From 43a123c1ae6613b3efeed291fa552ecd909d3acf Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Tue, 16 Apr 2024 21:23:18 +0200 Subject: Adding upstream version 1.20.14. Signed-off-by: Daniel Baumann --- src/time/tick_test.go | 177 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 177 insertions(+) create mode 100644 src/time/tick_test.go (limited to 'src/time/tick_test.go') diff --git a/src/time/tick_test.go b/src/time/tick_test.go new file mode 100644 index 0000000..f539091 --- /dev/null +++ b/src/time/tick_test.go @@ -0,0 +1,177 @@ +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package time_test + +import ( + "fmt" + "runtime" + "testing" + . "time" +) + +func TestTicker(t *testing.T) { + // We want to test that a ticker takes as much time as expected. + // Since we don't want the test to run for too long, we don't + // want to use lengthy times. This makes the test inherently flaky. + // Start with a short time, but try again with a long one if the + // first test fails. + + baseCount := 10 + baseDelta := 20 * Millisecond + + // On Darwin ARM64 the tick frequency seems limited. Issue 35692. + if (runtime.GOOS == "darwin" || runtime.GOOS == "ios") && runtime.GOARCH == "arm64" { + // The following test will run ticker count/2 times then reset + // the ticker to double the duration for the rest of count/2. + // Since tick frequency is limited on Darwin ARM64, use even + // number to give the ticks more time to let the test pass. + // See CL 220638. + baseCount = 6 + baseDelta = 100 * Millisecond + } + + var errs []string + logErrs := func() { + for _, e := range errs { + t.Log(e) + } + } + + for _, test := range []struct { + count int + delta Duration + }{{ + count: baseCount, + delta: baseDelta, + }, { + count: 8, + delta: 1 * Second, + }} { + count, delta := test.count, test.delta + ticker := NewTicker(delta) + t0 := Now() + for i := 0; i < count/2; i++ { + <-ticker.C + } + ticker.Reset(delta * 2) + for i := count / 2; i < count; i++ { + <-ticker.C + } + ticker.Stop() + t1 := Now() + dt := t1.Sub(t0) + target := 3 * delta * Duration(count/2) + slop := target * 3 / 10 + if dt < target-slop || dt > target+slop { + errs = append(errs, fmt.Sprintf("%d %s ticks then %d %s ticks took %s, expected [%s,%s]", count/2, delta, count/2, delta*2, dt, target-slop, target+slop)) + if dt > target+slop { + // System may be overloaded; sleep a bit + // in the hopes it will recover. + Sleep(Second / 2) + } + continue + } + // Now test that the ticker stopped. + Sleep(2 * delta) + select { + case <-ticker.C: + errs = append(errs, "Ticker did not shut down") + continue + default: + // ok + } + + // Test passed, so all done. + if len(errs) > 0 { + t.Logf("saw %d errors, ignoring to avoid flakiness", len(errs)) + logErrs() + } + + return + } + + t.Errorf("saw %d errors", len(errs)) + logErrs() +} + +// Issue 21874 +func TestTickerStopWithDirectInitialization(t *testing.T) { + c := make(chan Time) + tk := &Ticker{C: c} + tk.Stop() +} + +// Test that a bug tearing down a ticker has been fixed. This routine should not deadlock. +func TestTeardown(t *testing.T) { + Delta := 100 * Millisecond + if testing.Short() { + Delta = 20 * Millisecond + } + for i := 0; i < 3; i++ { + ticker := NewTicker(Delta) + <-ticker.C + ticker.Stop() + } +} + +// Test the Tick convenience wrapper. +func TestTick(t *testing.T) { + // Test that giving a negative duration returns nil. + if got := Tick(-1); got != nil { + t.Errorf("Tick(-1) = %v; want nil", got) + } +} + +// Test that NewTicker panics when given a duration less than zero. +func TestNewTickerLtZeroDuration(t *testing.T) { + defer func() { + if err := recover(); err == nil { + t.Errorf("NewTicker(-1) should have panicked") + } + }() + NewTicker(-1) +} + +// Test that Ticker.Reset panics when given a duration less than zero. +func TestTickerResetLtZeroDuration(t *testing.T) { + defer func() { + if err := recover(); err == nil { + t.Errorf("Ticker.Reset(0) should have panicked") + } + }() + tk := NewTicker(Second) + tk.Reset(0) +} + +func BenchmarkTicker(b *testing.B) { + benchmark(b, func(n int) { + ticker := NewTicker(Nanosecond) + for i := 0; i < n; i++ { + <-ticker.C + } + ticker.Stop() + }) +} + +func BenchmarkTickerReset(b *testing.B) { + benchmark(b, func(n int) { + ticker := NewTicker(Nanosecond) + for i := 0; i < n; i++ { + ticker.Reset(Nanosecond * 2) + } + ticker.Stop() + }) +} + +func BenchmarkTickerResetNaive(b *testing.B) { + benchmark(b, func(n int) { + ticker := NewTicker(Nanosecond) + for i := 0; i < n; i++ { + ticker.Stop() + ticker = NewTicker(Nanosecond * 2) + } + ticker.Stop() + }) +} -- cgit v1.2.3