fix: correct error pointer when extension parser throws OpenApiException

[Copilot]

Pull Request

Description

Extension parser exceptions were missing parent path segments in error pointers. For instance, an exception in #/definitions/demo/x-tag would report as #/definitions/x-tag, omitting demo.

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update
• Other (please describe):

Changes Made

• Wrapped extension parser invocations in LoadExtension methods with try-catch blocks across all OpenAPI versions (V2, V3, V3.1, V3.2)
• On OpenApiException, set pointer to current context location before logging to diagnostic
• Return default JsonNodeExtension after logging to allow parsing to continue
• Added test coverage for V2.0, V3.0, and V3.1 scenarios using raw string literals for consistency

Example:

var settings = new OpenApiReaderSettings
{
    ExtensionParsers = { { "x-tag", (any, version) => throw new OpenApiException("Testing") } }
};
var result = OpenApiDocument.Parse(json, "json", settings);

// Before: error.Pointer = "#/definitions/x-tag" (missing "demo")
// After:  error.Pointer = "#/definitions/demo/x-tag" (correct)

Testing

• Unit tests added/updated
• Integration tests added/updated
• Manual testing performed
• All existing tests pass

Checklist

• My code follows the code style of this project
• I have performed a self-review of my own code
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

Versions applicability

• My change applies to the version 1.X of the library, if so PR link:
• My change applies to the version 2.X of the library, if so PR link:
• My change applies to the version 3.X of the library, if so PR link:
• I have evaluated the applicability of my change against the other versions above.

Additional Notes

All LoadExtension implementations now follow a consistent exception handling pattern. The fix preserves parsing continuity by returning a default extension when custom parsers fail. Test code uses raw string literals ("""...""") for multi-line JSON data, consistent with the project's coding style.

Original prompt

---

This section details on the original issue you should resolve

<issue_title>OpenApiError.Pointer skips a level if extension parser throws OpenApiException</issue_title>
<issue_description># To reproduce

Microsoft.OpenApi.Readers 1.2.2

OpenAPI 2.0 document:

{
  "swagger": "2.0",
  "info": {
    "title": "Demo",
    "version": "1"
  },
  "paths": {},
  "definitions": {
    "demo": {
      "x-tag": null
    }
  }
}

Read with an extension parser that throws OpenApiException:

var settings = new OpenApiReaderSettings()
{
    ExtensionParsers =
    {
        { "x-tag", (any, version) => throw new OpenApiException("Testing") },
    },
};
var apiReader = new OpenApiStreamReader(settings);
OpenApiDocument document = apiReader.Read(stream, out OpenApiDiagnostic diagnostic);
Console.Error.WriteLine(diagnostic.Errors[0]);

Expected result

Testing [#/definitions/demo/x-tag]

Actual result

Testing [#/definitions/x-tag]

</issue_description>

<agent_instructions>start from support/v2 and target support/v2 for the pull request.
make sure you start by defining unit tests first.
make sure you consider the details in my response to this issue.
make sure you follow conventional commits conventions.</agent_instructions>

Comments on the Issue (you are @copilot in this section)

@baywet Hi @KalleOlaviNiemitalo Thank you for using the SDK and for reaching out. Thank you for your patience.

This is implemented here (3 other instances)

OpenAPI.NET/src/Microsoft.OpenApi/Reader/V2/OpenApiV2Deserializer.cs

Line 80 in c4f798a

if (node.Context.ExtensionParsers is not null && node.Context.ExtensionParsers.TryGetValue(name, out var parser))

And that's happening because the call to the parser should be surrounded by a try catch, and when an exception is thrown, it should be captured, the pointer amended, and logged as an error in the context with the right pointer.

Additional tests should be added in this file.

OpenAPI.NET/test/Microsoft.OpenApi.Readers.Tests/TestCustomExtension.cs

Line 13 in c4f798a

public void ParseCustomExtension()

I'll assign copilot to get a fix for this in v2 and v3, but we won't be addressing this in v1.

Let us know if you have any additional comments or questions.</comment_new>

• Fixes OpenApiError.Pointer skips a level if extension parser throws OpenApiException #501

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[sonarqubecloud]

Quality Gate failed

Failed conditions
32.0% Duplication on New Code (required ≤ 3%)

See analysis details on SonarQube Cloud