Add global:: qualifier to System namespaces in OptionsValidatorGenerator

[haltandcatchwater]

Note

This contribution was authored with the assistance of AI (Claude Code).

Resolves #118476. Following up on report by @Ternstrom.

Summary

The OptionsValidatorGenerator emitted [System.Diagnostics.CodeAnalysis.UnconditionalSuppressMessage(...)] without the global:: prefix. When the consuming project contains a namespace like XXX.System, the compiler resolves System.Diagnostics against that namespace instead of the global one, causing:

CS0234: The type or namespace name 'Diagnostics' does not exist in the namespace 'XXX.System'

All other attributes in the emitter already use global:: consistently — this was the only one missed.

Changes

• Emitter.cs: Add global:: prefix to the UnconditionalSuppressMessage attribute emission
• 7 baseline files: Updated to match the new generated output

Test Plan

• Existing source generator baseline tests verify the generated output matches (these are exact string comparisons)
• CI validates the fix compiles and all existing tests pass

[rosebyte]

@copilot please invoke the code-review skill and post your analysis/results as a comment on this PR

[Copilot]

Pull request overview

Updates the Microsoft.Extensions.Options source generator output to consistently qualify UnconditionalSuppressMessage with global::, preventing namespace shadowing issues (e.g., consumer-defined XXX.System) that can break compilation.

Changes:

• Emit [global::System.Diagnostics.CodeAnalysis.UnconditionalSuppressMessage(...)] in OptionsValidatorGenerator output.
• Update generator baseline .g.cs files to reflect the new emitted attribute text.

Reviewed changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
src/libraries/Microsoft.Extensions.Options/gen/Emitter.cs	Adds global:: qualifier when emitting UnconditionalSuppressMessage to avoid ambiguous System namespace resolution in consuming projects.
src/libraries/Microsoft.Extensions.Options/tests/SourceGenerationTests/Baselines/NetCoreApp/Validators.g.cs	Updates baseline output to match the new globally-qualified attribute emission.
src/libraries/Microsoft.Extensions.Options/tests/SourceGeneration.Unit.Tests/Baselines/UsingInterfaceAsPropertyTypeForLengthAttributesTests.netcore.g.cs	Baseline update for globally-qualified UnconditionalSuppressMessage.
src/libraries/Microsoft.Extensions.Options/tests/SourceGeneration.Unit.Tests/Baselines/OptionsExtendingSystemClassTest.netcore.g.cs	Baseline update for globally-qualified UnconditionalSuppressMessage.
src/libraries/Microsoft.Extensions.Options/tests/SourceGeneration.Unit.Tests/Baselines/GeneratedAttributesTest.netcore.lang11.g.cs	Baseline update for globally-qualified UnconditionalSuppressMessage.
src/libraries/Microsoft.Extensions.Options/tests/SourceGeneration.Unit.Tests/Baselines/GeneratedAttributesTest.netcore.lang10.g.cs	Baseline update for globally-qualified UnconditionalSuppressMessage.
src/libraries/Microsoft.Extensions.Options/tests/SourceGeneration.Unit.Tests/Baselines/EmitterWithCustomValidator.netcore.g.cs	Baseline update for globally-qualified UnconditionalSuppressMessage.
src/libraries/Microsoft.Extensions.Options/tests/SourceGeneration.Unit.Tests/Baselines/DataAnnotationAttributesWithParams.g.cs	Baseline update for globally-qualified UnconditionalSuppressMessage.

[svick]

I have added the global:: prefix to more places in this source generator where they were missing.