fix: resolve circular ref when cloning object (#1444)

packages/vitest/src/runtime/error.ts

@@ -1,7 +1,7 @@
 import { format } from 'util'
 import { util } from 'chai'
 import { stringify } from '../integrations/chai/jest-matcher-utils'
-import { clone, getType } from '../utils'
+import { deepClone, getType } from '../utils'
 
 const OBJECT_PROTO = Object.getPrototypeOf({})
 
@@ -63,8 +63,8 @@ export function processError(err: any) {
   if (err.name)
     err.nameStr = String(err.name)
 
-  const clonedActual = clone(err.actual)
-  const clonedExpected = clone(err.expected)
+  const clonedActual = deepClone(err.actual)
+  const clonedExpected = deepClone(err.expected)
 
   const { replacedActual, replacedExpected } = replaceAsymmetricMatcher(clonedActual, clonedExpected)
 
@@ -105,9 +105,13 @@ function isReplaceable(obj1: any, obj2: any) {
   return obj1Type === obj2Type && obj1Type === 'Object'
 }
 
-export function replaceAsymmetricMatcher(actual: any, expected: any) {
+export function replaceAsymmetricMatcher(actual: any, expected: any, actualReplaced = new WeakMap(), expectedReplaced = new WeakMap()) {
   if (!isReplaceable(actual, expected))
     return { replacedActual: actual, replacedExpected: expected }
+  if (actualReplaced.has(actual) || expectedReplaced.has(expected))
+    return { replacedActual: actual, replacedExpected: expected }
+  actualReplaced.set(actual, true)
+  expectedReplaced.set(expected, true)
   util.getOwnEnumerableProperties(expected).forEach((key) => {
     const expectedValue = expected[key]
     const actualValue = actual[key]
@@ -123,6 +127,8 @@ export function replaceAsymmetricMatcher(actual: any, expected: any) {
       const replaced = replaceAsymmetricMatcher(
         actualValue,
         expectedValue,
+        actualReplaced,
+        expectedReplaced,
       )
       actual[key] = replaced.replacedActual
       expected[key] = replaced.replacedExpected

packages/vitest/src/utils/base.ts

@@ -51,25 +51,30 @@ function getOwnProperties(obj: any) {
   return Array.from(ownProps)
 }
 
-export function clone<T>(val: T): T {
-  let k: any, out: any, tmp: any
+export function deepClone<T>(val: T): T {
+  const seen = new WeakMap()
+  return clone(val, seen)
+}
 
+export function clone<T>(val: T, seen: WeakMap<any, any>): T {
+  let k: any, out: any
+  if (seen.has(val))
+    return seen.get(val)
   if (Array.isArray(val)) {
     out = Array(k = val.length)
+    seen.set(val, out)
     while (k--)
-      // eslint-disable-next-line no-cond-assign
-      out[k] = (tmp = val[k]) && typeof tmp === 'object' ? clone(tmp) : tmp
+      out[k] = clone(val[k], seen)
     return out as any
   }
 
   if (Object.prototype.toString.call(val) === '[object Object]') {
     out = Object.create(Object.getPrototypeOf(val))
+    seen.set(val, out)
     // we don't need properties from prototype
     const props = getOwnProperties(val)
-    for (const k of props) {
-      // eslint-disable-next-line no-cond-assign
-      out[k] = (tmp = (val as any)[k]) && typeof tmp === 'object' ? clone(tmp) : tmp
-    }
+    for (const k of props)
+      out[k] = clone((val as any)[k], seen)
     return out
   }
 

test/core/test/replace-matcher.test.ts

@@ -45,5 +45,8 @@ describe('replace asymmetric matcher', () => {
       str: expect.any(String),
       arr: [1, expect.anything()],
     })
+    const circleObj: any = { name: 'circle', ref: null }
+    circleObj.ref = circleObj
+    expectReplaceAsymmetricMatcher(circleObj, circleObj)
   })
 })

test/core/test/utils.spec.ts

@@ -1,5 +1,5 @@
 import { describe, expect, test } from 'vitest'
-import { assertTypes, clone, deepMerge, toArray } from '../../../packages/vitest/src/utils'
+import { assertTypes, deepClone, deepMerge, toArray } from '../../../packages/vitest/src/utils'
 import { deepMergeSnapshot } from '../../../packages/vitest/src/integrations/snapshot/port/utils'
 
 describe('assertTypes', () => {
@@ -122,25 +122,28 @@ describe('toArray', () => {
   })
 })
 
-describe('clone', () => {
+describe('deepClone', () => {
   test('various types should be cloned correctly', () => {
-    expect(clone(1)).toBe(1)
-    expect(clone(true)).toBe(true)
-    expect(clone(undefined)).toBe(undefined)
-    expect(clone(null)).toBe(null)
-    expect(clone({ a: 1 })).toEqual({ a: 1 })
-    expect(clone([1, 2])).toEqual([1, 2])
+    expect(deepClone(1)).toBe(1)
+    expect(deepClone(true)).toBe(true)
+    expect(deepClone(undefined)).toBe(undefined)
+    expect(deepClone(null)).toBe(null)
+    expect(deepClone({ a: 1 })).toEqual({ a: 1 })
+    expect(deepClone([1, 2])).toEqual([1, 2])
     const symbolA = Symbol('a')
-    expect(clone(symbolA)).toBe(symbolA)
+    expect(deepClone(symbolA)).toBe(symbolA)
     const objB: any = {}
     Object.defineProperty(objB, 'value', {
       configurable: false,
       enumerable: false,
       value: 1,
       writable: false,
     })
-    expect(clone(objB).value).toEqual(objB.value)
+    expect(deepClone(objB).value).toEqual(objB.value)
     const objC = Object.create(objB)
-    expect(clone(objC).value).toEqual(objC.value)
+    expect(deepClone(objC).value).toEqual(objC.value)
+    const objD: any = { name: 'd', ref: null }
+    objD.ref = objD
+    expect(deepClone(objD)).toEqual(objD)
   })
 })