Skip to content

Fix TypeFactory.CreateCSharpType crash on self-referencing models #10060

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
JoshLove-msft merged 2 commits into from
Mar 17, 2026
Merged

Fix TypeFactory.CreateCSharpType crash on self-referencing models #10060

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
f7bab0f
Initial plan
Copilot Mar 17, 2026
580b05d
fix: use indexer assignment in TypeFactory.CreateCSharpType to handle…
Copilot Mar 17, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
2 changes: 1 addition & 1 deletion packages/http-client-csharp/generator/Microsoft.TypeSpec.Generator/src/TypeFactory.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -51,7 +51,7 @@ protected internal TypeFactory()
}

type = CreateCSharpTypeCore(inputType);
TypeCache.Add(inputType, type);
TypeCache[inputType] = type;
return type;
}

Expand Down
24 changes: 24 additions & 0 deletions packages/http-client-csharp/generator/Microsoft.TypeSpec.Generator/test/TypeFactoryTests.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -283,6 +283,30 @@ public void CreateEnum_ExtensibleEnumWithoutVisitorsOrCustomCode_ReturnsExtensib
Assert.IsTrue(enumProvider!.IsExtensible);
}

[Test]
public void CreateCSharpType_SelfReferencingModel_DoesNotThrow()
{
var selfRefModel = InputFactory.Model("QueryFilter");
var isReentrant = false;

MockHelpers.LoadMockGenerator(createCSharpTypeCore: (InputType inputType) =>
{
if (inputType == selfRefModel && !isReentrant)
{
isReentrant = true;
// Simulate the re-entrant call that occurs with self-referencing models
// (e.g., QueryFilter with property and: QueryFilter[]).
// CreateCSharpTypeCore -> CreateModel -> BuildProperties -> CreateCSharpType(same model)
CodeModelGenerator.Instance.TypeFactory.CreateCSharpType(selfRefModel);
}
return typeof(object);
});

// Before the fix, this would throw ArgumentException:
// "An item with the same key has already been added"
Assert.DoesNotThrow(() => CodeModelGenerator.Instance.TypeFactory.CreateCSharpType(selfRefModel));
}

/// <summary>
/// Test visitor that modifies enum namespaces to end with ".Models"
/// </summary>
Expand Down
Loading