Fix .Update() marking AfterSaveBehavior.Throw properties as modified via DetectChanges#38115
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AndriySvyryd merged 6 commits intomainfrom Apr 16, 2026
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…s during Update() to prevent DetectChanges from re-marking them as modified In SetEntityState with modifyProperties=true, after unflagging Throw properties, also ensure their original values match current values. This prevents DetectChanges from finding false mismatches due to snapshot factories storing default values for shadow properties on complex types. Agent-Logs-Url: https://github.com/dotnet/efcore/sessions/226e05b5-79be-4c42-9c60-b85c45bcf703 Co-authored-by: AndriySvyryd <6539701+AndriySvyryd@users.noreply.github.com>
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Pull request overview
Fixes a regression where DbContext.Update() combined with DetectChanges can re-mark AfterSaveBehavior.Throw properties (notably the complex-type discriminator shadow property) as modified, causing SaveChanges to throw for optional complex types.
Changes:
- Update
InternalEntryBase.SetEntityStateto synchronize original values forAfterSaveBehavior.Throwproperties with current values to prevent false mismatches duringDetectChanges. - Add a regression test covering
Update()on an entity with a nullable complex type discriminator to ensureSaveChangesAsyncsucceeds.
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Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.
| File | Description |
|---|---|
| src/EFCore/ChangeTracking/Internal/InternalEntryBase.cs | Adjusts state-setting logic to prevent DetectChanges from re-marking Throw properties as modified due to snapshot/current mismatches. |
| test/EFCore.Specification.Tests/Query/AdHocComplexTypeQueryTestBase.cs | Adds a regression test validating Update() + optional complex type discriminator no longer throws on save. |
…move second pass Agent-Logs-Url: https://github.com/dotnet/efcore/sessions/920653c7-9690-47d4-8d9d-10857f722725 Co-authored-by: AndriySvyryd <6539701+AndriySvyryd@users.noreply.github.com>
…lex_type_and_discriminator_does_not_throw Agent-Logs-Url: https://github.com/dotnet/efcore/sessions/c4bbf4d0-14d6-4657-8eff-040197cda3bb Co-authored-by: AndriySvyryd <6539701+AndriySvyryd@users.noreply.github.com>
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@AndriySvyryd is this something we need to service?
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I think it's a corner case as we only had one report since 10.0.3 |
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Fixes #38105
DbContext.Update()on an entity with a nullable complex type + discriminator throws duringSaveChanges:Regression from #37394: the snapshot factory stores default values for shadow properties on complex types, so
DetectChangesfinds a false mismatch between the current discriminator value (set by value generator) and the snapshot (null), re-marking theThrowproperty as modified afterSetEntityStatecorrectly unflagged it.Changes
InternalEntryBase.SetEntityState: In themodifyPropertiesblock, after unflaggingThrowproperties, set their original values to match current values (guarded by!IsConceptualNull(property)) inline in the same loop soDetectChangeswon't find a false mismatch and re-mark them as modified.Test: Added
Update_entity_with_nullable_complex_type_and_discriminator_does_not_throw— inserts entity with nullable complex type + discriminator, clears tracker, callsUpdate()with a new disconnected instance, assertsSaveChangesAsyncsucceeds.A more targeted fix is proposed in #38111, but I believe this is a more robust approach