feat: adding built-in mark to compare to get better metrics

CHANGELOG.md

@@ -7,6 +7,36 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ## [Unreleased][]
 
+### Updated
+
+- `end()`: Adding built-in mark to compare if the application is not passing the values. This will give us all the required information for the consumers.
+
+Without passing a mark to compare
+
+```js
+import * as PerfMarks from 'perf-marks';
+
+...
+PerfMarks.start('name-of-your-mark');
+...
+const markResults: PerfMarks.PerfMarksPerformanceEntry = PerfMarks.end('name-of-your-mark');
+```
+
+Passing a mark to compare
+
+```js
+import * as PerfMarks from 'perf-marks';
+
+...
+PerfMarks.start('name-of-your-mark');
+PerfMarks.start('name-of-your-mark-to-be-compared-with');
+...
+const markResults: PerfMarks.PerfMarksPerformanceEntry = PerfMarks.end(
+  'name-of-your-mark',
+  'name-of-your-mark-to-be-compared-with'
+);
+```
+
 ## [1.13.4][] - 2020-08-21
 
 ### Fixed
@@ -359,7 +389,5 @@ if (PerfMarks.isPerformanceObservableSupported) {
 [1.13.2]: https://github.com/willmendesneto/perf-marks/tree/v1.13.2
 [unreleased]: https://github.com/willmendesneto/perf-marks/compare/v1.13.3...HEAD
 [1.13.3]: https://github.com/willmendesneto/perf-marks/tree/v1.13.3
-
-
-[Unreleased]: https://github.com/willmendesneto/perf-marks/compare/v1.13.4...HEAD
-[1.13.4]: https://github.com/willmendesneto/perf-marks/tree/v1.13.4
+[unreleased]: https://github.com/willmendesneto/perf-marks/compare/v1.13.4...HEAD
+[1.13.4]: https://github.com/willmendesneto/perf-marks/tree/v1.13.4

README.md

@@ -111,12 +111,16 @@ PerfMarks.start('name-of-your-mark');
 ...
 ```
 
-### `PerfMarks.end(markName)`
+### `PerfMarks.end(markName, markNameToCompare)`
 
 Returns the results for the specified marker.
 
 > `PerfMarks.end(markName)` calls `PerfMarks.clear(markName)` after return the mark values
 
+If `markNameToCompare` value is not passed, the package will create a mark using `markName + '-end'`. Otherwise, it will compare based on the given mark.
+
+> If you're passing `markNameToCompare` value, please make sure you're also started the mark with the same name previously
+
 ```js
 import * as PerfMarks from 'perf-marks';
 

src/__tests__/perf-marks.ts

@@ -88,7 +88,7 @@ describe('PerfMarks: User timing API is available', () => {
     ]);
 
     const mark = 'mark';
-    const secondMark = 'mark-end';
+    const secondMark = 'mark-end-of-measurement';
 
     PerfMarks.start(mark);
     PerfMarks.start(secondMark);
@@ -100,6 +100,28 @@ describe('PerfMarks: User timing API is available', () => {
     expect(performance.clearMeasures).toHaveBeenNthCalledWith(2, secondMark);
   });
 
+  it('should remove mark and compared mark with the one created internally if second parameter was NOT passed to `end()`', () => {
+    jest.spyOn(performance, 'getEntriesByName').mockImplementation(() => [
+      {
+        duration: 1,
+        startTime: 2,
+        toJSON: () => null,
+        entryType: '',
+        name: '',
+      },
+    ]);
+
+    const mark = 'mark';
+
+    PerfMarks.start(mark);
+    PerfMarks.end(mark);
+
+    expect(performance.clearMarks).toHaveBeenNthCalledWith(1, mark);
+    expect(performance.clearMarks).toHaveBeenNthCalledWith(2, `${mark}-end`);
+    expect(performance.clearMeasures).toHaveBeenNthCalledWith(1, mark);
+    expect(performance.clearMeasures).toHaveBeenNthCalledWith(2, `${mark}-end`);
+  });
+
   it('should return user timing information if user finishes mark', () => {
     const mark = 'mark';
     PerfMarks.start(mark);

src/__tests__/profiler.ts

@@ -61,13 +61,13 @@ describe('PerfMarks: User timing API is NOT available', () => {
     expect(performance.getEntriesByName(markProfiler)).toHaveLength(0);
   });
 
-  it('should run profile if receives callback as promise', async () => {
+  it('should run profile if receives callback as promise', async function PROFILING_TEST() {
     const functionToBeProfiled = () =>
       // eslint-disable-next-line compat/compat
       new Promise(resolve => {
         return setTimeout(() => {
           resolve(testFunction());
-        }, 500);
+        }, 5);
       });
 
     const result = await profiler(functionToBeProfiled, markProfiler);

src/marks.ts

@@ -32,7 +32,7 @@ const clear = (markName: string): void => {
   marksMap[markName] = undefined;
 
   // Removes PerformanceObserver references from memory
-  if (marksObserver[markName]) {
+  if (!!marksObserver[markName]) {
     marksObserver[markName] = undefined;
   }
 
@@ -93,11 +93,20 @@ const end = (markName: string, markNameToCompare?: string): PerfMarksPerformance
   try {
     const startTime = marksMap[markName];
 
-    // NodeJS is not using performance api directly from them for now
-    if (!isUserTimingAPISupported || isNodeJSEnv) {
-      // `performance.measure()` behaves diferently between frontend and
-      // backend in Javascript applications. Using based on NodeJS docs
-      performance.measure(markName, markName, markNameToCompare || markName);
+    if (!isUserTimingAPISupported) {
+      return startTime
+        ? ({ duration: getTimeNow() - startTime, startTime, entryType: 'measure', name: markName } as PerformanceEntry)
+        : {};
+    }
+    // If there's no User Timing mark to be compared with,
+    // the package will create one to be used for better comparison
+    if (!markNameToCompare) {
+      performance.mark(`${markName}-end`);
+    }
+
+    performance.measure(markName, markName, markNameToCompare || `${markName}-end`);
+
+    if (isNodeJSEnv) {
       if (!!marksObserver[markName]) {
         return marksObserver[markName] as PerfMarksPerformanceEntry;
       }
@@ -106,7 +115,6 @@ const end = (markName: string, markNameToCompare?: string): PerfMarksPerformance
         : {};
     }
 
-    performance.measure(markName, markName, markNameToCompare || undefined);
     const entry: PerformanceEntry | undefined = performance.getEntriesByName(markName).pop();
 
     return entry || {};
@@ -115,15 +123,13 @@ const end = (markName: string, markNameToCompare?: string): PerfMarksPerformance
     // This could only happen if something in event loop crashed
     // in an unexpected place earlier.
     // Don't pile on with more errors.
-
     return {};
   } finally {
     // Clear marks immediately to avoid growing buffer.
     clear(markName);
     // Clear marks used for comparison in case of it's value was passed
-    if (markNameToCompare) {
-      clear(markNameToCompare);
-    }
+    // If the mark to compare is not passed, it should remove the one we create with `-end` suffix
+    clear(markNameToCompare || `${markName}-end`);
   }
 };