Fix OpenAPI3 component response conversion to emit reusable response models - #11735

Previously missed (1) — in code that hasn't changed since the last review.

packages/openapi3/src/cli/actions/convert/transforms/transforms.ts:321

• responses is assigned but never used. With noUnusedLocals/linting enabled this will fail the build; even without it, this local can be removed without changing behavior.

  const responses = context.openApi3Doc.components?.responses;
  if (!responses) return;

Previously missed (1) — in code that hasn't changed since the last review.

packages/openapi3/src/cli/actions/convert/transforms/transforms.ts:321

• transformComponentResponses declares responses but never uses it. This adds dead code and makes it harder to see what the function actually depends on.

You can inline the existence check against context.openApi3Doc.components?.responses and remove the unused local.

  const responses = context.openApi3Doc.components?.responses;
  if (!responses) return;

packages/openapi3/src/cli/actions/convert/transforms/transforms.ts:389

• getResponseProperties takes statusCode: string, but then passes it to convertStatusCodeToProperty, which expects Exclude<StatusCodes, "default">. This is a TypeScript type error (a plain string isn’t assignable to StatusCodes) and can break the build.

Consider typing getResponseProperties to StatusCodes (via a type query) and casting the iterated statusCode when calling it, since Object.entries(...) loses the literal key type.

function getResponseProperties(
  statusCode: string,
  response: OpenAPI3Response,
  context: Context,
): TypeSpecModelProperty[] {

Previously missed (1) — in code that hasn't changed since the last review.

packages/openapi3/src/cli/actions/convert/generators/generate-response-expressions.ts:48

• The early return for #/components/responses/... refs bypasses the existing OpenAPI 3.2 SSE (text/event-stream + itemSchema) handling later in generateResponseExpressions, so SSE component responses would incorrectly return the generated response model instead of SSEStream<...>.

  if ("$ref" in props.response && props.response.$ref.startsWith("#/components/responses/")) {
    const componentResponseName = context.getComponentResponseName(props.response.$ref, statusCode);
    if (componentResponseName) {
      return [componentResponseName];
    }

packages/openapi3/test/tsp-openapi3/convert-openapi3-doc.test.ts:285

• This assertion hard-codes an exact newline + indentation sequence ("@error\n model ..."), which is brittle across formatting changes. Prefer a whitespace-tolerant regex so the test only cares that @error is applied to the model.

    strictEqual(
      tsp.includes("@error\n  model RejectedDefault"),
      true,
      "Expected default response model to be marked as an error: " + tsp,
    );