Fix issue with nullable values not validated when value is null Bug: 20525

[janrhijn]

Fix for this #issue #20525. This change removes the if (utf8JsonReader.TokenType != JsonTokenType.Null) check and instead implements a ternary check utf8JsonReader.TokenType == JsonTokenType.Null ? null : utf8JsonReader.GetXXX() in the constructor of the Option. This results that when a property has a null value the Option is initialized (and IsSet = True, with Value = null) which fixes the validation for nullable properties with a null value.
From this:

case "int":
  if (utf8JsonReader.TokenType != JsonTokenType.Null)
    varInt = new Option<int?>(utf8JsonReader.GetInt32());
  break;

to this

case "int":
  varInt = new Option<int?>(utf8JsonReader.TokenType == JsonTokenType.Null ? null : utf8JsonReader.GetInt32());
  break;

File with code change: modules/openapi-generator/src/main/resources/csharp/libraries/generichost/JsonConverter.mustache

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[devhl-labs]

Looks good, please resolve the conflicts @janrhijn

[janrhijn]

Looks good, please resolve the conflicts @janrhijn

I have resolved the conflicts

[wing328]

can you please review the CI test failure when you've time?

[janrhijn]

can you please review the CI test failure when you've time?

Fixed!
In order to fix the Target-Typed Conditional Expression are not supported (CS8957) error, I explicitly cast the null to the specific type:

case "int":
  varInt = new Option<int?>(utf8JsonReader.TokenType == JsonTokenType.Null ? (int?)null : utf8JsonReader.GetInt32());
  break;

[marcselman]

It looks like this fix is ready to be merged.
I'm waiting for this fix since I am experiencing the same issue.
When can we expect this to be released?

[wing328]

all tests (with updated samples) passed via #20951