Merge branch 'fe-use-process-timer-in-jest-timeout' into 'master'

Use process timer for jest timeout testing

See merge request gitlab-org/gitlab-ce!28209

spec/frontend/helpers/timeout.js

-let testTimeoutInMs;
+const NS_PER_SEC = 1e9;
+const NS_PER_MS = 1e6;
 
-export const setTestTimeout = newTimeoutInMs => {
-  testTimeoutInMs = newTimeoutInMs;
-  jest.setTimeout(newTimeoutInMs);
+let testTimeoutNS;
+
+export const setTestTimeout = newTimeoutMS => {
+  testTimeoutNS = newTimeoutMS * NS_PER_MS;
+  jest.setTimeout(newTimeoutMS);
 };
 
-export const initializeTestTimeout = defaultTimeoutInMs => {
-  setTestTimeout(defaultTimeoutInMs);
+export const initializeTestTimeout = defaultTimeoutMS => {
+  setTestTimeout(defaultTimeoutMS);
 
   let testStartTime;
 
   // https://github.com/facebook/jest/issues/6947
   beforeEach(() => {
-    testStartTime = Date.now();
+    testStartTime = process.hrtime();
   });
 
   afterEach(() => {
-    const elapsedTimeInMs = Date.now() - testStartTime;
-    if (elapsedTimeInMs > testTimeoutInMs) {
-      throw new Error(`Test took too long (${elapsedTimeInMs}ms > ${testTimeoutInMs}ms)!`);
+    const [seconds, remainingNs] = process.hrtime(testStartTime);
+    const elapsedNS = seconds * NS_PER_SEC + remainingNs;
+
+    if (elapsedNS > testTimeoutNS) {
+      throw new Error(
+        `Test took too long (${elapsedNS / NS_PER_MS}ms > ${testTimeoutNS / NS_PER_MS}ms)!`,
+      );
     }
   });
 };