1 files changed, 122 insertions, 0 deletions
diff --git a/intl/benchmarks/perftest_dateTimeFormat.js b/intl/benchmarks/perftest_dateTimeFormat.js
new file mode 100644
index 0000000000..ffb75d0464
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+++ b/intl/benchmarks/perftest_dateTimeFormat.js
@@ -0,0 +1,122 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+// @ts-check
+
+var perfMetadata = {
+  owner: "Internationalization Team",
+  name: "Intl.DateTimeFormat",
+  description: "Test the speed of the Intl.DateTimeFormat implementation.",
+  options: {
+    default: {
+      perfherder: true,
+      perfherder_metrics: [
+        {
+          name: "Intl.DateTimeFormat constructor iterations",
+          unit: "iterations",
+        },
+        { name: "Intl.DateTimeFormat constructor accumulatedTime", unit: "ms" },
+        { name: "Intl.DateTimeFormat constructor perCallTime", unit: "ms" },
+
+        {
+          name: "Intl.DateTimeFormat.prototype.format iterations",
+          unit: "iterations",
+        },
+        {
+          name: "Intl.DateTimeFormat.prototype.format accumulatedTime",
+          unit: "ms",
+        },
+        {
+          name: "Intl.DateTimeFormat.prototype.format perCallTime",
+          unit: "ms",
+        },
+      ],
+      verbose: true,
+    },
+  },
+  tags: ["intl", "ecma402"],
+};
+
+add_task(function measure_date() {
+  const measureConstructor = measureIterations(
+    "Intl.DateTimeFormat constructor"
+  );
+  const measureFormat = measureIterations(
+    "Intl.DateTimeFormat.prototype.format"
+  );
+
+  // Re-use the config between runs.
+
+  const fieldOptions = {
+    weekday: ["narrow", "short", "long"],
+    era: ["narrow", "short", "long"],
+    year: ["2-digit", "numeric"],
+    month: ["2-digit", "numeric", "narrow", "short", "long"],
+    day: ["2-digit", "numeric"],
+    hour: ["2-digit", "numeric"],
+    minute: ["2-digit", "numeric"],
+    second: ["2-digit", "numeric"],
+    timeZoneName: ["short", "long"],
+  };
+
+  const config = {};
+  function randomizeConfig(name, chance) {
+    const option = fieldOptions[name];
+    if (prng() < chance) {
+      config[name] = option[Math.floor(option.length * prng())];
+    } else {
+      delete config[name];
+    }
+  }
+
+  let date = new Date(Date.UTC(2020, 11, 20, 3, 23, 16, 738));
+
+  // Split each step of the benchmark into separate JS functions so that performance
+  // profiles are easy to analyze.
+
+  function benchmarkDateTimeFormatConstructor() {
+    for (let i = 0; i < 1000; i++) {
+      // Create a random configuration powered by a pseudo-random number generator. This
+      // way the configurations will be the same between 2 different runs.
+      const locale = pickRepresentativeLocale();
+      randomizeConfig("year", 0.5);
+      randomizeConfig("month", 0.5);
+      randomizeConfig("day", 0.5);
+      randomizeConfig("hour", 0.5);
+      randomizeConfig("minute", 0.5);
+      // Set the following to some lower probabilities:
+      randomizeConfig("second", 0.2);
+      randomizeConfig("timeZoneName", 0.2);
+      randomizeConfig("weekday", 0.2);
+      randomizeConfig("era", 0.1);
+
+      // Measure the constructor.
+      measureConstructor.start();
+      const formatter = Intl.DateTimeFormat(locale, config);
+      // Also include one format operation to ensure the constructor is de-lazified.
+      formatter.format(date);
+      measureConstructor.stop();
+
+      benchmarkFormatOperation(formatter);
+    }
+  }
+
+  const start = Date.UTC(2000);
+  const end = Date.UTC(2030);
+  const dateDiff = end - start;
+  function benchmarkFormatOperation(formatter) {
+    // Measure the format operation.
+    for (let j = 0; j < 100; j++) {
+      date = new Date(start + prng() * dateDiff);
+      measureFormat.start();
+      formatter.format(date);
+      measureFormat.stop();
+    }
+  }
+
+  benchmarkDateTimeFormatConstructor();
+  measureConstructor.reportMetrics();
+  measureFormat.reportMetrics();
+
+  ok(true);
+});