fix: support original Jest matchers

Fixes #17

packages/expect-puppeteer/src/index.js

@@ -88,7 +88,18 @@ if (typeof global.expect !== 'undefined') {
   const originalExpect = global.expect
   global.expect = (actual, ...args) => {
     const type = getPuppeteerType(actual)
-    if (type) return expectPuppeteer(actual)
+    if (type) {
+      const matchers = expectPuppeteer(actual)
+      const jestMatchers = originalExpect(actual, ...args)
+      return {
+        ...jestMatchers,
+        ...matchers,
+        not: {
+          ...jestMatchers.not,
+          ...matchers.not,
+        },
+      }
+    }
     return originalExpect(actual, ...args)
   }
   Object.keys(originalExpect).forEach(prop => {

packages/expect-puppeteer/src/index.test.js

@@ -0,0 +1,14 @@
+describe('expect-puppeteer', () => {
+  beforeEach(async () => {
+    await page.goto('http://localhost:4444')
+  })
+
+  it('should work with original Jest matchers', async () => {
+    expect(page).toBeDefined()
+    expect(page).not.toBe(null)
+
+    const main = await page.$('main')
+    expect(main).toBeDefined()
+    expect(main).not.toBe(null)
+  })
+})