Feature | Fix enhanced routing ack handling.

[mdaigle]

Ports #3922 to main

[Copilot]

Pull request overview

This pull request fixes the handling of enhanced routing acknowledgment in SQL Server connections. The PR ensures that enhanced routing information (which includes a database name) is only used when the server explicitly acknowledges support for the FEATUREEXT_ENHANCEDROUTINGSUPPORT feature extension. If the server doesn't acknowledge the feature or explicitly disables it, the routing information is ignored and the connection stays with the current server.

Changes:

• Added validation logic to ignore enhanced routing info when DatabaseName is present but IsEnhancedRoutingSupportEnabled is false
• Updated OnFeatureExtAck to process enhanced routing feature acknowledgment even during routing
• Refactored unit tests to use a helper class pattern and cover both sync and async code paths

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
src/Microsoft.Data.SqlClient/src/Microsoft/Data/SqlClient/Connection/SqlConnectionInternal.cs	Added enhanced routing acknowledgment validation in LoginNoFailover and LoginWithFailover methods; updated OnFeatureExtAck to allow processing of enhanced routing feature
src/Microsoft.Data.SqlClient/tests/UnitTests/SimulatedServerTests/ConnectionEnhancedRoutingTests.cs	Refactored tests to use TestRoutingServers helper class; converted to Theory-based tests covering sync/async paths and multiple server behaviors

[Copilot]

The use of continue here is inconsistent with the equivalent logic in LoginNoFailover (line 3299), which uses break. Both are functionally equivalent since RoutingInfo is set to null immediately before, but break is more explicit and clearer about the intent to exit the routing loop. Consider changing continue to break for consistency.

Suggested change

	continue;
	break;

[paulmedynski]

/azp run

[azure-pipelines]

Azure Pipelines will not run the associated pipelines, because the pull request was updated after the run command was issued. Review the pull request again and issue a new run command.

The base branch was changed.

[mdaigle]

RoutingTdsServers always send a routing or enhanced routing envchange token. They only acknowledge the feature extension based on the specific feature extension behavior.

[codecov]

Codecov Report

❌ Patch coverage is 53.33333% with 7 lines in your changes missing coverage. Please review.
✅ Project coverage is 64.58%. Comparing base (8a22d4f) to head (28f7ef2).
⚠️ Report is 4 commits behind head on main.

Files with missing lines	Patch %	Lines
...Data/SqlClient/Connection/SqlConnectionInternal.cs	53.33%	7 Missing ⚠️

❗ There is a different number of reports uploaded between BASE (8a22d4f) and HEAD (28f7ef2). Click for more details.

HEAD has 1 upload less than BASE

Flag	BASE (8a22d4f)	HEAD (28f7ef2)
CI-SqlClient	1	0

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3973      +/-   ##
==========================================
- Coverage   74.20%   64.58%   -9.63%     
==========================================
  Files         287      282       -5     
  Lines       43881    66034   +22153     
==========================================
+ Hits        32562    42645   +10083     
- Misses      11319    23389   +12070     

Flag	Coverage Δ
CI-SqlClient	?
PR-SqlClient-Project	64.58% <53.33%> (?)

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.