fix(core): DataView comparison does not work in toStrictEqual

Author: Dunqing

packages/expect/src/jest-utils.ts

@@ -478,11 +478,16 @@ export function typeEquality(a: any, b: any): boolean | undefined {
 
 export function arrayBufferEquality(a: unknown,
   b: unknown): boolean | undefined {
-  if (!(a instanceof ArrayBuffer) || !(b instanceof ArrayBuffer))
-    return undefined
+  let dataViewA = a as DataView
+  let dataViewB = b as DataView
+
+  if (!(a instanceof DataView && b instanceof DataView)) {
+    if (!(a instanceof ArrayBuffer) || !(b instanceof ArrayBuffer))
+      return undefined
 
-  const dataViewA = new DataView(a)
-  const dataViewB = new DataView(b)
+    dataViewA = new DataView(a)
+    dataViewB = new DataView(b)
+  }
 
   // Buffers are not equal when they do not have the same byte length
   if (dataViewA.byteLength !== dataViewB.byteLength)

test/core/test/jest-expect.test.ts

@@ -466,6 +466,25 @@ describe('.toStrictEqual()', () => {
       Uint8Array.from([9, 3]).buffer,
     )
   })
+
+  it('does not pass for DataView', () => {
+    expect(new DataView(Uint8Array.from([1, 2, 3]).buffer)).not.toStrictEqual(
+      new DataView(Uint8Array.from([3, 2, 1]).buffer),
+    )
+
+    expect(new DataView(Uint16Array.from([1, 2]).buffer)).not.toStrictEqual(
+      new DataView(Uint16Array.from([2, 1]).buffer),
+    )
+  })
+
+  it('passes for matching DataView', () => {
+    expect(new DataView(Uint8Array.from([1, 2, 3]).buffer)).toStrictEqual(
+      new DataView(Uint8Array.from([1, 2, 3]).buffer),
+    )
+    expect(new DataView(Uint8Array.from([]).buffer)).toStrictEqual(
+      new DataView(Uint8Array.from([]).buffer),
+    )
+  })
 })
 
 describe('toBeTypeOf()', () => {