garnet/bin/ui/tests/performance/process_trace_helpers_test.go

package main

import (
	"math"
	"testing"

	"fuchsia.googlesource.com/benchmarking"
)

func almostEqual(a float64, b float64) bool {
	return math.Abs(a-b) < 1e-6
}

func TestCalculateFpsForEvents(t *testing.T) {
	events := []*benchmarking.Event{
		&benchmarking.Event{
			Start: 3.4*OneSecInUsecs,
			Dur: 0.01*OneSecInUsecs,
		},
		&benchmarking.Event{
			Start: 3.6*OneSecInUsecs,
			Dur: 0.01*OneSecInUsecs,
		},
		&benchmarking.Event{
			Start: 3.9*OneSecInUsecs,
			Dur: 0.01*OneSecInUsecs,
		},
		&benchmarking.Event{
			Start: 4.35*OneSecInUsecs,
			Dur: 0.01*OneSecInUsecs,
		},
		&benchmarking.Event{
			Start: 4.5*OneSecInUsecs,
			Dur: 0.01*OneSecInUsecs,
		},
		&benchmarking.Event{
			Start: 4.9*OneSecInUsecs,
			Dur: 0.01*OneSecInUsecs,
		},
		&benchmarking.Event{
			Start: 5.4*OneSecInUsecs,
			Dur: 0.01*OneSecInUsecs,
		},
		&benchmarking.Event{
			Start: 7.2*OneSecInUsecs,
			Dur: 0.01*OneSecInUsecs,
		},
		&benchmarking.Event{
			Start: 7.5*OneSecInUsecs,
			Dur: 0.01*OneSecInUsecs,
		},
		&benchmarking.Event{
			Start: 10.5*OneSecInUsecs,
			Dur: 0.01*OneSecInUsecs,
		},
		&benchmarking.Event{
			Start: 10.6*OneSecInUsecs,
			Dur: 0.01*OneSecInUsecs,
		},
		&benchmarking.Event{
			Start: 10.7*OneSecInUsecs,
			Dur: 0.01*OneSecInUsecs,
		},
	}
	expectedFps := 12.0 / 7.3
	expectedFpsPerWindow := []float64{4, 2, 1, 1, 1, 0, 0}
	fps, fpsPerWindow := calculateFpsForEvents(events);
	if !almostEqual(fps, expectedFps) {
		t.Errorf("Calculated incorrect fps: got %f, expected %f", fps, expectedFps)
	}
	if len(fpsPerWindow) != len(expectedFpsPerWindow) {
		t.Errorf("Expected %d windows, got %d", len(expectedFpsPerWindow), len(fpsPerWindow))
	}
	for i, expected := range expectedFpsPerWindow {
		if !almostEqual(fpsPerWindow[i], expected) {
			t.Errorf("Window %d got %f fps, expected %f", i, fpsPerWindow[i], expected)
		}
	}
}