[NETSDKE2E][Regression]Error: Failed to load template from "C:\xxx\microsoft.maui.templates.net10.10.0.20.nupkg(/content/templates/maui-blazor-solution/.template.config/template.json)" displays when running command in CLI for the first time.

[vdanche]

RGRESSION INFO
not repro on VS 18.6 Insiders [11617.261.main] + 11.0.100-preview.3.26166.111 (runtime- 11.0.0-preview.3.26166.111)
not repro in CLI when only installed Insiders VS 18.6 [11618.325.main]

INSTALL STEPS

Insiders VS 18.6 [11618.325.main] + 11.0.100-preview.3.26168.106 (runtime- 11.0.100-preview.3.26168.106) on win-x64

REPRO STEPS
1.In CLI, run the dotnet command for the first time, e.g dotnet new sln

ACTUAL
sln is created successfully,but below error happens

Error: Failed to load template from "C:\Program Files\dotnet\template-packs\microsoft.maui.templates.net10.10.0.20.nupkg(/content/templates/maui-blazor-solution/.template.config/template.json)".
Details: System.ArgumentException: An item with the same key has already been added. Key: empty (Parameter 'key')
at System.Collections.ThrowHelper.ThrowDuplicateKey[TKey](TKey key)
at System.Collections.Generic.OrderedDictionary2.TryInsert(Int32 index, TKey key, TValue value, InsertionBehavior behavior, Int32& keyIndex) at System.Collections.Generic.OrderedDictionary2.Add(TKey key, TValue value)
at System.Text.Json.Nodes.JsonObject.InitializeDictionary()
at System.Text.Json.Nodes.JsonObject.get_Count()
at System.Collections.Generic.List1..ctor(IEnumerable1 collection)
at System.Linq.Enumerable.ToList[TSource](IEnumerable1 source) at Microsoft.TemplateEngine.Orchestrator.RunnableProjects.ConfigModel.TemplateConfigModel..ctor(JsonObject source, ILogger logger, String baselineName) at Microsoft.TemplateEngine.Orchestrator.RunnableProjects.DirectoryBasedTemplate..ctor(IEngineEnvironmentSettings settings, IGenerator generator, IFile templateFile, String baselineName) at Microsoft.TemplateEngine.Orchestrator.RunnableProjects.RunnableProjectGenerator.GetTemplatesFromMountPointInternalAsync(IMountPoint source, CancellationToken cancellationToken) Error: Failed to load template from "C:\Program Files\dotnet\template-packs\microsoft.maui.templates.net10.10.0.20.nupkg(/content/templates/maui-blazor/.template.config/template.json)". Details: System.ArgumentException: An item with the same key has already been added. Key: empty (Parameter 'key') at System.Collections.ThrowHelper.ThrowDuplicateKey[TKey](TKey key) at System.Collections.Generic.OrderedDictionary2.TryInsert(Int32 index, TKey key, TValue value, InsertionBehavior behavior, Int32& keyIndex)
at System.Collections.Generic.OrderedDictionary2.Add(TKey key, TValue value) at System.Text.Json.Nodes.JsonObject.InitializeDictionary() at System.Text.Json.Nodes.JsonObject.get_Count() at System.Collections.Generic.List1..ctor(IEnumerable1 collection) at System.Linq.Enumerable.ToList[TSource](IEnumerable1 source)
at Microsoft.TemplateEngine.Orchestrator.RunnableProjects.ConfigModel.TemplateConfigModel..ctor(JsonObject source, ILogger logger, String baselineName)
at Microsoft.TemplateEngine.Orchestrator.RunnableProjects.DirectoryBasedTemplate..ctor(IEngineEnvironmentSettings settings, IGenerator generator, IFile templateFile, String baselineName)
at Microsoft.TemplateEngine.Orchestrator.RunnableProjects.RunnableProjectGenerator.GetTemplatesFromMountPointInternalAsync(IMountPoint source, CancellationToken cancellationToken)

Expected Result:
sln is created successfully without any erros

Note:
1.We don't meet it in CLI when only installing SDK
2.it not happens when running command in CLI for the second time

[NicoleWang001]

I also met the issue with .NET 11.0.100-preview.3.26172.107 on Fedora 43 Linux

[balachir]

@marcpopMSFT is this an issue in the .NET SDK that needs to be looked at for .NET 11 P3? From Nicole's scenario above, this reproduces when only .NET SDK is installed and even the install of VS is not necessary.

[marcpopMSFT]

Moving to templating because that's where the callstack is from.

[marcpopMSFT]

same as #10025

[marcpopMSFT]

This will need to flow to dotnet/dotnet and get a new build before it can be tested E2E

[vdanche]

currently the fix is not mergered into 11.0.100-preview.3.26174.105 SDK, will verify on the new build.