nullable cleanup for LibGit2Sharp implementation

arturcic · arturcic · commit 01c8940d3993 · 2021-01-19T17:12:49.000+02:00
diff --git a/src/GitTools.Testing/GitTestExtensions.cs b/src/GitTools.Testing/GitTestExtensions.cs
@@ -30,7 +30,7 @@ public static void MergeNoFF(this IRepository repository, string branch, Signatu
         public static Commit[] MakeCommits(this IRepository repository, int numCommitsToMake)
         {
             return Enumerable.Range(1, numCommitsToMake)
-                             .Select(x => repository.MakeACommit())
+                             .Select(_ => repository.MakeACommit())
                              .ToArray();
         }
 
diff --git a/src/GitVersion.LibGit2Sharp/Git/Branch.cs b/src/GitVersion.LibGit2Sharp/Git/Branch.cs
@@ -11,13 +11,10 @@ internal class Branch : IBranch
 
         private readonly LibGit2Sharp.Branch innerBranch;
 
-        internal Branch(LibGit2Sharp.Branch branch)
-        {
-            innerBranch = branch;
-        }
+        internal Branch(LibGit2Sharp.Branch branch) => innerBranch = branch;
 
         public int CompareTo(IBranch other) => comparerHelper.Compare(this, other);
-        public override bool Equals(object obj) => Equals(obj as IBranch);
+        public override bool Equals(object obj) => Equals((obj as IBranch)!);
         public bool Equals(IBranch other) => equalityHelper.Equals(this, other);
         public override int GetHashCode() => equalityHelper.GetHashCode(this);
         public static implicit operator LibGit2Sharp.Branch(Branch d) => d.innerBranch;
@@ -35,7 +32,7 @@ internal Branch(LibGit2Sharp.Branch branch)
                 ? FriendlyName.Substring("origin/".Length)
                 : FriendlyName;
 
-        public virtual ICommit Tip
+        public virtual ICommit? Tip
         {
             get
             {
@@ -44,7 +41,7 @@ public virtual ICommit Tip
             }
         }
 
-        public virtual ICommitCollection Commits
+        public virtual ICommitCollection? Commits
         {
             get
             {
diff --git a/src/GitVersion.LibGit2Sharp/Git/BranchCollection.cs b/src/GitVersion.LibGit2Sharp/Git/BranchCollection.cs
@@ -14,11 +14,11 @@ public virtual IEnumerator<IBranch> GetEnumerator()
             return innerCollection.Select(branch => new Branch(branch)).GetEnumerator();
         }
         IEnumerator IEnumerable.GetEnumerator() => GetEnumerator();
-        public virtual IBranch this[string friendlyName]
+        public virtual IBranch? this[string friendlyName]
         {
             get
             {
-                var branch = innerCollection?[friendlyName];
+                var branch = innerCollection[friendlyName];
                 return branch is null ? null : new Branch(branch);
             }
         }
diff --git a/src/GitVersion.LibGit2Sharp/Git/Commit.cs b/src/GitVersion.LibGit2Sharp/Git/Commit.cs
@@ -11,19 +11,16 @@ internal class Commit : ICommit
 
         private readonly LibGit2Sharp.Commit innerObjectId;
 
-        internal Commit(LibGit2Sharp.Commit objectId)
-        {
-            innerObjectId = objectId;
-        }
+        internal Commit(LibGit2Sharp.Commit objectId) => innerObjectId = objectId;
 
         public int CompareTo(ICommit other) => comparerHelper.Compare(this, other);
-        public override bool Equals(object obj) => Equals(obj as ICommit);
+        public override bool Equals(object obj) => Equals((obj as ICommit)!);
         public bool Equals(ICommit other) => equalityHelper.Equals(this, other);
         public override int GetHashCode() => equalityHelper.GetHashCode(this);
 
         public static implicit operator LibGit2Sharp.Commit(Commit d) => d.innerObjectId;
 
-        public virtual IEnumerable<ICommit> Parents
+        public virtual IEnumerable<ICommit?> Parents
         {
             get
             {
@@ -36,7 +33,7 @@ public virtual IEnumerable<ICommit> Parents
 
         public virtual string Sha => innerObjectId.Sha;
 
-        public virtual IObjectId Id
+        public virtual IObjectId? Id
         {
             get
             {
diff --git a/src/GitVersion.LibGit2Sharp/Git/CommitCollection.cs b/src/GitVersion.LibGit2Sharp/Git/CommitCollection.cs
@@ -21,7 +21,7 @@ public virtual IEnumerator<ICommit> GetEnumerator()
         public IEnumerable<ICommit> GetCommitsPriorTo(DateTimeOffset olderThan) => this.SkipWhile(c => c.CommitterWhen > olderThan);
         public virtual ICommitCollection QueryBy(CommitFilter commitFilter)
         {
-            static object GetReacheableFrom(object item)
+            static object? GetReacheableFrom(object item)
             {
                 return item switch
                 {
diff --git a/src/GitVersion.LibGit2Sharp/Git/GitRepository.cs b/src/GitVersion.LibGit2Sharp/Git/GitRepository.cs
@@ -25,6 +25,7 @@ internal GitRepository(ILog log, string gitRootDirectory)
 
         internal GitRepository(IRepository repository)
         {
+            log = new NullLog();
             repositoryLazy = new Lazy<IRepository>(() => repository);
         }
 
@@ -133,7 +134,7 @@ public void CreateBranchForPullRequestBranch(AuthenticationInfo auth)
 
             log.Info($"Remote Refs:{System.Environment.NewLine}" + string.Join(System.Environment.NewLine, remoteTips.Select(r => r.CanonicalName)));
 
-            var headTipSha = Head.Tip.Sha;
+            var headTipSha = Head.Tip?.Sha;
 
             var refs = remoteTips.Where(r => r.TargetIdentifier == headTipSha).ToList();
 
@@ -242,11 +243,11 @@ private static CloneOptions GetCloneOptions(AuthenticationInfo auth)
                 CredentialsProvider = GetCredentialsProvider(auth)
             };
         }
-        private static CredentialsHandler GetCredentialsProvider(AuthenticationInfo auth)
+        private static CredentialsHandler? GetCredentialsProvider(AuthenticationInfo auth)
         {
             if (!string.IsNullOrWhiteSpace(auth.Username))
             {
-                return (url, user, types) => new UsernamePasswordCredentials
+                return (_, _, _) => new UsernamePasswordCredentials
                 {
                     Username = auth.Username,
                     Password = auth.Password ?? string.Empty
@@ -289,7 +290,7 @@ public IEnumerable<ICommit> GetCommitsReacheableFromHead(ICommit headCommit)
 
             return commitCollection.ToList();
         }
-        public ICommit GetForwardMerge(ICommit commitToFindCommonBase, ICommit findMergeBase)
+        public ICommit? GetForwardMerge(ICommit commitToFindCommonBase, ICommit findMergeBase)
         {
             var filter = new CommitFilter
             {
@@ -302,7 +303,7 @@ public ICommit GetForwardMerge(ICommit commitToFindCommonBase, ICommit findMerge
                 .FirstOrDefault(c => c.Parents.Contains(findMergeBase));
             return forwardMerge;
         }
-        public IEnumerable<ICommit> GetMergeBaseCommits(ICommit mergeCommit, ICommit mergedHead, ICommit findMergeBase)
+        public IEnumerable<ICommit> GetMergeBaseCommits(ICommit? mergeCommit, ICommit mergedHead, ICommit findMergeBase)
         {
             var filter = new CommitFilter
             {
diff --git a/src/GitVersion.LibGit2Sharp/Git/GitRepositoryInfo.cs b/src/GitVersion.LibGit2Sharp/Git/GitRepositoryInfo.cs
@@ -11,27 +11,27 @@ internal class GitRepositoryInfo : IGitRepositoryInfo
         private readonly IOptions<GitVersionOptions> options;
         private GitVersionOptions gitVersionOptions => options.Value;
 
-        private Lazy<string> dotGitDirectory;
+        private Lazy<string?> dynamicGitRepositoryPath;
+        private Lazy<string?> dotGitDirectory;
+        private Lazy<string?> gitRootPath;
         private Lazy<string> projectRootDirectory;
-        private Lazy<string> dynamicGitRepositoryPath;
-        private Lazy<string> gitRootPath;
 
         public GitRepositoryInfo(IOptions<GitVersionOptions> options)
         {
             this.options = options ?? throw new ArgumentNullException(nameof(options));
 
-            dynamicGitRepositoryPath = new Lazy<string>(GetDynamicGitRepositoryPath);
-            dotGitDirectory = new Lazy<string>(GetDotGitDirectory);
+            dynamicGitRepositoryPath = new Lazy<string?>(GetDynamicGitRepositoryPath);
+            dotGitDirectory = new Lazy<string?>(GetDotGitDirectory);
+            gitRootPath = new Lazy<string?>(GetGitRootPath);
             projectRootDirectory = new Lazy<string>(GetProjectRootDirectory);
-            gitRootPath = new Lazy<string>(GetGitRootPath);
         }
 
-        public string DotGitDirectory => dotGitDirectory.Value;
+        public string? DynamicGitRepositoryPath => dynamicGitRepositoryPath.Value;
+        public string? DotGitDirectory => dotGitDirectory.Value;
+        public string? GitRootPath => gitRootPath.Value;
         public string ProjectRootDirectory => projectRootDirectory.Value;
-        public string DynamicGitRepositoryPath => dynamicGitRepositoryPath.Value;
-        public string GitRootPath => gitRootPath.Value;
 
-        private string GetDynamicGitRepositoryPath()
+        private string? GetDynamicGitRepositoryPath()
         {
             var repositoryInfo = gitVersionOptions.RepositoryInfo;
             if (string.IsNullOrWhiteSpace(repositoryInfo.TargetUrl)) return null;
@@ -60,7 +60,7 @@ private string GetDynamicGitRepositoryPath()
             return repositoryPath;
         }
 
-        private string GetDotGitDirectory()
+        private string? GetDotGitDirectory()
         {
             var _dotGitDirectory = !string.IsNullOrWhiteSpace(DynamicGitRepositoryPath)
                 ? DynamicGitRepositoryPath
@@ -70,7 +70,7 @@ private string GetDotGitDirectory()
             if (string.IsNullOrEmpty(_dotGitDirectory))
                 throw new DirectoryNotFoundException("Cannot find the .git directory");
 
-            return _dotGitDirectory.Contains(Path.Combine(".git", "worktrees"))
+            return _dotGitDirectory is null ? null : _dotGitDirectory.Contains(Path.Combine(".git", "worktrees"))
                 ? Directory.GetParent(Directory.GetParent(_dotGitDirectory).FullName).FullName
                 : _dotGitDirectory;
         }
@@ -90,7 +90,7 @@ private string GetProjectRootDirectory()
             return new GitRepository(new NullLog(), _dotGitDirectory).WorkingDirectory;
         }
 
-        private string GetGitRootPath()
+        private string? GetGitRootPath()
         {
             var isDynamicRepo = !string.IsNullOrWhiteSpace(DynamicGitRepositoryPath);
             var rootDirectory = isDynamicRepo ? DotGitDirectory : ProjectRootDirectory;
diff --git a/src/GitVersion.LibGit2Sharp/Git/ObjectId.cs b/src/GitVersion.LibGit2Sharp/Git/ObjectId.cs
@@ -8,17 +8,14 @@ internal class ObjectId : IObjectId
         private static readonly LambdaKeyComparer<IObjectId, string> comparerHelper = new(x => x.Sha);
 
         private readonly LibGit2Sharp.ObjectId innerObjectId;
-        internal ObjectId(LibGit2Sharp.ObjectId objectId)
-        {
-            innerObjectId = objectId;
-        }
+        internal ObjectId(LibGit2Sharp.ObjectId objectId) => innerObjectId = objectId;
 
         public ObjectId(string sha) : this(new LibGit2Sharp.ObjectId(sha))
         {
         }
 
         public int CompareTo(IObjectId other) => comparerHelper.Compare(this, other);
-        public override bool Equals(object obj) => Equals(obj as IObjectId);
+        public override bool Equals(object obj) => Equals((obj as IObjectId)!);
         public bool Equals(IObjectId other) => equalityHelper.Equals(this, other);
         public override int GetHashCode() => equalityHelper.GetHashCode(this);
         public static implicit operator LibGit2Sharp.ObjectId(ObjectId d) => d.innerObjectId;
diff --git a/src/GitVersion.LibGit2Sharp/Git/Reference.cs b/src/GitVersion.LibGit2Sharp/Git/Reference.cs
@@ -11,13 +11,10 @@ internal class Reference : IReference
         internal readonly LibGit2Sharp.Reference innerReference;
         private DirectReference directReference => innerReference.ResolveToDirectReference();
 
-        internal Reference(LibGit2Sharp.Reference reference)
-        {
-            innerReference = reference;
-        }
+        internal Reference(LibGit2Sharp.Reference reference) => innerReference = reference;
 
         public int CompareTo(IReference other) => comparerHelper.Compare(this, other);
-        public override bool Equals(object obj) => Equals(obj as IReference);
+        public override bool Equals(object obj) => Equals((obj as IReference)!);
         public bool Equals(IReference other) => equalityHelper.Equals(this, other);
         public override int GetHashCode() => equalityHelper.GetHashCode(this);
 
diff --git a/src/GitVersion.LibGit2Sharp/Git/Remote.cs b/src/GitVersion.LibGit2Sharp/Git/Remote.cs
@@ -10,13 +10,10 @@ internal class Remote : IRemote
 
         private readonly LibGit2Sharp.Remote innerRemote;
 
-        internal Remote(LibGit2Sharp.Remote remote)
-        {
-            innerRemote = remote;
-        }
+        internal Remote(LibGit2Sharp.Remote remote) => innerRemote = remote;
 
         public int CompareTo(IRemote other) => comparerHelper.Compare(this, other);
-        public override bool Equals(object obj) => Equals(obj as IRemote);
+        public override bool Equals(object obj) => Equals((obj as IRemote)!);
         public bool Equals(IRemote other) => equalityHelper.Equals(this, other);
         public override int GetHashCode() => equalityHelper.GetHashCode(this);
         public virtual string Name => innerRemote.Name;
diff --git a/src/GitVersion.LibGit2Sharp/Git/Tag.cs b/src/GitVersion.LibGit2Sharp/Git/Tag.cs
@@ -9,20 +9,17 @@ internal class Tag : ITag
         private static readonly LambdaKeyComparer<ITag, string> comparerHelper = new(x => x.CanonicalName);
 
         private readonly LibGit2Sharp.Tag innerTag;
-        internal Tag(LibGit2Sharp.Tag tag)
-        {
-            innerTag = tag;
-        }
+        internal Tag(LibGit2Sharp.Tag tag) => innerTag = tag;
 
         public int CompareTo(ITag other) => comparerHelper.Compare(this, other);
-        public override bool Equals(object obj) => Equals(obj as ITag);
+        public override bool Equals(object obj) => Equals((obj as ITag)!);
         public bool Equals(ITag other) => equalityHelper.Equals(this, other);
         public override int GetHashCode() => equalityHelper.GetHashCode(this);
         public virtual string CanonicalName => innerTag.CanonicalName;
         public virtual string TargetSha => innerTag.Target.Sha;
         public virtual string FriendlyName => innerTag.FriendlyName;
 
-        public ICommit PeeledTargetCommit()
+        public ICommit? PeeledTargetCommit()
         {
             var target = innerTag.Target;
 
diff --git a/src/GitVersion.LibGit2Sharp/GitVersion.LibGit2Sharp.csproj b/src/GitVersion.LibGit2Sharp/GitVersion.LibGit2Sharp.csproj
@@ -2,6 +2,7 @@
 
     <PropertyGroup>
         <TargetFramework>netstandard2.0</TargetFramework>
+        <Nullable>enable</Nullable>
     </PropertyGroup>
 
     <ItemGroup>
diff --git a/src/GitVersion.LibGit2Sharp/RepositoryExtensions.cs b/src/GitVersion.LibGit2Sharp/RepositoryExtensions.cs
@@ -1,4 +1,4 @@
-﻿using LibGit2Sharp;
+using LibGit2Sharp;
 using Microsoft.Extensions.Options;
 
 namespace GitVersion
diff --git a/src/GitVersionCore.Tests/Core/RepositoryExtensionsTests.cs b/src/GitVersionCore.Tests/Core/RepositoryExtensionsTests.cs
@@ -92,14 +92,14 @@ private static IRemote MockRemote(IGitRepository repository)
 
             var branches = Substitute.For<IBranchCollection>();
             branches[branch.CanonicalName].Returns(branch);
-            branches.GetEnumerator().Returns(x => ((IEnumerable<IBranch>)new[] { branch }).GetEnumerator());
+            branches.GetEnumerator().Returns(_ => ((IEnumerable<IBranch>)new[] { branch }).GetEnumerator());
 
             var reference = Substitute.For<IReference>();
             reference.CanonicalName.Returns("refs/heads/develop");
 
             var references = Substitute.For<IReferenceCollection>();
             references["develop"].Returns(reference);
-            references.GetEnumerator().Returns(x => ((IEnumerable<IReference>)new[] { reference }).GetEnumerator());
+            references.GetEnumerator().Returns(_ => ((IEnumerable<IReference>)new[] { reference }).GetEnumerator());
 
             repository.Refs.Returns(references);
             repository.Head.Returns(branch);
diff --git a/src/GitVersionCore/Helpers/ProcessHelper.cs b/src/GitVersionCore/Helpers/ProcessHelper.cs
@@ -121,7 +121,7 @@ public static int Run(Action<string> output, Action<string> errorOutput, TextRea
             using var mreOut = new ManualResetEvent(false);
             using var mreErr = new ManualResetEvent(false);
             process.EnableRaisingEvents = true;
-            process.OutputDataReceived += (o, e) =>
+            process.OutputDataReceived += (_, e) =>
             {
                 // ReSharper disable once AccessToDisposedClosure
                 if (e.Data == null)
@@ -130,7 +130,7 @@ public static int Run(Action<string> output, Action<string> errorOutput, TextRea
                     output(e.Data);
             };
             process.BeginOutputReadLine();
-            process.ErrorDataReceived += (o, e) =>
+            process.ErrorDataReceived += (_, e) =>
             {
                 // ReSharper disable once AccessToDisposedClosure
                 if (e.Data == null)
diff --git a/src/GitVersionExe/Program.cs b/src/GitVersionExe/Program.cs
@@ -29,11 +29,11 @@ internal Task RunAsync(string[] args)
 
         private IHostBuilder CreateHostBuilder(string[] args) =>
             new HostBuilder()
-                .ConfigureAppConfiguration((hostContext, configApp) =>
+                .ConfigureAppConfiguration((_, configApp) =>
                 {
                     configApp.AddCommandLine(args);
                 })
-                .ConfigureServices((hostContext, services) =>
+                .ConfigureServices((_, services) =>
                 {
                     services.AddModule(new GitVersionCoreModule());
                     services.AddModule(new GitVersionLibGit2SharpModule());

Original file line number	Diff line number	Diff line change
`@@ -30,7 +30,7 @@ public static void MergeNoFF(this IRepository repository, string branch, Signatu`
`30`	`30`	`public static Commit[] MakeCommits(this IRepository repository, int numCommitsToMake)`
`31`	`31`	`{`
`32`	`32`	`return Enumerable.Range(1, numCommitsToMake)`
`33`		`- .Select(x => repository.MakeACommit())`
	`33`	`+ .Select(_ => repository.MakeACommit())`
`34`	`34`	`.ToArray();`
`35`	`35`	`}`
`36`	`36`
Original file line number	Diff line number	Diff line change
`@@ -11,13 +11,10 @@ internal class Branch : IBranch`
`11`	`11`
`12`	`12`	`private readonly LibGit2Sharp.Branch innerBranch;`
`13`	`13`
`14`		`- internal Branch(LibGit2Sharp.Branch branch)`
`15`		`- {`
`16`		`- innerBranch = branch;`
`17`		`- }`
	`14`	`+ internal Branch(LibGit2Sharp.Branch branch) => innerBranch = branch;`
`18`	`15`
`19`	`16`	`public int CompareTo(IBranch other) => comparerHelper.Compare(this, other);`
`20`		`- public override bool Equals(object obj) => Equals(obj as IBranch);`
	`17`	`+ public override bool Equals(object obj) => Equals((obj as IBranch)!);`
`21`	`18`	`public bool Equals(IBranch other) => equalityHelper.Equals(this, other);`
`22`	`19`	`public override int GetHashCode() => equalityHelper.GetHashCode(this);`
`23`	`20`	`public static implicit operator LibGit2Sharp.Branch(Branch d) => d.innerBranch;`
`@@ -35,7 +32,7 @@ internal Branch(LibGit2Sharp.Branch branch)`
`35`	`32`	`? FriendlyName.Substring("origin/".Length)`
`36`	`33`	`: FriendlyName;`
`37`	`34`
`38`		`- public virtual ICommit Tip`
	`35`	`+ public virtual ICommit? Tip`
`39`	`36`	`{`
`40`	`37`	`get`
`41`	`38`	`{`
`@@ -44,7 +41,7 @@ public virtual ICommit Tip`
`44`	`41`	`}`
`45`	`42`	`}`
`46`	`43`
`47`		`- public virtual ICommitCollection Commits`
	`44`	`+ public virtual ICommitCollection? Commits`
`48`	`45`	`{`
`49`	`46`	`get`
`50`	`47`	`{`
Original file line number	Diff line number	Diff line change
`@@ -14,11 +14,11 @@ public virtual IEnumerator<IBranch> GetEnumerator()`
`14`	`14`	`return innerCollection.Select(branch => new Branch(branch)).GetEnumerator();`
`15`	`15`	`}`
`16`	`16`	`IEnumerator IEnumerable.GetEnumerator() => GetEnumerator();`
`17`		`- public virtual IBranch this[string friendlyName]`
	`17`	`+ public virtual IBranch? this[string friendlyName]`
`18`	`18`	`{`
`19`	`19`	`get`
`20`	`20`	`{`
`21`		`- var branch = innerCollection?[friendlyName];`
	`21`	`+ var branch = innerCollection[friendlyName];`
`22`	`22`	`return branch is null ? null : new Branch(branch);`
`23`	`23`	`}`
`24`	`24`	`}`
Original file line number	Diff line number	Diff line change
`@@ -11,19 +11,16 @@ internal class Commit : ICommit`
`11`	`11`
`12`	`12`	`private readonly LibGit2Sharp.Commit innerObjectId;`
`13`	`13`
`14`		`- internal Commit(LibGit2Sharp.Commit objectId)`
`15`		`- {`
`16`		`- innerObjectId = objectId;`
`17`		`- }`
	`14`	`+ internal Commit(LibGit2Sharp.Commit objectId) => innerObjectId = objectId;`
`18`	`15`
`19`	`16`	`public int CompareTo(ICommit other) => comparerHelper.Compare(this, other);`
`20`		`- public override bool Equals(object obj) => Equals(obj as ICommit);`
	`17`	`+ public override bool Equals(object obj) => Equals((obj as ICommit)!);`
`21`	`18`	`public bool Equals(ICommit other) => equalityHelper.Equals(this, other);`
`22`	`19`	`public override int GetHashCode() => equalityHelper.GetHashCode(this);`
`23`	`20`
`24`	`21`	`public static implicit operator LibGit2Sharp.Commit(Commit d) => d.innerObjectId;`
`25`	`22`
`26`		`- public virtual IEnumerable<ICommit> Parents`
	`23`	`+ public virtual IEnumerable<ICommit?> Parents`
`27`	`24`	`{`
`28`	`25`	`get`
`29`	`26`	`{`
`@@ -36,7 +33,7 @@ public virtual IEnumerable<ICommit> Parents`
`36`	`33`
`37`	`34`	`public virtual string Sha => innerObjectId.Sha;`
`38`	`35`
`39`		`- public virtual IObjectId Id`
	`36`	`+ public virtual IObjectId? Id`
`40`	`37`	`{`
`41`	`38`	`get`
`42`	`39`	`{`
Original file line number	Diff line number	Diff line change
`@@ -21,7 +21,7 @@ public virtual IEnumerator<ICommit> GetEnumerator()`
`21`	`21`	`public IEnumerable<ICommit> GetCommitsPriorTo(DateTimeOffset olderThan) => this.SkipWhile(c => c.CommitterWhen > olderThan);`
`22`	`22`	`public virtual ICommitCollection QueryBy(CommitFilter commitFilter)`
`23`	`23`	`{`
`24`		`- static object GetReacheableFrom(object item)`
	`24`	`+ static object? GetReacheableFrom(object item)`
`25`	`25`	`{`
`26`	`26`	`return item switch`
`27`	`27`	`{`
Original file line number	Diff line number	Diff line change
`@@ -25,6 +25,7 @@ internal GitRepository(ILog log, string gitRootDirectory)`
`25`	`25`
`26`	`26`	`internal GitRepository(IRepository repository)`
`27`	`27`	`{`
	`28`	`+ log = new NullLog();`
`28`	`29`	`repositoryLazy = new Lazy<IRepository>(() => repository);`
`29`	`30`	`}`
`30`	`31`
`@@ -133,7 +134,7 @@ public void CreateBranchForPullRequestBranch(AuthenticationInfo auth)`
`133`	`134`
`134`	`135`	`log.Info($"Remote Refs:{System.Environment.NewLine}" + string.Join(System.Environment.NewLine, remoteTips.Select(r => r.CanonicalName)));`
`135`	`136`
`136`		`- var headTipSha = Head.Tip.Sha;`
	`137`	`+ var headTipSha = Head.Tip?.Sha;`
`137`	`138`
`138`	`139`	`var refs = remoteTips.Where(r => r.TargetIdentifier == headTipSha).ToList();`
`139`	`140`
`@@ -242,11 +243,11 @@ private static CloneOptions GetCloneOptions(AuthenticationInfo auth)`
`242`	`243`	`CredentialsProvider = GetCredentialsProvider(auth)`
`243`	`244`	`};`
`244`	`245`	`}`
`245`		`- private static CredentialsHandler GetCredentialsProvider(AuthenticationInfo auth)`
	`246`	`+ private static CredentialsHandler? GetCredentialsProvider(AuthenticationInfo auth)`
`246`	`247`	`{`
`247`	`248`	`if (!string.IsNullOrWhiteSpace(auth.Username))`
`248`	`249`	`{`
`249`		`- return (url, user, types) => new UsernamePasswordCredentials`
	`250`	`+ return (_, _, _) => new UsernamePasswordCredentials`
`250`	`251`	`{`
`251`	`252`	`Username = auth.Username,`
`252`	`253`	`Password = auth.Password ?? string.Empty`
`@@ -289,7 +290,7 @@ public IEnumerable<ICommit> GetCommitsReacheableFromHead(ICommit headCommit)`
`289`	`290`
`290`	`291`	`return commitCollection.ToList();`
`291`	`292`	`}`
`292`		`- public ICommit GetForwardMerge(ICommit commitToFindCommonBase, ICommit findMergeBase)`
	`293`	`+ public ICommit? GetForwardMerge(ICommit commitToFindCommonBase, ICommit findMergeBase)`
`293`	`294`	`{`
`294`	`295`	`var filter = new CommitFilter`
`295`	`296`	`{`
`@@ -302,7 +303,7 @@ public ICommit GetForwardMerge(ICommit commitToFindCommonBase, ICommit findMerge`
`302`	`303`	`.FirstOrDefault(c => c.Parents.Contains(findMergeBase));`
`303`	`304`	`return forwardMerge;`
`304`	`305`	`}`
`305`		`- public IEnumerable<ICommit> GetMergeBaseCommits(ICommit mergeCommit, ICommit mergedHead, ICommit findMergeBase)`
	`306`	`+ public IEnumerable<ICommit> GetMergeBaseCommits(ICommit? mergeCommit, ICommit mergedHead, ICommit findMergeBase)`
`306`	`307`	`{`
`307`	`308`	`var filter = new CommitFilter`
`308`	`309`	`{`