feat: Export snapshot state to expect.extend. (#1378)

examples/image-snapshot/README.md

@@ -0,0 +1,5 @@
+# Vitest Demo
+
+Run `npm test` and change a test or source code to see HMR in action!
+
+Learn more at https://vitest.dev

examples/image-snapshot/package.json

@@ -0,0 +1,21 @@
+{
+  "name": "@vitest/example-image-snapshot",
+  "type": "module",
+  "private": true,
+  "license": "MIT",
+  "main": "index.js",
+  "scripts": {
+    "test": "vitest",
+    "test:ui": "vitest --ui",
+    "test:run": "vitest run"
+  },
+  "devDependencies": {
+    "@vitest/ui": "latest",
+    "jest-image-snapshot": "^4.5.1",
+    "vite": "^2.9.9",
+    "vitest": "latest"
+  },
+  "stackblitz": {
+    "startCommand": "npm run test:ui"
+  }
+}

examples/image-snapshot/test/basic.test.ts

@@ -0,0 +1,17 @@
+import { readFileSync } from 'fs'
+import { expect, test } from 'vitest'
+import { toMatchImageSnapshot } from 'jest-image-snapshot'
+
+declare global {
+  namespace jest {
+    interface Matchers<R> {
+      toMatchImageSnapshot(): R
+    }
+  }
+}
+
+expect.extend({ toMatchImageSnapshot })
+
+test('image snapshot', () => {
+  expect(readFileSync('./test/stubs/input-image.png')).toMatchImageSnapshot()
+})

examples/image-snapshot/vite.config.ts

@@ -0,0 +1,12 @@
+/// <reference types="vitest" />
+
+// Configure Vitest (https://vitest.dev/config/)
+
+import { defineConfig } from 'vite'
+
+export default defineConfig({
+  test: {
+    /* for example, use global to avoid globals imports (describe, test, expect): */
+    // globals: true,
+  },
+})

packages/vitest/src/integrations/chai/jest-extend.ts

@@ -5,6 +5,7 @@ import type {
   MatchersObject,
   SyncExpectationResult,
 } from '../../types/chai'
+import { getSnapshotClient } from '../snapshot/chai'
 import { AsymmetricMatcher } from './jest-asymmetric-matchers'
 import { getState } from './jest-expect'
 
@@ -37,6 +38,7 @@ const getMatcherState = (assertion: Chai.AssertionStatic & Chai.Assertion) => {
     equals,
     // needed for built-in jest-snapshots, but we don't use it
     suppressedErrors: [],
+    snapshotState: getSnapshotClient().snapshotState!,
   }
 
   return {

packages/vitest/src/types/chai.ts

@@ -9,6 +9,7 @@ import type { use as chaiUse } from 'chai'
  */
 
 import type * as jestMatcherUtils from '../integrations/chai/jest-matcher-utils'
+import type SnapshotState from '../integrations/snapshot/port/state'
 
 export type FirstFunctionArgument<T> = T extends (arg: infer A) => unknown ? A : never
 export type ChaiPlugin = FirstFunctionArgument<typeof chaiUse>
@@ -33,6 +34,7 @@ export interface MatcherState {
   isExpectingAssertionsError?: Error | null
   isNot: boolean
   promise: string
+  snapshotState: SnapshotState
   suppressedErrors: Array<Error>
   testPath?: string
   utils: typeof jestMatcherUtils & {