ref: Create crossPlatformPerformance layer with better typings and fallback for edge-cases

Author: kamilogorek

CHANGELOG.md

@@ -2,7 +2,10 @@
 
 ## Unreleased
 
-- none
+- [core] ref: Remove unused `sentry_timestamp` header (#2458)
+- [node] ref: Drop Node v6, add Node v12 to test matrix, move all scripts to Node v12 (#2455)
+- [apm] fix: Use monotonic clock to compute durations (#2441)
+- [utils] ref: Prevent instantiating unnecessary Date objects in `timestampWithMs` (#2442)
 
 ## 5.12.5
 

packages/apm/src/span.ts

@@ -13,14 +13,18 @@ import {
   uuid4,
 } from '@sentry/utils';
 
-const global = getGlobalObject<Window>();
-
-const performanceNow = (() => {
+const crossPlatformPerformance: Pick<Performance, 'now'> = (() => {
   if (isNodeEnv()) {
-    const { performance } = dynamicRequire(module, 'perf_hooks');
-    return performance.now;
+    const { performance } = dynamicRequire(module, 'perf_hooks') as { performance: Performance };
+    return performance;
   }
-  return global.performance.now.bind(global.performance);
+  return (
+    getGlobalObject<Window>().performance || {
+      now(): number {
+        return Date.now();
+      },
+    }
+  );
 })();
 
 // TODO: Should this be exported?
@@ -109,7 +113,7 @@ export class Span implements SpanInterface, SpanContext {
    * Works with Node.js v8.5.0 or higher.
    * https://nodejs.org/api/perf_hooks.html#perf_hooks_performance_now
    */
-  private readonly _startTimestampMonotonic: number = performanceNow();
+  private readonly _startTimestampMonotonic: number = crossPlatformPerformance.now();
 
   /**
    * Finish timestamp of the span.
@@ -291,7 +295,7 @@ export class Span implements SpanInterface, SpanContext {
       return undefined;
     }
 
-    const durationSeconds = (performanceNow() - this._startTimestampMonotonic) / 1000;
+    const durationSeconds = (crossPlatformPerformance.now() - this._startTimestampMonotonic) / 1000;
     this.timestamp = this.startTimestamp + durationSeconds;
 
     if (this.spanRecorder === undefined) {

packages/node/test/transports/http.test.ts

@@ -97,8 +97,6 @@ describe('HTTPTransport', () => {
     const now = Date.now();
     const mock = jest
       .spyOn(Date, 'now')
-      // Initialize _disabledUntil attribute
-      .mockReturnValueOnce(now)
       // Check for first event
       .mockReturnValueOnce(now)
       // Setting disabledUntil

packages/node/test/transports/https.test.ts

@@ -103,8 +103,6 @@ describe('HTTPSTransport', () => {
     const now = Date.now();
     const mock = jest
       .spyOn(Date, 'now')
-      // Initialize _disabledUntil attribute
-      .mockReturnValueOnce(now)
       // Check for first event
       .mockReturnValueOnce(now)
       // Setting disabledUntil