Add test cases for getInitialProps based redirect logic. (#1578)

With that, we are making sure we don't break this
functionality in the future.

test/integration/basic/pages/nav/index.js

@@ -27,6 +27,7 @@ export default class extends Component {
         <Link href='/empty-get-initial-props'><a id='empty-props' style={linkStyle}>Empty Props</a></Link>
         <Link href='/nav/self-reload'><a id='self-reload-link' style={linkStyle}>Self Reload</a></Link>
         <Link href='/nav/shallow-routing'><a id='shallow-routing-link' style={linkStyle}>Shallow Routing</a></Link>
+        <Link href='/nav/redirect'><a id='redirect-link' style={linkStyle}>Redirect</a></Link>
         <Link
           href={{ pathname: '/nav/querystring', query: { id: 10 } }}
           as={{ pathname: '/nav/querystring/10', hash: '10' }}

test/integration/basic/pages/nav/redirect.js

@@ -0,0 +1,18 @@
+import Router from 'next/router'
+
+const Page = () => (
+  <p>This is the page</p>
+)
+
+Page.getInitialProps = (ctx) => {
+  if (ctx.res) {
+    ctx.res.writeHead(302, { Location: '/nav/about' })
+    ctx.res.end()
+  } else {
+    Router.push('/nav/about')
+  }
+
+  return {}
+}
+
+export default Page

test/integration/basic/test/client-navigation.js

@@ -298,5 +298,28 @@ export default (context, render) => {
         browser.close()
       })
     })
+
+    describe('with getInitialProp redirect', () => {
+      it('should redirect the page via client side', async () => {
+        const browser = await webdriver(context.appPort, '/nav')
+        const text = await browser
+          .elementByCss('#redirect-link').click()
+          .waitForElementByCss('.nav-about')
+          .elementByCss('p').text()
+
+        expect(text).toBe('This is the about page.')
+        browser.close()
+      })
+
+      it('should redirect the page when loading', async () => {
+        const browser = await webdriver(context.appPort, '/nav/redirect')
+        const text = await browser
+          .waitForElementByCss('.nav-about')
+          .elementByCss('p').text()
+
+        expect(text).toBe('This is the about page.')
+        browser.close()
+      })
+    })
   })
 }

test/integration/basic/test/index.test.js

@@ -48,7 +48,8 @@ describe('Basic Features', () => {
       renderViaHTTP(context.appPort, '/nav/querystring'),
       renderViaHTTP(context.appPort, '/nav/self-reload'),
       renderViaHTTP(context.appPort, '/nav/hash-changes'),
-      renderViaHTTP(context.appPort, '/nav/shallow-routing')
+      renderViaHTTP(context.appPort, '/nav/shallow-routing'),
+      renderViaHTTP(context.appPort, '/nav/redirect')
     ])
   })
   afterAll(() => stopApp(context.server))