Feature | Add support for enhanced routing feature extension.

[mdaigle]

Ports #3643 to main

[Copilot]

Pull request overview

This pull request adds support for the Enhanced Routing feature extension to the TDS protocol implementation. Enhanced Routing is a TDS 8.0 feature that allows SQL Server to negotiate advanced routing capabilities during connection establishment. The implementation follows the established pattern for feature extensions in Microsoft.Data.SqlClient.

Changes:

• Adds TDS protocol support for Enhanced Routing feature extension (ID 0x0F) with request/acknowledgment handling
• Implements test infrastructure to validate client-server feature negotiation with three scenarios (enabled, disabled, not acknowledged)
• Refactors TDS.Servers.csproj to remove explicit file enumeration, allowing SDK-style implicit compilation

Reviewed changes

Copilot reviewed 10 out of 10 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
src/Microsoft.Data.SqlClient/src/Microsoft/Data/SqlClient/TdsEnums.cs	Adds constant FEATUREEXT_ENHANCEDROUTINGSUPPORT (0x0F) and flag EnhancedRoutingSupport to FeatureExtension enum
src/Microsoft.Data.SqlClient/src/Microsoft/Data/SqlClient/TdsParser.cs	Implements WriteEnhancedRoutingSupportFeatureRequest to send feature request with no payload, adds call in ApplyFeatureExData
src/Microsoft.Data.SqlClient/src/Microsoft/Data/SqlClient/Connection/SqlConnectionInternal.cs	Adds IsEnhancedRoutingSupportEnabled flag, implements acknowledgment handler in OnFeatureExtAck, adds feature to login request
src/Microsoft.Data.SqlClient/tests/tools/TDS/TDS/TDSFeatureID.cs	Adds EnhancedRoutingSupport (0x0F) to test TDS feature ID enum
src/Microsoft.Data.SqlClient/tests/tools/TDS/TDS.Servers/FeatureExtensionEnablementTriState.cs	New enum for test server tri-state feature control (Disabled, Enabled, DoNotAcknowledge)
src/Microsoft.Data.SqlClient/tests/tools/TDS/TDS.EndPoint/ITDSServerSession.cs	Adds IsEnhancedRoutingSupportEnabled property to server session interface
src/Microsoft.Data.SqlClient/tests/tools/TDS/TDS.Servers/GenericTdsServerSession.cs	Implements IsEnhancedRoutingSupportEnabled property for test server sessions
src/Microsoft.Data.SqlClient/tests/tools/TDS/TDS.Servers/GenericTdsServer.cs	Adds EnableEnhancedRouting property, implements feature request handling in OnLogin7Request, adds CheckEnhancedRoutingSupport method for acknowledgment generation
src/Microsoft.Data.SqlClient/tests/UnitTests/SimulatedServerTests/FeatureExtensionNegotiationTests.cs	New test file with three test scenarios for enhanced routing negotiation (enabled, disabled, not acknowledged)
src/Microsoft.Data.SqlClient/tests/tools/TDS/TDS.Servers/TDS.Servers.csproj	Removes EnableDefaultCompileItems and explicit <Compile> elements to use SDK-style implicit file inclusion

[Copilot]

Pull request overview

Copilot reviewed 11 out of 11 changed files in this pull request and generated 4 comments.

[codecov]

Codecov Report

❌ Patch coverage is 78.57143% with 6 lines in your changes missing coverage. Please review.
✅ Project coverage is 64.45%. Comparing base (a68e00f) to head (9e9e950).
⚠️ Report is 14 commits behind head on main.

Files with missing lines	Patch %	Lines
...Data/SqlClient/Connection/SqlConnectionInternal.cs	62.50%	6 Missing ⚠️

❗ There is a different number of reports uploaded between BASE (a68e00f) and HEAD (9e9e950). Click for more details.

HEAD has 6 uploads less than BASE

Flag	BASE (a68e00f)	HEAD (9e9e950)
netfx	2	0
netcore	2	0
addons	2	0

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #3969       +/-   ##
===========================================
- Coverage   75.22%   64.45%   -10.77%     
===========================================
  Files         266      282       +16     
  Lines       42932    65951    +23019     
===========================================
+ Hits        32294    42512    +10218     
- Misses      10638    23439    +12801     

Flag	Coverage Δ
PR-SqlClient-Project	64.45% <78.57%> (?)
addons	?
netcore	?
netfx	?

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.