[Bug]: null value in FieldValueMap is not handled

[sbouchexbellomie-Philips]

Version

• I confirm that I am using the latest version

Source Version

Azure DevOps Service

Target Version

Azure DevOps Server 2022

Relevant configuration

FieldMappingTool is configured with the following :

...

      "FieldMappingTool": {
        "Enabled": true,
        "FieldMaps": [
          {
            "FieldMapType": "FieldValueMap",
            "sourceField": "Microsoft.VSTS.Common.Severity",
            "targetField": "Microsoft.VSTS.Common.Severity",
            "defaultValue": null,
            "valueMapping": {
              "1 - Blocker": "1 - Blocker",
              "2 - Major": "2 - Major",
              "3 - Moderate": "3 - Moderate",
              "4 - Minor": "4 - Minor"
            },
            "ApplyTo": ["Bug"]
          }

...

Relevant log output

[17:51:56 DBG] [16.0.9] Running Field Map: FieldValueMap Microsoft.VSTS.Common.Priority Aaa.Rank
[17:51:56 ERR] [16.0.9] Field map fault
System.NullReferenceException: La référence d'objet n'est pas définie à une instance d'un objet.
   à MigrationTools.FieldMaps.AzureDevops.ObjectModel.FieldValueMap.InternalExecute(WorkItemData source, WorkItemData target) dans D:\a\azure-devops-migration-tools\azure-devops-migration-tools\src\MigrationTools.Clients.TfsObjectModel\Tools\FieldMappingTool\FieldMaps\FieldValueMap.cs:ligne 41
   à MigrationTools.FieldMaps.AzureDevops.ObjectModel.FieldMapBase.Execute(WorkItemData source, WorkItemData target) dans D:\a\azure-devops-migration-tools\azure-devops-migration-tools\src\MigrationTools.Clients.TfsObjectModel\Tools\FieldMappingTool\FieldMaps\FieldMapBase.cs:ligne 35
Error logged to Elmah.io!
!! Check for latest version - We fix issues constantly - If not, please create a discussion on https://github.com/nkdAgility/azure-devops-migration-tools/discussions so we can get this fixed !!

What happened?

For some historical reason, the value Microsoft.VSTS.Common.Priority is set to null for a revision, and the null value is not handled by the FieldValueMap class

null must be handled and treated as "null"

Debug in Visual Studio

• Visual Studio Debug