Refactor TDS parser into focused namespaces and files by benrr101 · Pull Request #4675 · dotnet/SqlClient

benrr101 · 2026-09-10T23:54:22Z

Description

Refactors the TDS parser implementation into focused files and namespaces without changing its public API or intended behavior.

Splits helper types, enums, safe handles, parser state, and related classes out of the large legacy source files.
Moves parser implementation types under Microsoft.Data.SqlClient.Parser.
Groups login and token-related types under Parser.Login and Parser.Tokens.
Preserves file history through step-wise moves so reviewers can distinguish relocation from structural cleanup.
Updates internal references and affected tests for the new namespaces.

This is layer 1 of 3 in the TDS parser organization stack and targets main.

Issues

No linked issue; this is an internal code-organization refactor.

Testing

No behavior change is intended. Existing functional and unit test sources were updated to use the reorganized parser namespaces; CI will exercise the supported target frameworks and platforms.

Guidelines

Copilot

🔵 Needs a closer look

Several manual and stress tests retain obsolete reflected type and stack-frame names and will fail or stop filtering correctly.

Pull request overview

Refactors internal TDS parser types into focused Parser, Parser.Login, and Parser.Tokens namespaces without intended public API changes.

Changes:

Splits parser helpers, metadata, login, token, and native-handle types into dedicated files.
Updates production and test imports for the new namespaces.
Relocates existing public enums into standalone files.

File summaries

File	Description
`tests/UnitTests/TdsParserInternalsTest.cs`	Imports parser namespace.
`tests/UnitTests/SimulatedServerTests/TdsTokenBoundsTests.cs`	Imports parser namespace.
`tests/UnitTests/SimulatedServerTests/FeatureExtAckBoundsTests.cs`	Imports parser namespace.
`tests/UnitTests/Microsoft/Data/SqlClient/TdsParserStateObjectNativeTests.cs`	Imports parser namespace.
`tests/UnitTests/Microsoft/Data/SqlClient/StateSnapshotPacketRecyclingTests.cs`	Imports parser namespace.
`tests/UnitTests/Microsoft/Data/SqlClient/SqlMetaDataSetTest.cs`	Imports token namespace.
`tests/UnitTests/Microsoft/Data/SqlClient/ManagedSni/SniPacketTests.cs`	Imports parser namespace.
`tests/UnitTests/Microsoft/Data/Common/AdapterUtilTest.cs`	Imports parser namespace.
`tests/FunctionalTests/TdsParserStateObject.TestHarness.cs`	Moves harness into parser namespace.
`tests/FunctionalTests/MultiplexerTests.cs`	Imports parser namespace.
`tests/FunctionalTests/Microsoft.Data.SqlClient.FunctionalTests.csproj`	Updates relocated source paths.
`src/Microsoft/Data/SqlTypes/SqlVector.cs`	Imports parser namespace.
`src/Microsoft/Data/SqlClient/TransparentNetworkResolutionState.cs`	Extracts TNIR state enum.
`src/Microsoft/Data/SqlClient/TransactionRequest.cs`	Imports parser namespace.
`src/Microsoft/Data/SqlClient/TdsParserHelperClasses.cs`	Removes split-out helper definitions.
`src/Microsoft/Data/SqlClient/TdsParameterSetter.cs`	Removes relocated setter.
`src/Microsoft/Data/SqlClient/SSPI/SspiContextProvider.cs`	Imports parser namespace.
`src/Microsoft/Data/SqlClient/SSPI/NativeSspiContextProvider.cs`	Imports parser namespace.
`src/Microsoft/Data/SqlClient/SqlUtil.cs`	Imports parser namespace.
`src/Microsoft/Data/SqlClient/SqlTransaction.cs`	Imports parser namespace.
`src/Microsoft/Data/SqlClient/SqlSecurityUtility.cs`	Imports parser namespace.
`src/Microsoft/Data/SqlClient/SqlParameter.cs`	Imports parser and token namespaces.
`src/Microsoft/Data/SqlClient/SqlMetaDataFactory.DataTypes.cs`	Imports parser namespace.
`src/Microsoft/Data/SqlClient/SqlInternalTransaction.cs`	Imports parser namespace.
`src/Microsoft/Data/SqlClient/SqlEnvChange.cs`	Imports token namespace.
`src/Microsoft/Data/SqlClient/SqlEnums.cs`	Imports parser namespace.
`src/Microsoft/Data/SqlClient/SqlDbColumn.cs`	Imports parser metadata types.
`src/Microsoft/Data/SqlClient/SqlDataReader.cs`	Imports parser metadata types.
`src/Microsoft/Data/SqlClient/SqlCredential.cs`	Imports parser namespace.
`src/Microsoft/Data/SqlClient/SqlConnectionStringBuilder.cs`	Imports parser namespace.
`src/Microsoft/Data/SqlClient/SqlConnectionOverrides.cs`	Extracts public enum.
`src/Microsoft/Data/SqlClient/SqlConnectionOptions.cs`	Imports parser namespace.
`src/Microsoft/Data/SqlClient/SqlConnectionIPAddressPreference.cs`	Extracts public enum.
`src/Microsoft/Data/SqlClient/SqlConnectionColumnEncryptionSetting.cs`	Extracts public enum.
`src/Microsoft/Data/SqlClient/SqlConnectionAttestationProtocol.cs`	Extracts public enum.
`src/Microsoft/Data/SqlClient/SqlConnection.cs`	Imports parser types.
`src/Microsoft/Data/SqlClient/SqlCommandColumnEncryptionSetting.cs`	Extracts public enum.
`src/Microsoft/Data/SqlClient/SqlCommand.Xml.cs`	Imports parser namespace.
`src/Microsoft/Data/SqlClient/SqlCommand.Scalar.cs`	Imports parser namespace.
`src/Microsoft/Data/SqlClient/SqlCommand.Reader.cs`	Imports parser namespace.
`src/Microsoft/Data/SqlClient/SqlCommand.NonQuery.cs`	Imports parser namespace.
`src/Microsoft/Data/SqlClient/SqlCommand.Encryption.cs`	Imports parser namespace.
`src/Microsoft/Data/SqlClient/SqlCommand.cs`	Imports parser and token namespaces.
`src/Microsoft/Data/SqlClient/SqlCommand.Batch.cs`	Imports parser namespace.
`src/Microsoft/Data/SqlClient/SqlCollation.cs`	Imports parser namespace.
`src/Microsoft/Data/SqlClient/SqlCachedBuffer.cs`	Imports parser metadata types.
`src/Microsoft/Data/SqlClient/SqlBulkCopy.cs`	Imports parser metadata types.
`src/Microsoft/Data/SqlClient/SqlBuffer.cs`	Imports parser namespace.
`src/Microsoft/Data/SqlClient/Server/ValueUtilsSmi.cs`	Imports parser namespace.
`src/Microsoft/Data/SqlClient/Server/MetadataUtilsSmi.cs`	Imports parser namespace.
`src/Microsoft/Data/SqlClient/Parser/Tokens/SqlReturnValue.cs`	Extracts return-value metadata.
`src/Microsoft/Data/SqlClient/Parser/Tokens/SqlMetaDataXmlSchemaCollection.cs`	Extracts XML metadata.
`src/Microsoft/Data/SqlClient/Parser/Tokens/SqlMetaDataUdt.cs`	Extracts UDT metadata.
`src/Microsoft/Data/SqlClient/Parser/Tokens/SqlMetaDataPriv.cs`	Consolidates private metadata.
`src/Microsoft/Data/SqlClient/Parser/Tokens/SqlFedAuthInfo.cs`	Extracts federated-auth token data.
`src/Microsoft/Data/SqlClient/Parser/Tokens/RoutingInfo.cs`	Extracts routing token data.
`src/Microsoft/Data/SqlClient/Parser/Tokens/MultiPartTableName.cs`	Extracts multipart-name parsing.
`src/Microsoft/Data/SqlClient/Parser/Tokens/_SqlMetaDataSetCollection.cs`	Extracts metadata collection.
`src/Microsoft/Data/SqlClient/Parser/Tokens/_SqlMetaDataSet.cs`	Consolidates metadata-set logic.
`src/Microsoft/Data/SqlClient/Parser/Tokens/_SqlMetaData.cs`	Extracts column metadata.
`src/Microsoft/Data/SqlClient/Parser/TdsValueSetter.cs`	Moves value writer into parser namespace.
`src/Microsoft/Data/SqlClient/Parser/TdsRecordBufferSetter.cs`	Moves record writer into parser namespace.
`src/Microsoft/Data/SqlClient/Parser/TdsParserStaticMethods.cs`	Moves parser utilities.
`src/Microsoft/Data/SqlClient/Parser/TdsParserStateObjectNative.cs`	Moves native parser state.
`src/Microsoft/Data/SqlClient/Parser/TdsParserStateObjectManaged.netcore.cs`	Moves managed parser state.
`src/Microsoft/Data/SqlClient/Parser/TdsParserStateObjectFactory.cs`	Moves parser-state factory.
`src/Microsoft/Data/SqlClient/Parser/TdsParserStateObject.Multiplexer.cs`	Moves multiplexer implementation.
`src/Microsoft/Data/SqlClient/Parser/TdsParserStateObject.cs`	Moves core parser state.
`src/Microsoft/Data/SqlClient/Parser/TdsParserState.cs`	Extracts parser-state enum.
`src/Microsoft/Data/SqlClient/Parser/TdsParserSessionPool.cs`	Moves session pool.
`src/Microsoft/Data/SqlClient/Parser/TdsParser.cs`	Moves core parser.
`src/Microsoft/Data/SqlClient/Parser/TdsParameterSetter.cs`	Relocates parameter setter.
`src/Microsoft/Data/SqlClient/Parser/TdsOperationsStatus.cs`	Extracts operation-status enum.
`src/Microsoft/Data/SqlClient/Parser/SslProtocolHelper.cs`	Extracts TLS warning helper.
`src/Microsoft/Data/SqlClient/Parser/SNIPacket.cs`	Extracts native packet handle.
`src/Microsoft/Data/SqlClient/Parser/SNILoadHandle.cs`	Moves native SNI loader.
`src/Microsoft/Data/SqlClient/Parser/SNIHandle.cs`	Extracts native connection handle.
`src/Microsoft/Data/SqlClient/Parser/SniContext.cs`	Extracts SNI context enum.
`src/Microsoft/Data/SqlClient/Parser/SessionHandle.netfx.cs`	Moves .NET Framework session handle.
`src/Microsoft/Data/SqlClient/Parser/SessionHandle.netcore.cs`	Moves .NET session handle.
`src/Microsoft/Data/SqlClient/Parser/RunBehavior.cs`	Extracts parser run behavior.
`src/Microsoft/Data/SqlClient/Parser/ParsingErrorState.cs`	Extracts parsing-error enum.
`src/Microsoft/Data/SqlClient/Parser/PacketHandle.netfx.cs`	Moves .NET Framework packet handle.
`src/Microsoft/Data/SqlClient/Parser/PacketHandle.netcore.cs`	Moves .NET packet handle.
`src/Microsoft/Data/SqlClient/Parser/Packet.cs`	Moves packet reconstruction helper.
`src/Microsoft/Data/SqlClient/Parser/Login/SqlLogin.cs`	Extracts login state.
`src/Microsoft/Data/SqlClient/Parser/Login/SqlFedAuthToken.cs`	Extracts federated-auth token.
`src/Microsoft/Data/SqlClient/Parser/Login/PreLoginOptions.cs`	Extracts pre-login options.
`src/Microsoft/Data/SqlClient/Parser/Login/PreLoginHandshakeStatus.cs`	Extracts handshake status.
`src/Microsoft/Data/SqlClient/Parser/Login/FederatedAuthenticationFeatureExtensionData.cs`	Extracts federated-auth extension data.
`src/Microsoft/Data/SqlClient/Parser/Login/EncryptionOptions.cs`	Extracts encryption options.
`src/Microsoft/Data/SqlClient/Parser/LastIOTimer.cs`	Extracts I/O timer holder.
`src/Microsoft/Data/SqlClient/Parser/DescribeParameterEncryptionResultSet3.cs`	Extracts third result-set ordinals.
`src/Microsoft/Data/SqlClient/Parser/DescribeParameterEncryptionResultSet2.cs`	Extracts second result-set ordinals.
`src/Microsoft/Data/SqlClient/Parser/DescribeParameterEncryptionResultSet1.cs`	Extracts first result-set ordinals.
`src/Microsoft/Data/SqlClient/Parser/CallbackType.cs`	Extracts callback enum.
`src/Microsoft/Data/SqlClient/Parser/_SqlRPC.cs`	Extracts RPC state.
`src/Microsoft/Data/SqlClient/ManagedSni/SslOverTdsStream.netcore.cs`	Imports parser constants.
`src/Microsoft/Data/SqlClient/ManagedSni/SniTcpHandle.netcore.cs`	Imports parser types.
`src/Microsoft/Data/SqlClient/ManagedSni/SniProxy.netcore.cs`	Imports parser types.
`src/Microsoft/Data/SqlClient/ManagedSni/SniPacket.netcore.cs`	Imports parser types.
`src/Microsoft/Data/SqlClient/ManagedSni/SniNpHandle.netcore.cs`	Imports parser types.
`src/Microsoft/Data/SqlClient/ManagedSni/SniMarsHandle.netcore.cs`	Imports parser types.
`src/Microsoft/Data/SqlClient/ManagedSni/SniMarsConnection.netcore.cs`	Imports parser types.
`src/Microsoft/Data/SqlClient/ManagedSni/SniLoadHandle.netcore.cs`	Imports parser/login types.
`src/Microsoft/Data/SqlClient/ManagedSni/SniHandle.netcore.cs`	Imports parser types.
`src/Microsoft/Data/SqlClient/ManagedSni/SniError.netcore.cs`	Imports parser types.
`src/Microsoft/Data/SqlClient/ManagedSni/SniCommon.netcore.cs`	Imports parser types.
`src/Microsoft/Data/SqlClient/ManagedSni/LocalDB.netcore.cs`	Imports parser types.
`src/Microsoft/Data/SqlClient/LocalDb/LocalDbApi.cs`	Imports parser types.
`src/Microsoft/Data/SqlClient/Connection/SqlConnectionInternal.cs`	Imports parser, login, and token types.
`src/Microsoft/Data/SqlClient/Connection/ServerInfo.cs`	Imports parser routing types.
`src/Microsoft/Data/SqlClient/Connection/ConnectionCapabilities.cs`	Imports parser constants.
`src/Microsoft/Data/SqlClient/AlwaysEncryptedHelperClasses.cs`	Removes relocated metadata partials.
`src/Microsoft/Data/SqlClient/ActiveDirectoryAuthenticationTimeoutRetryHelper.cs`	Imports login token type.
`src/Microsoft/Data/Sql/SqlDataSourceEnumeratorNativeHelper.cs`	Imports parser types.
`src/Microsoft/Data/Common/AdapterUtil.cs`	Imports parser types.
`src/Interop/Windows/Sni/SniNativeWrapper.cs`	Imports relocated native handles.
`src/Interop/Windows/Sni/SniNativeMethodsX86.netfx.cs`	Imports parser handles.
`src/Interop/Windows/Sni/SniNativeMethodsX64.netfx.cs`	Imports parser handles.
`src/Interop/Windows/Sni/SniNativeMethodsNotSupported.netfx.cs`	Imports parser handles.
`src/Interop/Windows/Sni/SniNativeMethodsArm64.netfx.cs`	Imports parser handles.
`src/Interop/Windows/Sni/SniNativeMethods.netcore.cs`	Imports parser handles.
`src/Interop/Windows/Sni/ISniNativeMethods.cs`	Imports parser handles.

Review details

Suppressed comments (3)

src/Microsoft.Data.SqlClient/src/Microsoft/Data/SqlClient/Parser/TdsParser.cs:40

This namespace move leaves reflection consumers pointing at Microsoft.Data.SqlClient.TdsParser: ConnectionHelper.cs:52 and TdsParserHelper.cs:13 now receive null from Assembly.GetType (the former dereferences it during static initialization), and the stress-test filter at FilteredDefaultTraceListener.cs:84 no longer matches the new stack-frame name. Update those strings to Microsoft.Data.SqlClient.Parser.TdsParser as part of this move.
src/Microsoft.Data.SqlClient/src/Microsoft/Data/SqlClient/Parser/TdsParserStateObject.cs:28
Several reflection-based tests still request Microsoft.Data.SqlClient.TdsParserStateObject (ConnectionHelper.cs:57, TdsParserStateObjectHelper.cs:27, and MARSTest.cs:87/135). After this move, Assembly.GetType returns null, causing static-initializer assertion/null-reference failures; the stress filter at FilteredDefaultTraceListener.cs:85-86 also stops matching. Update all of these strings to the new Microsoft.Data.SqlClient.Parser.TdsParserStateObject name.
src/Microsoft.Data.SqlClient/src/Microsoft/Data/SqlClient/Parser/TdsParserStateObjectManaged.netcore.cs:21
TdsParserStateObjectHelper.cs:48 still reflects Microsoft.Data.SqlClient.ManagedSni.TdsParserStateObjectManaged. On .NET builds this now resolves to null; the helper treats that as framework absence and later throws when a managed session handle is requested. Update the reflected name to Microsoft.Data.SqlClient.Parser.TdsParserStateObjectManaged.

Files reviewed: 126/126 changed files
Comments generated: 0
Review effort level: Balanced

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edwardneal · 2026-09-11T05:15:14Z

This should be named SslProtocolsHelper.cs to match the containing type name.

edwardneal · 2026-09-11T05:15:29Z

This should be named TdsOperationStatus.cs to match the containing type name.

edwardneal · 2026-09-11T05:16:50Z

This, SNIPacket and SNIHandle are native SNI types, it should go in a new NativeSni namespace (to align with the existing ManagedSni one)

I like your thinking. This makes loads of sense to me, so despite it growing the scope of the changes in this PR, it's going in.

edwardneal · 2026-09-11T05:23:17Z

+    public const byte FEATUREEXT_USERAGENT = 0x10;
+
+    [Flags]
+    public enum FeatureExtension : uint


What's the rationale behind leaving these three enums in situ?

Basically ... TdsEnums was too much for me to look into 😅
Most of the file isn't actually enums, they're constants. Some of them should be enums, some of them are better off as constants. It seemed like a bigger change than I wanted to tackle with these mostly unoffensive changes.

Consolidate partial classes Add references to Parser namespace

Add references to Parser namespace

Add references where necessary

Move is made wholesale to preserve history

Moved wholesale to retain file history

Move TdsParserStateObjectManaged to Parser namespace

This creates a stub namespace that native SNI will go into

Copilot

🟡 Changes recommended

Reflection-based manual and stress tests still use the former parser type names, causing failures after the namespace migration.

Once you've addressed the issues Copilot identified, you can request another Copilot review.

Review details

Suppressed comments (3)

src/Microsoft.Data.SqlClient/src/Microsoft/Data/SqlClient/Parser/TdsParser.cs:40

The namespace move was not propagated to reflection-based test infrastructure. tests/ManualTests/SQL/Common/SystemDataInternals/ConnectionHelper.cs:52 and TdsParserHelper.cs:13 still request Microsoft.Data.SqlClient.TdsParser; Assembly.GetType now returns null and their static field initialization dereferences it. Update those type-name strings to Microsoft.Data.SqlClient.Parser.TdsParser; the stress-test frame filter at FilteredDefaultTraceListener.cs:84 also needs the new prefix.
src/Microsoft.Data.SqlClient/src/Microsoft/Data/SqlClient/Parser/TdsParserStateObject.cs:28
Several manual tests still resolve Microsoft.Data.SqlClient.TdsParserStateObject by name (MARSTest.cs:87,135, ConnectionHelper.cs:57, and TdsParserStateObjectHelper.cs:27). After this move those lookups return null, and the subsequent GetField calls or assertions fail. Update all reflection strings and the stress-test stack-frame entries to Microsoft.Data.SqlClient.Parser.TdsParserStateObject.
src/Microsoft.Data.SqlClient/src/Microsoft/Data/SqlClient/Parser/TdsParserStateObjectManaged.netcore.cs:21
TdsParserStateObjectHelper.cs:48 still looks up this type as Microsoft.Data.SqlClient.ManagedSni.TdsParserStateObjectManaged. The lookup now returns null, so GetSessionHandle throws “Library being tested does not implement TdsParserStateObjectManaged” for the managed implementation. Update the reflection string to Microsoft.Data.SqlClient.Parser.TdsParserStateObjectManaged.

Files reviewed: 126/126 changed files
Comments generated: 1
Review effort level: Balanced (auto)

Note

Copilot is running an experiment and ran this review at Balanced.

+using System;
+using System.Data;
+
+namespace Microsoft.Data.SqlClient.Parser.Tokens;


Copilot AI balanced review requested due to automatic review settings September 10, 2026 23:54

benrr101 requested a review from a team as a code owner September 10, 2026 23:54

github-project-automation Bot added this to SqlClient Board Sep 10, 2026

github-project-automation Bot moved this to To triage in SqlClient Board Sep 10, 2026

Copilot started reviewing on behalf of benrr101 September 10, 2026 23:54 View session

benrr101 added this pull request to stack #4678 September 10, 2026 23:55

Copilot AI reviewed Sep 10, 2026

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edwardneal reviewed Sep 11, 2026

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benrr101 added 11 commits September 11, 2026 11:48

Split TdsParserHelperClasses into separate files

cf279c7

Consolidate partial classes Add references to Parser namespace

Split TdsParserSafeHandles into separate files

ae970dc

Add references to Parser namespace

Split TdsEnums.cs

39563a9

Add references where necessary

Split extra classes from TdsParserStateObject.cs

02f2836

Move TdsParserStateObject and multiplexer partial

2284167

Move is made wholesale to preserve history

Move TdsParser

7356aed

Moved wholesale to retain file history

Move remaining TdsParse clases wholesale

1e1aeef

Move TdsParserStateObjectManaged to Parser namespace

Move Packet and PacketHandle classes to Parser namespace

df3a03c

Move SessionHandle classes to Parser namespace

0a35d51

Remove falsework using statements

7cc5a1b

Login and Tokens namespaces

2bbf4b1

benrr101 force-pushed the dev/russellben/tds-groups branch from d3821a1 to 2bbf4b1 Compare September 11, 2026 16:48

benrr101 added this to the 8.0.0-preview1 milestone Sep 11, 2026

github-actions Bot assigned cheenamalhotra and paulmedynski Sep 11, 2026

Suggestions from @edwardneal

7de1e6a

This creates a stub namespace that native SNI will go into

Copilot AI review requested due to automatic review settings September 11, 2026 18:04

Copilot started reviewing on behalf of benrr101 September 11, 2026 18:05 View session

Copilot AI reviewed Sep 11, 2026

View reviewed changes

Comment thread src/Microsoft.Data.SqlClient/src/Microsoft/Data/SqlClient/Parser/Tokens/_SqlMetaData.cs

using System;

using System.Data;

namespace Microsoft.Data.SqlClient.Parser.Tokens;

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Refactor TDS parser into focused namespaces and files - #4675

Refactor TDS parser into focused namespaces and files#4675
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benrr101 commented Sep 10, 2026

Description

Issues

Testing

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🔵 Needs a closer look

Suppressed comments (3)

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🟡 Changes recommended

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