fix(dereference): modification for circular ref for delete objects (#132)

* fix(dereference): modification for circular ref

* fix(dereference): added comments

* fix: update test cases for circular objects

* fix: update variable name

Author: SB-rohitdesai

src/__tests__/decycle.spec.ts

@@ -105,7 +105,7 @@ describe('decycle', () => {
     });
   });
 
-  it('should not create refs for objects that are not circular', () => {
+  it('should create refs circular objects and repeated values', () => {
     const obj2 = {
       circle: {},
     };
@@ -131,7 +131,7 @@ describe('decycle', () => {
         foo: 'bar',
       },
       obj3B: {
-        foo: 'bar',
+        $ref: '#/obj3A',
       },
       paths: {
         '/circle': {

src/decycle.ts

@@ -1,36 +1,46 @@
 import { isPlainObject } from './isPlainObject';
 import { pathToPointer } from './pathToPointer';
 
-export const decycle = (obj: unknown, replacer?: (value: any) => any) => {
+export function decycle(obj: unknown, replacer?: (value: any) => any) {
   const objs = new WeakMap<object, string>();
-  return (function derez(value: any, path: string[]) {
-    // The new object or array
-    let curObj: any;
-
-    // If a replacer function was provided, then call it to get a replacement value.
-    if (replacer) value = replacer(value);
+  const objectsToBeDeleted: object[] = []; // To keep track of objects to delete later
 
+  function derez(value: any, path: (string | number)[]): any {
+    if (replacer) {
+      value = replacer(value);
+    }
     if (isPlainObject(value) || Array.isArray(value)) {
-      // The path of an earlier occurance of value
       const oldPath = objs.get(value);
+
       // If the value is an object or array, look to see if we have already
       // encountered it. If so, return a {"$ref":PATH} object.
-      if (oldPath) return { $ref: oldPath };
-
+      if (oldPath) {
+        return { $ref: oldPath };
+      }
       objs.set(value, pathToPointer(path));
       // If it is an array, replicate the array.
       if (Array.isArray(value)) {
-        curObj = value.map((element, i) => derez(element, [...path, String(i)]));
-      } else {
-        // It is an object, replicate the object.
-        curObj = {};
-        Object.keys(value).forEach(name => {
-          curObj[name] = derez(value[name], [...path, name]);
-        });
+        return value.map((element, i) => derez(element, [...path, i]));
       }
-      objs.delete(value);
-      return curObj;
+      const newObj: Record<string, any> = {};
+      for (const name in value) {
+        if (Object.prototype.hasOwnProperty.call(value, name)) {
+          newObj[name] = derez(value[name], [...path, name]);
+        }
+      }
+      // Schedule object for deletion after derez completes
+      objectsToBeDeleted.push(value);
+      return newObj;
     }
     return value;
-  })(obj, []);
-};
+  }
+
+  const result = derez(obj, []);
+
+  // Clean up objs for objects that were processed
+  objectsToBeDeleted.forEach(obj => {
+    objs.delete(obj);
+  });
+
+  return result;
+}