Support performance.measure+mark

RELEASE.md

@@ -8,13 +8,7 @@ You'll need a working installation of [git-extras](https://github.com/tj/git-ext
 $ npm version x.y.z # or npm version [patch|minor|major]
 ```
 
-Runs the tests, builds a changelog and the authors file, updates package.json, creates a new tag and pushes the tag and its commits to the sinon repo.
-
-## Publish to NPM
-
-```
-$ npm publish
-```
+Runs the tests, builds a changelog and the authors file, updates package.json, creates a new tag and pushes the tag and its commits to the sinon repo, as well as publishing.
 
 ## Create a GitHub release
 

src/fake-timers-src.js

@@ -24,7 +24,7 @@
 /**
  * Queues a function to be called during a browser's idle periods
  * @callback RequestIdleCallback
  * @param {function(IdleDeadline)} callback
  * @param {{timeout: number}} options - an options object
  * @returns {number} the id
  */
@@ -51,13 +51,13 @@
 
 /**
  * @typedef RequestAnimationFrame
  * @property {function(number):void} requestAnimationFrame
  * @returns {number} - the id
  */
 
 /**
  * @typedef Performance
  * @property {function(): number} now
  */
 
 /* eslint-disable jsdoc/require-property-description */
@@ -217,6 +217,25 @@
     }
     isPresent.Date = true;
 
+    /**
+     * The PerformanceEntry object encapsulates a single performance metric
+     * that is part of the browser's performance timeline.
+     *
+     * This is an object returned by the `mark` and `measure` methods on the Performance prototype
+     */
+    class FakePerformanceEntry {
+        constructor(name, entryType, startTime, duration) {
+            this.name = name;
+            this.entryType = entryType;
+            this.startTime = startTime;
+            this.duration = duration;
+        }
+
+        toJSON() {
+            return JSON.stringify({ ...this });
+        }
+    }
+
     /**
      * @param {number} num
      * @returns {boolean}
@@ -329,7 +348,7 @@
         return timer && timer.callAt >= from && timer.callAt <= to;
     }
 
     /**
      * @param {Clock} clock
      * @param {Timer} job
      */
@@ -409,7 +428,7 @@
              * @param {number} minute
              * @param {number} second
              * @param {number} ms
              * @returns void
              */
             // eslint-disable-next-line no-unused-vars
             constructor(year, month, date, hour, minute, second, ms) {
@@ -441,7 +460,7 @@
         /**
          * A normal Class constructor cannot be called without `new`, but Date can, so we need
          * to wrap it in a Proxy in order to ensure this functionality of Date is kept intact
          * @type {ClockDate}
          */
         const ClockDateProxy = new Proxy(ClockDate, {
             // handler for [[Call]] invocations (i.e. not using `new`)
@@ -637,7 +656,7 @@
     }
 
     /* eslint consistent-return: "off" */
     /**
      * Timer comparitor
      * @param {Timer} a
      * @param {Timer} b
@@ -768,7 +787,7 @@
         }
     }
 
     /**
      * Gets clear handler name for a given timer type
      * @param {string} ttype
      */
@@ -779,7 +798,7 @@
         return `clear${ttype}`;
     }
 
     /**
      * Gets schedule handler name for a given timer type
      * @param {string} ttype
      */
@@ -790,7 +809,7 @@
         return `set${ttype}`;
     }
 
     /**
      * Creates an anonymous function to warn only once
      */
     function createWarnOnce() {
@@ -1794,6 +1813,11 @@
                                 : NOOP;
                     }
                 });
+                // ensure `mark` returns a value that is valid
+                clock.performance.mark = (name) =>
+                    new FakePerformanceEntry(name, "mark", 0, 0);
+                clock.performance.measure = (name) =>
+                    new FakePerformanceEntry(name, "measure", 0, 100);
             } else if ((config.toFake || []).includes("performance")) {
                 return handleMissingTimer("performance");
             }

test/fake-timers-test.js

@@ -3632,6 +3632,27 @@ describe("FakeTimers", function () {
                 this.clock.uninstall();
             });
 
+            it("should create fake versions of `mark` and `measure` that return PerformanceEntry objects", function () {
+                if (typeof Performance === "undefined") {
+                    return this.skip();
+                }
+
+                function testEntry(performanceEntry) {
+                    assert.keys(performanceEntry, [
+                        "startTime",
+                        "duration",
+                        "name",
+                        "entryType",
+                    ]);
+
+                    assert(typeof performanceEntry.toJSON() === "string");
+                }
+
+                this.clock = FakeTimers.install();
+                testEntry(performance.mark("foo"));
+                testEntry(performance.measure("bar", "s", "t"));
+            });
+
             it("should replace the getEntries, getEntriesByX methods with noops that return []", function () {
                 if (typeof Performance === "undefined") {
                     return this.skip();