feat/external anchors and relative ids

[baywet]

related MicrosoftDocs/openapi-docs#167 and #2913

[github-code-quality]

Code Coverage Overview

Languages: C#

C# / code-coverage/dotnet

The overall coverage in the feat/external-anchor... branch remains at 88%, unchanged from the main branch.

Show a code coverage summary of the most impacted files.

File	main beb68f5	feat/external-anchor... f7d87f0	+/-
/home/runner/wo...nApiDocument.cs	89%	89%	0%
/home/runner/wo...ApiWorkspace.cs	89%	92%	+3%

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_{Updated July 03, 2026 14:45 UTC
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[baywet]

@copilot update the performance reports

[Copilot]

@copilot update the performance reports

Done — benchmark reports updated in commit chore(benchmark): update performance reports.

[Copilot]

Pull request overview

This PR extends reference resolution for JSON Schema usage in OpenAPI 3.1/3.2 by supporting external plain-name fragment anchors (#anchor) and by registering $id-based schema identifiers for nested subschemas so they can be targeted by absolute/relative IDs.

Changes:

• Add reader tests for external $anchor fragment resolution and nested $id-based subschema resolution (v3.1 + v3.2).
• Register $anchor and $id identifiers for component schemas and their nested subschemas in OpenApiWorkspace.
• Adjust schema reference URI construction to preserve external plain-name fragments (e.g., OAS-schemas.yaml#address) rather than forcing JSON Pointer fragments.

Reviewed changes

Copilot reviewed 11 out of 12 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
test/Microsoft.OpenApi.Readers.Tests/V32Tests/RelativeReferenceTests.cs	Adds v3.2 regression tests for external $anchor refs and nested $id refs.
test/Microsoft.OpenApi.Readers.Tests/V31Tests/RelativeReferenceTests.cs	Adds v3.1 regression tests for external $anchor refs and nested $id refs.
src/Microsoft.OpenApi/Services/OpenApiWorkspace.cs	Registers $anchor/$id schema identifiers for nested subschemas and resolves non-JSON-pointer fragments via the workspace registry.
src/Microsoft.OpenApi/Models/OpenApiDocument.cs	Preserves external plain-name fragments when constructing schema reference URIs for workspace lookup.
performance/benchmark/BenchmarkDotNet.Artifacts/results/performance.EmptyModels-report.html	Updated benchmark artifact output.
performance/benchmark/BenchmarkDotNet.Artifacts/results/performance.EmptyModels-report.csv	Updated benchmark artifact output.
performance/benchmark/BenchmarkDotNet.Artifacts/results/performance.EmptyModels-report-github.md	Updated benchmark artifact output.
performance/benchmark/BenchmarkDotNet.Artifacts/results/performance.Descriptions-report.json	Updated benchmark artifact output.
performance/benchmark/BenchmarkDotNet.Artifacts/results/performance.Descriptions-report.html	Updated benchmark artifact output.
performance/benchmark/BenchmarkDotNet.Artifacts/results/performance.Descriptions-report.csv	Updated benchmark artifact output.
performance/benchmark/BenchmarkDotNet.Artifacts/results/performance.Descriptions-report-github.md	Updated benchmark artifact output.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
96.1% Coverage on New Code
1.5% Duplication on New Code

See analysis details on SonarQube Cloud

[Copilot]

Pull request overview

Copilot reviewed 12 out of 13 changed files in this pull request and generated no new comments.

[Youssef1313]

I'm not familiar on everything but giving a sign-off (thought the approval won't be counting anyways as I'm not a maintainer in this repo)