NullReferenceException - When git is blocked access to a created tree object

[aroden-salesforce]

When using git-tfs to import a tree antivirus (or other bloatware) blocks access to a freshly created object tree file.

Expected behavior

• Libgit2sharp fails gracefully with error message

Bug behavior

• Libgit2sharp fails with NullReferenceException

Failure stacktrace from git-tfs usage
 System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.NullReferenceException: Object reference not set to an instance of an object.
   at LibGit2Sharp.TreeEntryDefinition.From(Tree tree) in d:\g\git-tfs\lib\libgit2sharp\LibGit2Sharp\TreeEntryDefinition.cs:line 91
   at LibGit2Sharp.TreeDefinition.WrapAllTreeDefinitions(Repository repository) in d:\g\git-tfs\lib\libgit2sharp\LibGit2Sharp\TreeDefinition.cs:line 322
   at LibGit2Sharp.TreeDefinition.Build(Repository repository) in d:\g\git-tfs\lib\libgit2sharp\LibGit2Sharp\TreeDefinition.cs:line 284   at LibGit2Sharp.TreeDefinition.WrapAllTreeDefinitions(Repository repository) in d:\g\git-tfs\lib\libgit2sharp\LibGit2Sharp\TreeDefinition.cs:line 321
   at LibGit2Sharp.TreeDefinition.Build(Repository repository) in d:\g\git-tfs\lib\libgit2sharp\LibGit2Sharp\TreeDefinition.cs:line 284
   at LibGit2Sharp.TreeDefinition.WrapAllTreeDefinitions(Repository repository) in d:\g\git-tfs\lib\libgit2sharp\LibGit2Sharp\TreeDefinition.cs:line 321
   at LibGit2Sharp.TreeDefinition.Build(Repository repository) in d:\g\git-tfs\lib\libgit2sharp\LibGit2Sharp\TreeDefinition.cs:line 284
   at LibGit2Sharp.TreeDefinition.WrapAllTreeDefinitions(Repository repository) in d:\g\git-tfs\lib\libgit2sharp\LibGit2Sharp\TreeDefinition.cs:line 321
   at LibGit2Sharp.TreeDefinition.Build(Repository repository) in d:\g\git-tfs\lib\libgit2sharp\LibGit2Sharp\TreeDefinition.cs:line 284
   at LibGit2Sharp.ObjectDatabase.CreateTree(TreeDefinition treeDefinition) in d:\g\git-tfs\lib\libgit2sharp\LibGit2Sharp\ObjectDatabase.cs:line 259
   at Sep.Git.Tfs.Core.GitTreeBuilder.GetTree() in d:\g\git-tfs\GitTfs\Core\GitTreeBuilder.cs:line 34
   at Sep.Git.Tfs.Core.GitTfsRemote.<>c__DisplayClass1e.<Apply>b__1d(ITfsWorkspace workspace) in d:\g\git-tfs\GitTfs\Core\GitTfsRemote.cs:line 706
   at Sep.Git.Tfs.VsCommon.TfsHelperBase.WithWorkspace(String localDirectory, IGitTfsRemote remote, TfsChangesetInfo versionToFetch, Action`1 action)
   at Sep.Git.Tfs.Core.GitTfsRemote.WithWorkspace(TfsChangesetInfo parentChangeset, Action`1 action) in d:\g\git-tfs\GitTfs\Core\GitTfsRemote.cs:line 837
   at Sep.Git.Tfs.Core.GitTfsRemote.Apply(String parent, ITfsChangeset changeset, IDictionary`2 entries, Action`1 ignorableErrorHandler) ind:\g\git-tfs\GitTfs\Core\GitTfsRemote.cs:line 702
   at Sep.Git.Tfs.Core.GitTfsRemote.Apply(String parent, ITfsChangeset changeset, IDictionary`2 entries) in d:\g\git-tfs\GitTfs\Core\GitTfsRemote.cs:line 691
   at Sep.Git.Tfs.Core.GitTfsRemote.FetchWithMerge(Int64 mergeChangesetId, Boolean stopOnFailMergeCommit, Int32 lastChangesetIdToFetch, String[] parentCommitsHashes) in d:\g\git-tfs\GitTfs\Core\GitTfsRemote.cs:line 347
   at Sep.Git.Tfs.Core.GitTfsRemote.FindRemoteAndFetch(Int32 parentChangesetId, Boolean stopOnFailMergeCommit, Boolean mergeChangeset, String& omittedParentBranch) in d:\g\git-tfs\GitTfs\Core\GitTfsRemote.cs:line 534
   at Sep.Git.Tfs.Core.GitTfsRemote.FindMergedRemoteAndFetch(Int32 parentChangesetId, Boolean stopOnFailMergeCommit, String& omittedParentBranch) in d:\g\git-tfs\GitTfs\Core\GitTfsRemote.cs:line 524
   at Sep.Git.Tfs.Core.GitTfsRemote.ProcessMergeChangeset(ITfsChangeset changeset, Boolean stopOnFailMergeCommit, String& parentCommit) in d:\g\git-tfs\GitTfs\Core\GitTfsRemote.cs:line 398
   at Sep.Git.Tfs.Core.GitTfsRemote.FetchWithMerge(Int64 mergeChangesetId, Boolean stopOnFailMergeCommit, Int32 lastChangesetIdToFetch, String[] parentCommitsHashes) in d:\g\git-tfs\GitTfs\Core\GitTfsRemote.cs:line 342
   at Sep.Git.Tfs.Core.GitTfsRemote.FetchWithMerge(Int64 mergeChangesetId, Boolean stopOnFailMergeCommit, String[] parentCommitsHashes) in d:\g\git-tfs\GitTfs\Core\GitTfsRemote.cs:line 314
   at Sep.Git.Tfs.Core.GitTfsRemote.Fetch(Boolean stopOnFailMergeCommit) in d:\g\git-tfs\GitTfs\Core\GitTfsRemote.cs:line 309
   at Sep.Git.Tfs.Commands.Fetch.DoFetch(IGitTfsRemote remote, Boolean stopOnFailMergeCommit) in d:\g\git-tfs\GitTfs\Commands\Fetch.cs:line184
   at Sep.Git.Tfs.Commands.Fetch.FetchRemote(Boolean stopOnFailMergeCommit, IGitTfsRemote remote) in d:\g\git-tfs\GitTfs\Commands\Fetch.cs:line 113
   at Sep.Git.Tfs.Commands.Fetch.Run(Boolean stopOnFailMergeCommit, String[] args) in d:\g\git-tfs\GitTfs\Commands\Fetch.cs:line 105
   at Sep.Git.Tfs.Commands.Fetch.Run(String[] args) in d:\g\git-tfs\GitTfs\Commands\Fetch.cs:line 95
   at Sep.Git.Tfs.Commands.Pull.Run(String remoteId) in d:\g\git-tfs\GitTfs\Commands\Pull.cs:line 44
   at Sep.Git.Tfs.Commands.Pull.Run() in d:\g\git-tfs\GitTfs\Commands\Pull.cs:line 39
   --- End of inner exception stack trace ---
   at System.RuntimeMethodHandle.InvokeMethod(Object target, Object[] arguments, Signature sig, Boolean constructor)
   at System.Reflection.RuntimeMethodInfo.UnsafeInvokeInternal(Object obj, Object[] parameters, Object[] arguments)
   at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo cultur
e)
   at System.Reflection.MethodBase.Invoke(Object obj, Object[] parameters)
   at Sep.Git.Tfs.Util.GitTfsCommandRunner.Run(GitTfsCommand command, IList`1 args) in d:\g\git-tfs\GitTfs\Util\GitTfsCommandRunner.cs:line38
   at Sep.Git.Tfs.GitTfs.Main(GitTfsCommand command, IList`1 unparsedArgs) in d:\g\git-tfs\GitTfs\GitTfs.cs:line 69
   at Sep.Git.Tfs.GitTfs.Run(IList`1 args) in d:\g\git-tfs\GitTfs\GitTfs.cs:line 50
   at Sep.Git.Tfs.Program.MainCore(String[] args) in d:\g\git-tfs\GitTfs\Program.cs:line 34
   at Sep.Git.Tfs.Program.Main(String[] args) in d:\g\git-tfs\GitTfs\Program.cs:line 22
Object reference not set to an instance of an object.

[aroden-salesforce]

uploading a pull request for this

[aroden-salesforce]

Graceful failure merged #1029