fix: do not overwrite in circular self references

lib/__tests__/bundle.test.ts

@@ -9,7 +9,17 @@ describe("bundle", () => {
     const refParser = new $RefParser();
     const pathOrUrlOrSchema = path.resolve("lib", "__tests__", "spec", "circular-ref-with-description.json");
     const schema = await refParser.bundle({ pathOrUrlOrSchema });
-    expect(schema).not.toBeUndefined();
+    expect(schema).toEqual({
+      schemas: {
+        Bar: {
+          $ref: '#/schemas/Foo',
+          description: 'ok',
+        },
+        Foo: {
+          $ref: '#/schemas/Bar',
+        },
+      },
+    });
   });
 
   it("bundles multiple references to the same file correctly", async () => {

lib/__tests__/pointer.test.ts

@@ -7,7 +7,6 @@ describe("pointer", () => {
     const refParser = new $RefParser();
     const pathOrUrlOrSchema = path.resolve("lib", "__tests__", "spec", "openapi-paths-ref.json");
     const schema = (await refParser.bundle({ pathOrUrlOrSchema })) as any;
-    console.log(JSON.stringify(schema, null, 2));
 
     // The GET endpoint should have its schema defined inline
     const getSchema = schema.paths["/foo"].get.responses["200"].content["application/json"].schema;

lib/bundle.ts

@@ -579,9 +579,11 @@ function remap(parser: $RefParser, inventory: InventoryEntry[]) {
       continue;
     }
 
-    // Keep internal refs internal
+    // Keep internal refs internal. However, if the $ref extends the resolved value
+    // (i.e. it has additional properties in addition to "$ref"), then we must
+    // preserve the original $ref rather than rewriting it to the resolved hash.
     if (!entry.external) {
-      if (entry.$ref && typeof entry.$ref === "object") {
+      if (!entry.extended && entry.$ref && typeof entry.$ref === "object") {
         entry.$ref.$ref = entry.hash;
       }
       continue;