SystemTextSerializer: Fixes serialization type in ToStream method#5517
Merged
Conversation
Use `typeof(T)` instead of `input.GetType()` to preserve polymorphic serialization. When T is a base type with `[JsonPolymorphic]`, this ensures the `$type` discriminator is included. Using `input.GetType()` would serialize as the concrete type, bypassing polymorphic attributes.
jaliyaudagedara
requested review from
FabianMeiswinkel,
adityasa,
khdang,
kirankumarkolli,
kirillg,
neildsh and
sboshra
as code owners
…erializer Added unit tests to verify polymorphic serialization behavior when using typeof(T) instead of input.GetType() in the ToStream method. Tests validate that the $type discriminator is correctly included when serializing derived types through a base type parameter, which is required for proper polymorphic deserialization.
Praveen-Msft
reviewed
Dec 2, 2025
kirankumarkolli
approved these changes
Dec 9, 2025
kirankumarkolli
changed the title
Member
|
/azp run |
|
Azure Pipelines successfully started running 1 pipeline(s). |
kundadebdatta
approved these changes
Dec 10, 2025
Member
|
/azp run |
|
Azure Pipelines successfully started running 1 pipeline(s). |
Member
|
/azp run |
|
Azure Pipelines successfully started running 1 pipeline(s). |
kirankumarkolli
approved these changes
Dec 17, 2025
This was referenced Mar 23, 2026
Bump Microsoft.Azure.Cosmos from 3.57.1 to 3.58.0
azureossd/general-database-connectivity-samples#27
Merged
Merged
This was referenced Apr 7, 2026
This was referenced Apr 20, 2026
This was referenced Apr 27, 2026
Open
This was referenced May 4, 2026
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
4 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Description
Use
typeof(T)instead ofinput.GetType()to preserve polymorphic serialization. When T is a base type with[JsonPolymorphic], this ensures the$typediscriminator is included. Usinginput.GetType()would serialize as the concrete type, bypassing polymorphic attributes..Type of change
Please delete options that are not relevant.