LibraryDependency> TransitiveDependencies { get; }
 
-        public bool Equals(CentralTransitiveDependencyGroup other)
+        public bool Equals(CentralTransitiveDependencyGroup? other)
         {
             if (other == null)
             {
@@ -52,7 +50,7 @@ public bool Equals(CentralTransitiveDependencyGroup other)
             return false;
         }
 
-        public override bool Equals(object obj)
+        public override bool Equals(object? obj)
         {
             return Equals(obj as CentralTransitiveDependencyGroup);
         }

src/NuGet.Core/NuGet.ProjectModel/IExternalProjectReferenceProvider.cs

@@ -1,12 +1,12 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
-#nullable disable
-
+using System;
 using System.Collections.Generic;
 
 namespace NuGet.ProjectModel
 {
+    [Obsolete("This API is unused and will be removed in a future release.")]
     /// <summary>
     /// Provides external project reference closures.
     /// </summary>

src/NuGet.Core/NuGet.ProjectModel/ProjectFileDependencyGroup.cs

@@ -1,8 +1,6 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
-#nullable disable
-
 using System;
 using System.Collections.Generic;
 using NuGet.Shared;
@@ -13,15 +11,15 @@ public class ProjectFileDependencyGroup : IEquatable<ProjectFileDependencyGroup>
     {
         public ProjectFileDependencyGroup(string frameworkName, IEnumerable<string> dependencies)
         {
-            FrameworkName = frameworkName;
-            Dependencies = dependencies;
+            FrameworkName = frameworkName ?? throw new ArgumentNullException(nameof(frameworkName));
+            Dependencies = dependencies ?? throw new ArgumentNullException(nameof(dependencies));
         }
 
         public string FrameworkName { get; }
 
         public IEnumerable<string> Dependencies { get; }
 
-        public bool Equals(ProjectFileDependencyGroup other)
+        public bool Equals(ProjectFileDependencyGroup? other)
         {
             if (other == null)
             {
@@ -46,7 +44,7 @@ public bool Equals(ProjectFileDependencyGroup other)
             return false;
         }
 
-        public override bool Equals(object obj)
+        public override bool Equals(object? obj)
         {
             return Equals(obj as ProjectFileDependencyGroup);
         }

src/NuGet.Core/NuGet.ProjectModel/ProjectRestoreMetadataFile.cs

@@ -1,8 +1,6 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
-#nullable disable
-
 using System;
 using NuGet.Shared;
 
@@ -38,7 +36,7 @@ public ProjectRestoreMetadataFile(string packagePath, string absolutePath)
             AbsolutePath = absolutePath;
         }
 
-        public bool Equals(ProjectRestoreMetadataFile other)
+        public bool Equals(ProjectRestoreMetadataFile? other)
         {
             if (ReferenceEquals(this, other))
             {
@@ -54,7 +52,7 @@ public bool Equals(ProjectRestoreMetadataFile other)
                 && StringComparer.Ordinal.Equals(AbsolutePath, other.AbsolutePath);
         }
 
-        public override bool Equals(object obj)
+        public override bool Equals(object? obj)
         {
             return Equals(obj as ProjectRestoreMetadataFile);
         }
@@ -74,9 +72,9 @@ public override string ToString()
             return PackagePath;
         }
 
-        public int CompareTo(ProjectRestoreMetadataFile other)
+        public int CompareTo(ProjectRestoreMetadataFile? other)
         {
-            return StringComparer.Ordinal.Compare(PackagePath, other.PackagePath);
+            return StringComparer.Ordinal.Compare(PackagePath, other?.PackagePath);
         }
 
         public ProjectRestoreMetadataFile Clone()

src/NuGet.Core/NuGet.ProjectModel/ProjectRestoreSettings.cs

@@ -1,8 +1,6 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
-#nullable disable
-
 using NuGet.Shared;
 using NuGet.Versioning;
 
@@ -23,7 +21,7 @@ public class ProjectRestoreSettings
         /// Indicates the .NET SDK Version if any.
         /// In combination with SdkAnalysisLevel, it allows us to determine whether the analysis level is the default one or manually specified.
         /// </summary>
-        public NuGetVersion SdkVersion { get; set; }
+        public NuGetVersion? SdkVersion { get; set; }
 
         public ProjectRestoreSettings Clone()
         {
@@ -33,12 +31,12 @@ public ProjectRestoreSettings Clone()
             return clonedObject;
         }
 
-        public override bool Equals(object obj)
+        public override bool Equals(object? obj)
         {
             return Equals(obj as ProjectRestoreSettings);
         }
 
-        public bool Equals(ProjectRestoreSettings other)
+        public bool Equals(ProjectRestoreSettings? other)
         {
             if (other == null)
             {