test: add cypress test for TS

Author: cexbrayat

packages/@vue/cli-plugin-e2e-cypress/__tests__/cypressPlugin.spec.js

@@ -27,3 +27,29 @@ test('should work', async () => {
     await project.run(`vue-cli-service test:e2e --headless`)
   }
 })
+
+test('should work with TS', async () => {
+  const project = await create('e2e-cypress-ts', {
+    plugins: {
+      '@vue/cli-plugin-typescript': {
+        'classComponent': true,
+        'tsLint': true,
+        'lintOn': ['save']
+      },
+      '@vue/cli-plugin-e2e-cypress': {}
+    }
+  })
+
+  const pkg = JSON.parse(await project.read('package.json'))
+  expect(pkg.devDependencies).toHaveProperty('@cypress/webpack-preprocessor')
+
+  const config = JSON.parse(await project.read('cypress.json'))
+  config.video = false
+  await project.write('cypress.json', JSON.stringify(config))
+
+  if (!process.env.CI) {
+    await project.run(`vue-cli-service test:e2e`)
+  } else if (!process.env.APPVEYOR) {
+    await project.run(`vue-cli-service test:e2e --headless`)
+  }
+})