Exclude properties of delegate types in configuration source generator

[tarekgh]

Presently, the configuration source generator generates binding code for properties employing delegate, Func, or Action types. However, there is no means to bind configuration to such types. Consequently, the generator generates an abundance of code for all types associated with these delegates, many of which will not be utilized and may lead to code that does not compile. Here's an example:

https://github.com/dotnet/extensions/blob/14943b99572078f1bcf2c51e9507cf2631133fae/src/Libraries/Microsoft.Extensions.Resilience/Resilience/Internal/FailureEventMetricsOptions.cs#L11

This issue is tracking to fix the source generator to skip generating any code for such properties or types.

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Issue Details

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Presently, the configuration source generator generates binding code for option properties employing delegate, Func, or Action types. However, there is no means to bind configuration to such types. Consequently, the generator generates an abundance of code for all types associated with these delegates, many of which will not be utilized and may lead to code that does not compile. Here's an example:

https://github.com/dotnet/extensions/blob/14943b99572078f1bcf2c51e9507cf2631133fae/src/Libraries/Microsoft.Extensions.Resilience/Resilience/Internal/FailureEventMetricsOptions.cs#L11

This issue is tracking to fix the source generator to skip generating any code for such properties or types.

Author:	tarekgh
Assignees:	-
Labels:	area-Extensions-Configuration
Milestone:	-

[tarekgh]

CC @eerhardt @ericstj

[ericstj]

We should match the exclusions used by JSON: https://github.com/dotnet/runtime/blob/9461f4b5bd036005f37e78516c48b13396f76750/src/libraries/System.Text.Json/gen/JsonSourceGenerator.Parser.cs#L1687C26-L1687C43

• SerializationInfo
• IntPtr / UIntPtr
• MemberInfo and derived types
• Delegate and derived type
• multi-dimensional arrays (already excluded)

These need to be excluded wherever they occur in the object graph including nullable, array, and collection members. They are OK to appear as generic parameters -- but should be excluded when appearing as members in such types.