Use deterministic ordering for C# derived-model references

[Copilot]

Derived-model references in C# documentation inherit HashSet enumeration order, risking unintended changes on regeneration.

• Ordering: Sort the deduplicated models by name using StringComparer.Ordinal for culture-independent output.
• Coverage: Add regression cases for reversed input order, deduplication, and ordinal sorting; update abstract and non-abstract base-model documentation expectations.

• Fixes Use deterministic ordering in abstract models reference docs #8441

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[Copilot]

🔵 Needs a closer look

Add a fully qualified-name tie-breaker for same-named models to ensure ordering is deterministic.

Pull request overview

Updates C# derived-model documentation to use deterministic ordering and adds regression coverage.

Changes:

• Sorts derived models with ordinal comparison.
• Adds ordering and deduplication tests.
• Updates documentation expectations.

File summaries

File	Reviewed change
packages/http-client-csharp/generator/Microsoft.TypeSpec.Generator/test/Providers/ModelProviders/ModelProviderTests.cs	Adds ordering and deduplication coverage.
packages/http-client-csharp/generator/Microsoft.TypeSpec.Generator/test/Providers/ModelProviders/DiscriminatorTests.cs	Updates documentation expectations.
packages/http-client-csharp/generator/Microsoft.TypeSpec.Generator/src/Providers/ModelProvider.cs	Applies deterministic derived-model sorting.

Review details

Suppressed comments (1)

packages/http-client-csharp/generator/Microsoft.TypeSpec.Generator/src/Providers/ModelProvider.cs:134

• This only orders by the simple generated name, so two valid derived models with the same name in different namespaces compare equal. OrderBy preserves the HashSet order for equal keys, leaving the fully qualified <see> references nondeterministic; add a ThenBy on m.Type.FullyQualifiedName (the value emitted in the documentation).

            return [.. derivedModels.OrderBy(m => m.Name, StringComparer.Ordinal)];

• Files reviewed: 3/3 changed files
• Comments generated: 0
• Review effort level: Lite

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[JoshLove-msft]

Copilot you need to regenerate

[Copilot]

Copilot you need to regenerate

Regenerated all C# libraries in 510e491. Three generated sample files changed, and repeat generation produced identical output. The build and all runnable emitter/.NET tests passed.

[Copilot]

🔵 Needs a closer look

One or more issues must be addressed before approval.

Review details

Suppressed comments (1)

packages/http-client-csharp/generator/Microsoft.TypeSpec.Generator/src/Providers/ModelProvider.cs:134

• Sorting only by the short Name does not make this fully deterministic: derived models can share a C# name when they come from different namespaces, while the documentation emits Type.FullyQualifiedName. For equal names, OrderBy preserves the HashSet iteration order, so reversed input can still reorder the references; add an ordinal tie-breaker on the fully qualified name (and cover that case).

            return [.. derivedModels.OrderBy(m => m.Name, StringComparer.Ordinal)];

• Files reviewed: 3/6 changed files
• Comments generated: 0 new
• Review effort level: Lite