From b72d9fa41dc817427c295a073a94b23259d32851 Mon Sep 17 00:00:00 2001
From: JJ Kasper <jj@jjsweb.site>
Date: Tue, 5 May 2020 15:19:07 -0500
Subject: [PATCH] Update tests to poll for output instead of wait for it
 (#12534)

---
 .../jsconfig-baseurl/test/index.test.js       | 12 ++---
 .../jsconfig-paths/test/index.test.js         | 10 +++--
 test/lib/next-test-utils.js                   | 45 ++++++++++---------
 3 files changed, 38 insertions(+), 29 deletions(-)

diff --git a/test/integration/jsconfig-baseurl/test/index.test.js b/test/integration/jsconfig-baseurl/test/index.test.js
index 095bbae983..f451622dba 100644
--- a/test/integration/jsconfig-baseurl/test/index.test.js
+++ b/test/integration/jsconfig-baseurl/test/index.test.js
@@ -8,7 +8,7 @@ import {
   findPort,
   launchApp,
   killApp,
-  waitFor,
+  check,
 } from 'next-test-utils'
 
 jasmine.DEFAULT_TIMEOUT_INTERVAL = 1000 * 60 * 2
@@ -54,11 +54,13 @@ describe('TypeScript Features', () => {
       )
       await renderViaHTTP(appPort, '/hello')
 
-      await waitFor(2 * 1000)
-      await fs.writeFile(basicPage, contents)
-      expect(output).toContain(
-        `Module not found: Can't resolve 'components/worldd' in`
+      const found = await check(
+        () => output,
+        /Module not found: Can't resolve 'components\/worldd' in/,
+        false
       )
+      await fs.writeFile(basicPage, contents)
+      expect(found).toBe(true)
     })
   })
 })
diff --git a/test/integration/jsconfig-paths/test/index.test.js b/test/integration/jsconfig-paths/test/index.test.js
index 9daeb5c2b0..b1393f1a73 100644
--- a/test/integration/jsconfig-paths/test/index.test.js
+++ b/test/integration/jsconfig-paths/test/index.test.js
@@ -8,7 +8,7 @@ import {
   findPort,
   launchApp,
   killApp,
-  waitFor,
+  check,
 } from 'next-test-utils'
 
 jasmine.DEFAULT_TIMEOUT_INTERVAL = 1000 * 60 * 2
@@ -71,9 +71,13 @@ describe('TypeScript Features', () => {
       await fs.writeFile(basicPage, contents.replace('@c/world', '@c/worldd'))
       await renderViaHTTP(appPort, '/basic-alias')
 
-      await waitFor(2 * 1000)
+      const found = await check(
+        () => output,
+        /Module not found: Can't resolve '@c\/worldd' in/,
+        false
+      )
       await fs.writeFile(basicPage, contents)
-      expect(output).toContain(`Module not found: Can't resolve '@c/worldd' in`)
+      expect(found).toBe(true)
     })
   })
 })
diff --git a/test/lib/next-test-utils.js b/test/lib/next-test-utils.js
index dc504e7601..b570b83c2e 100644
--- a/test/lib/next-test-utils.js
+++ b/test/lib/next-test-utils.js
@@ -338,32 +338,35 @@ export async function startCleanStaticServer(dir) {
   return server
 }
 
-export async function check(contentFn, regex) {
-  let found = false
-  const timeout = setTimeout(async () => {
-    if (found) {
-      return
-    }
-    let content
+// check for content in 1 second intervals timing out after
+// 30 seconds
+export async function check(contentFn, regex, hardError = true) {
+  let content
+
+  for (let tries = 0; tries < 30; tries++) {
     try {
       content = await contentFn()
-    } catch (err) {
-      console.error('Error while getting content', { regex })
-    }
-    console.error('TIMED OUT CHECK: ', { regex, content })
-    throw new Error('TIMED OUT: ' + regex + '\n\n' + content)
-  }, 1000 * 30)
-  while (!found) {
-    try {
-      const newContent = await contentFn()
-      if (regex.test(newContent)) {
-        found = true
-        clearTimeout(timeout)
-        break
+      if (regex.test(content)) {
+        // found the content
+        return true
       }
       await waitFor(1000)
-    } catch (ex) {}
+    } catch (err) {
+      if (tries === 30) {
+        console.error('Error while getting content', { regex }, err)
+      }
+    }
   }
+  console.error('TIMED OUT CHECK: ', { regex, content })
+
+  if (hardError) {
+    // maintain previous behavior where the error is thrown in a timeout
+    // and isn't caught when wrapped in a try/catch
+    setTimeout(() => {
+      throw new Error('TIMED OUT: ' + regex + '\n\n' + content)
+    }, 1)
+  }
+  return false
 }
 
 export class File {