JSON source generator fails with recursive collection type graphs

[layomia]

The generator fails to handle types such as the following. Failure mode is a runtime stack overflow. New API is likely needed to correctly handle this (hopefully rare) scenario, given that lazy initialization of element type metadata is required:

public class MyClass : List<MyClass> { }

See [ActiveIssue] additions in #66422 for more (complicated) examples.

[ghost]

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Issue Details

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The generator fails to handle types such as the following. Failure mode is a runtime stack overflow. New API is likely needed to correctly handle this (hopefully rare) scenario, given that lazy initialization of element type metadata is required:

public class MyClass : List<MyClass> { }

Author:	layomia
Assignees:	-
Labels:	bug, area-System.Text.Json, source-generator
Milestone:	7.0.0

[eiriktsarpalis]

Failure mode is a runtime stack overflow.

Does this specifically concern fast path serialization? Can you share a repro?

[krwq]

I fixed this accidentally in 897b2a3#diff-b7da6b90947be2bdebc35f367d9dc2c5bb66dd3be881af8a2d6cbb9c18108a7fL528

since that was required for contract customization to work correctly. I'll send PR shortly to re-enable the tests