[cheenamalhotra]

Description

Follow-up to #4810. Some string-based references still used old type names, so the compiler did not catch them. This PR fixes them and makes the affected test helpers fail fast.

• TdsParserStateObjectHelper: use Parser.TdsParserStateObjectManaged; on .NET, assert the type is found.
• FilteredDefaultTraceListener (stress): use Parser.* stack-frame names; validate frame names at startup.
• FedAuthTokenHelper:
  • Use Parser.Login.SqlFedAuthToken.
  • Fix GetTokenHash, which was already broken before Refactor TDS parser into focused namespaces and files #4810. It used a missing constructor and field, so it always returned "".
  • Remove the catch-all blocks so lookup errors are visible.
• tds-protocol.instructions.md: replace the deleted TdsParserHelperClasses.cs with Parser/Tokens/.
• TdsParserStateObject.cs: update a type name in a commented-out code example.

No product behavior changes.

Issues

Follow-up to #4810.

Testing

• dotnet build src/Microsoft.Data.SqlClient/tests/StressTests/SqlClient.Stress.Tests/SqlClient.Stress.Tests.csproj -f net10.0: passed, with 0 warnings.
• dotnet build src/Microsoft.Data.SqlClient/tests/ManualTests/Microsoft.Data.SqlClient.ManualTests.csproj -f net10.0: passed, with 0 warnings.
• A reflection check against the built net10.0 driver confirmed all three stack frames, the SqlFedAuthToken constructor and hash method, and TdsParserStateObjectManaged._sessionHandle resolve.
• Not run: net462 builds, and AADFedAuthTokenRefreshTest, which needs an Azure managed identity. That test now compares real token hashes instead of "", so it may surface real refresh behavior.

Guidelines

Please review the contribution guidelines before submitting a pull request:

• Contributing
• Code of Conduct
• Best Practices
• Coding Style
• Review Process

[Copilot]

🔵 Needs a closer look

.NET Framework compatibility and the managed-identity refresh test’s newly effective token-hash comparisons remain unverified.

No open issues 🎉

What changed in this PR

Repairs string-based references left behind by #4810’s TDS parser namespace move and makes affected test helpers fail fast. Product behavior remains unchanged.

Changes:

• Updates reflection type names and stress-test stack-frame filters, adding lookup validation.
• Repairs token hashing and removes catch-all blocks that hid reflection failures.
• Updates the protocol guide and a commented-out reflection example.

File	Description
src/​Microsoft.Data.SqlClient/​tests/​StressTests/​SqlClient.Stress.Tests/​FilteredDefaultTraceListener.cs	Updates parser frame names and validates their targets.
src/​Microsoft.Data.SqlClient/​tests/​ManualTests/​SQL/​Common/​SystemDataInternals/​TdsParserStateObjectHelper.cs	Corrects the managed parser type lookup and asserts availability on .NET.
src/​Microsoft.Data.SqlClient/​tests/​ManualTests/​SQL/​Common/​SystemDataInternals/​FedAuthTokenHelper.cs	Repairs token hashing and exposes reflection errors.
src/​Microsoft.Data.SqlClient/​src/​Microsoft/​Data/​SqlClient/​Parser/​TdsParserStateObject.cs	Corrects the type name in a commented-out example only.
.github/​instructions/​tds-protocol.instructions.md	Replaces the deleted helper-file reference with token-file documentation.

_{Review effort: Balanced}

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 67.15%. Comparing base (7b1184b) to head (1035a44).
⚠️ Report is 74 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4924      +/-   ##
==========================================
- Coverage   67.94%   67.15%   -0.79%     
==========================================
  Files         311      308       -3     
  Lines       45399    68824   +23425     
==========================================
+ Hits        30845    46219   +15374     
- Misses      14554    22605    +8051     

Flag	Coverage Δ
CI-SqlClient	?
PR-SqlClient-Project	67.15% <ø> (?)

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[priyankatiwari08]

One stale reflection name left in the sample (inline); other reflection lookups resolve at head.

[Copilot]

🔵 Needs a closer look

The refresh test can fail on a successful token refresh because it incorrectly requires the old and refreshed token hashes to match.

No open issues 🎉

1 previously missed issue

In code that hasn't changed since last review

Refresh test incorrectly requires identical token hashes

src/​Microsoft.Data.SqlClient/​tests/​ManualTests/​SQL/​Common/​SystemDataInternals/​FedAuthTokenHelper.cs:57

Returning the real hash exposes an invalid assertion in FedAuthTokenRefreshTest: it requires the old and refreshed hashes to be identical, although UserAssignedManagedIdentityProvider can acquire a new token. A successful refresh can therefore fail the test solely because the token changed. Update AADFedAuthTokenRefreshTest.cs to verify provider invocation and a later cache expiry without requiring identical token hashes.

_{Review effort: Balanced}