Fix SSR error handling in the global scope (#3877)

* Fix SSR error handling.

* Remove unwanted console.logs

* Fix a typo.

* Fix current tests.

* Add a new test case for this case.

* Error should only be logged if it is not a 404

server/require.js

@@ -55,9 +55,17 @@ export function getPagePath (page, {dir, dist}) {
 
 export default function requirePage (page, {dir, dist}) {
   const pagePath = getPagePath(page, {dir, dist})
+
   try {
     return require(pagePath)
   } catch (err) {
+    if (err.code === 'MODULE_NOT_FOUND') {
       throw pageNotFoundError(page)
     }
+    console.error(err)
+    // If this is not a MODULE_NOT_FOUND error,
+    // it should be something with the content of the page.
+    // So, Next.js rendering system will catch it and process.
+    throw err
+  }
 }

test/integration/basic/pages/error-in-the-global-scope.js

@@ -0,0 +1,5 @@
+aa = 10 //eslint-disable-line
+
+export default () => (
+  <div>Hello</div>
+)

test/integration/basic/test/rendering.js

@@ -96,11 +96,16 @@ export default function ({ app }, suiteName, render, fetch) {
       expect(pre.text()).toMatch(/The default export is not a React Component/)
     })
 
-    test('error', async () => {
-      const $ = await get$('/error')
+    test('error-inside-page', async () => {
+      const $ = await get$('/error-inside-page')
       expect($('pre').text()).toMatch(/This is an expected error/)
     })
 
+    test('error-in-the-global-scope', async () => {
+      const $ = await get$('/error-in-the-global-scope')
+      expect($('pre').text()).toMatch(/aa is not defined/)
+    })
+
     test('asPath', async () => {
       const $ = await get$('/nav/as-path', { aa: 10 })
       expect($('.as-path-content').text()).toBe('/nav/as-path?aa=10')