Unquarantine AddValidationIntegrationTest.FormWithNestedValidation_Works

[oroztocil]

Reverts c10ee0e (#68224), which quarantined AddValidationIntegrationTest.FormWithNestedValidation_Works.

The quarantine was based on stale CI data. The test is not flaky and MEV activation is not broken.

The cited failures are all from before the fix

Issue #68223 lists four failing builds. All of them ran on 2026-07-08, and none of them contain the fix commit 0c3e825607 (#67680), which merged on 2026-07-08 at 19:48 UTC.

Build	Queue time (UTC)	Commit	Contains #67680
1499278	2026-07-08 12:08	3e156e1a74 (#67636, the regression itself)	No
1499615	2026-07-08 14:22	12fe5679d8	No
1499768	2026-07-08 15:50	4b9040ecc8	No
1500081	2026-07-08 19:20	cb1ac26bbd	No

These are the same builds already tracked by #67699, which was closed once #67680 merged. Issue #68223 effectively re-filed an already resolved problem a month later.

For contrast, the sibling issue #68226, generated by the same Daily Test Quarantine Management workflow run, cites genuinely recent builds (1531284, 1537634). So only this one issue picked up stale data.

The original failure was deterministic, not a race

Both #67699 and #68223 describe the failure as a timing or rendering race. It was not.

PR #67636 removed generator discovery of Microsoft.Extensions.Validation.Embedded.ValidatableTypeAttribute from ValidationsGenerator. The test model OrderModel was annotated with an unqualified [ValidatableType] that bound to that SDK embedded attribute, so after #67636 the generator stopped emitting validatable type info for it.

Without a source generated resolver, DataAnnotationsValidator fell back to the plain System.ComponentModel.DataAnnotations.Validator path, which does not recurse into nested complex properties. That produces exactly the observed result: only the top level Order Name is required. message, and nothing from CustomerModel, AddressModel, or OrderItemModel.

PR #67680 fixed it by fully qualifying the attribute to [Microsoft.Extensions.Validation.ValidatableType]. That annotation is still in place today (src/Components/test/testassets/Components.TestServer/RazorComponents/ValidationModels/OrderModel.cs), and ValidationsGenerator.cs still discovers Microsoft.Extensions.Validation.ValidatableTypeAttribute.

Separately, #67702 added src/Validation/* to the aspnetcore-components-e2e path triggers, so MEV changes now run these E2E tests on the PR.

The test has been green since

Across all 127 aspnetcore-components-e2e builds on main between 2026-07-09 and the quarantine on 2026-08-05, FormWithNestedValidation does not appear in any build log. The test name is only emitted on failure, so zero occurrences means zero failures.

The 17 builds that failed in that window failed for unrelated reasons: Mono leg failures, 120 minute agent timeouts, and other already quarantined tests.

Spot checks immediately before the quarantine:

Build	Date	Result
1538405	2026-08-03	Run E2E tests passed, only quarantined legs failed
1540079	2026-08-04	Run E2E tests passed, only quarantined legs failed
1540791	2026-08-05 12:55	Run E2E tests passed, only quarantined legs failed

And after the quarantine landed, 1541387 (2026-08-05 18:07, includes c10ee0eb58) ran the test in the quarantined leg and it passed there too.

Change

Removes the [QuarantinedTest] attribute and the now unused Microsoft.AspNetCore.InternalTesting using directive.

Closes #68223

[Copilot]

Pull request overview

This pull request unquarantines AddValidationIntegrationTest.FormWithNestedValidation_Works by removing the quarantine attribute that was added based on stale CI failure data, restoring the test to the normal (non-quarantined) test run.

Changes:

• Removed the [QuarantinedTest(...)] attribute from FormWithNestedValidation_Works.
• Removed the now-unused Microsoft.AspNetCore.InternalTesting using directive.

[oroztocil]

Let's merge this on Monday so we avoid the bot spawning the issue again. Last failure will be > 30 days ago on Monday.