benchmark: use Stopwatch over DateTime for benchmarking (#491)
Use built-in String.padLeft
diff --git a/benchmark/benchmark.dart b/benchmark/benchmark.dart
index 63a8d1f..aaf8112 100644
--- a/benchmark/benchmark.dart
+++ b/benchmark/benchmark.dart
@@ -19,7 +19,7 @@
// Run the benchmark several times. This ensures the VM is warmed up and lets
// us see how much variance there is.
for (var i = 0; i <= numTrials; i++) {
- final start = DateTime.now();
+ final stopwatch = Stopwatch()..start();
// For a single benchmark, convert the source multiple times.
late String result;
@@ -27,8 +27,8 @@
result = markdownToHtml(source);
}
- final elapsed =
- DateTime.now().difference(start).inMilliseconds / runsPerTrial;
+ stopwatch.stop();
+ final elapsed = stopwatch.elapsedMilliseconds / runsPerTrial;
// Keep track of the best run so far.
if (elapsed >= best) continue;
@@ -45,7 +45,7 @@
// Don't print the first run. It's always terrible since the VM hasn't
// warmed up yet.
if (i == 0) continue;
- _printResult("Run ${_padLeft('#$i', 3)}", elapsed);
+ _printResult("Run ${'#$i'.padLeft(3)}", elapsed);
}
_printResult('Best ', best);
@@ -57,15 +57,8 @@
}
void _printResult(String label, double time) {
- print('$label: ${_padLeft(time.toStringAsFixed(2), 4)}ms '
- "${'=' * ((time * 20).toInt())}");
-}
-
-String _padLeft(String input, int length) {
- var result = input.toString();
- if (result.length < length) {
- result = ' ' * (length - result.length) + result;
- }
-
- return result;
+ print(
+ '$label: ${time.toStringAsFixed(2).padLeft(4)}ms '
+ "${'=' * ((time * 20).toInt())}",
+ );
}
