Performance.measure: handle the case with a single startMark argument correctly (#37888)

Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/37888

# Changelog:
[Internal] -

There was one particular permutation of input arguments to `Performance.measure` that wasn't handled correctly on the native side, namely when there is only the start mark argument present, but not the end time/mark, e.g.:
```
Performance.measure('myMeasure', 'someStartMark');
```

In this case, [according to the standard](https://developer.mozilla.org/en-US/docs/Web/API/Performance/measure), the end time should be taken as the current one:
> The end timestamp is one of:
> ...
>  -the value returned by Performance.now(), if no end mark is specified or can be determined from other values.

It was taken as 0 instead, making the total duration negative and consequently getting it filtered out by the default `durationThreshold` of 0.

I've added a corresponding missing clause in the native unit tests. This also required a slight extension to the `PerformanceObserver` API to allow for mocking the current timestamp provider.

Reviewed By: rubennorte

Differential Revision: D46728261

fbshipit-source-id: bd904d9c93707fa04c1a0ddb30802691e253c106

packages/react-native/Libraries/WebPerformance/PerformanceEntryReporter.cpp

@@ -15,10 +15,6 @@
 namespace facebook::react {
 EventTag PerformanceEntryReporter::sCurrentEventTag_{0};
 
-static inline double getCurrentTimeStamp() {
-  return JSExecutor::performanceNow();
-}
-
 PerformanceEntryReporter &PerformanceEntryReporter::getInstance() {
   static PerformanceEntryReporter instance;
   return instance;
@@ -29,11 +25,17 @@ PerformanceEntryReporter::PerformanceEntryReporter() {
   // sure that marks can be referenced by measures
   getBuffer(PerformanceEntryType::MARK).hasNameLookup = true;
 }
+
 void PerformanceEntryReporter::setReportingCallback(
     std::optional<AsyncCallback<>> callback) {
   callback_ = callback;
 }
 
+double PerformanceEntryReporter::getCurrentTimeStamp() const {
+  return timeStampProvider_ != nullptr ? timeStampProvider_()
+                                       : JSExecutor::performanceNow();
+}
+
 void PerformanceEntryReporter::startReporting(PerformanceEntryType entryType) {
   auto &buffer = getBuffer(entryType);
   buffer.isReporting = true;
@@ -219,7 +221,15 @@ void PerformanceEntryReporter::measure(
     const std::optional<std::string> &endMark) {
   double startTimeVal = startMark ? getMarkTime(*startMark) : startTime;
   double endTimeVal = endMark ? getMarkTime(*endMark) : endTime;
+
+  if (!endMark && endTime < startTimeVal) {
+    // The end time is not specified, take the current time, according to the
+    // standard
+    endTimeVal = getCurrentTimeStamp();
+  }
+
   double durationVal = duration ? *duration : endTimeVal - startTimeVal;
+
   logEntry(
       {name,
        static_cast<int>(PerformanceEntryType::MEASURE),

packages/react-native/Libraries/WebPerformance/PerformanceEntryReporter.h

@@ -147,6 +147,10 @@ class PerformanceEntryReporter : public EventLogger {
     return eventCounts_;
   }
 
+  void setTimeStampProvider(std::function<double()> provider) {
+    timeStampProvider_ = provider;
+  }
+
  private:
   std::optional<AsyncCallback<>> callback_;
 
@@ -171,6 +175,8 @@ class PerformanceEntryReporter : public EventLogger {
   std::unordered_map<EventTag, EventEntry> eventsInFlight_;
   std::mutex eventsInFlightMutex_;
 
+  std::function<double()> timeStampProvider_ = nullptr;
+
   static EventTag sCurrentEventTag_;
 
   PerformanceEntryReporter();
@@ -182,6 +188,8 @@ class PerformanceEntryReporter : public EventLogger {
       PerformanceEntryType entryType,
       const char *entryName,
       std::vector<RawPerformanceEntry> &res) const;
+
+  double getCurrentTimeStamp() const;
 };
 
 } // namespace facebook::react

packages/react-native/Libraries/WebPerformance/__tests__/PerformanceEntryReporterTest.cpp

@@ -146,8 +146,11 @@ TEST(PerformanceEntryReporter, PerformanceEntryReporterTestReportMeasures) {
   reporter.measure("measure3", 0.0, 0.0, 5.0, "mark1");
   reporter.measure("measure4", 1.5, 0.0, std::nullopt, std::nullopt, "mark2");
 
+  reporter.setTimeStampProvider([]() { return 3.5; });
+  reporter.measure("measure5", 0.0, 0.0, std::nullopt, "mark2");
+
   reporter.mark("mark3", 2.0);
-  reporter.measure("measure5", 2.0, 2.0);
+  reporter.measure("measure6", 2.0, 2.0);
   reporter.mark("mark4", 2.0);
 
   auto res = reporter.popPendingEntries();
@@ -226,13 +229,20 @@ TEST(PerformanceEntryReporter, PerformanceEntryReporterTestReportMeasures) {
        std::nullopt,
        std::nullopt,
        std::nullopt},
-      {"measure5",
+      {"measure6",
        static_cast<int>(PerformanceEntryType::MEASURE),
        2.0,
        0.0,
        std::nullopt,
        std::nullopt,
        std::nullopt},
+      {"measure5",
+       static_cast<int>(PerformanceEntryType::MEASURE),
+       2.0,
+       1.5,
+       std::nullopt,
+       std::nullopt,
+       std::nullopt},
   };
 
   ASSERT_EQ(expected, entries);