False positive circular-reference-invalid on external $ref schemas since v1.709.2

[SaranshChaudhary]

Description

speakeasy lint openapi incorrectly reports non-terminating circular references when validating an OpenAPI 3.1 spec that uses external $refs to split schema files. The referenced schemas do not form any cycles.

Regression

• Last passing: v1.709.1
• First failing: v1.709.2 (commit 498f86a)

Error output

ERROR  validation error: [line 107:7] circular-reference-invalid - non-terminating circular reference
       detected: components/schemas/Product.json -> components/schemas/Product.json
ERROR  validation error: [line 120:7] circular-reference-invalid - non-terminating circular reference
       detected: components/schemas/Product.json -> components/schemas/Product.json
ERROR  validation error: [line 144:7] circular-reference-invalid - non-terminating circular reference
       detected: components/schemas/Product.json -> components/schemas/Product.json

Reproduction

The spec uses a split-file structure where a parent schema (Product.json) references child schemas via external $refs:

Product.json
  ├── pricing:      $ref: ./ProductPricing.json       (terminal — no further $refs)
  ├── promotion:    $ref: ./ProductPromotion.json      ($refs only promotion-type schemas, all terminal)
  ├── bundle_items: $ref: ./ProductBundleItem.json     ($refs Item.json → various terminal schemas)
  ├── variants:     $ref: ./Variant.json               (terminal)
  ├── images:       $ref: ./ProductImage.json           (terminal)
  └── attributes:   $ref: ./ProductAttribute.json       ($refs attribute-type schemas, all terminal)

A full graph traversal confirms no schema references back to Product.json. The Product.json -> Product.json cycle reported by the linter does not exist.

Command

speakeasy lint openapi --logLevel warn --non-interactive --schema catalog.json

where catalog.json is an OpenAPI 3.1 spec referencing schemas in ./components/schemas/ via external $refs like {"$ref": "./components/schemas/Product.json"}.

Expected behavior

Lint should pass (or warn), as there are no circular references in the $ref graph.

Environment

• OS: macOS (darwin arm64)
• Speakeasy CLI: fails on v1.709.2+, passes on v1.709.1