Skip to content

chore: add example test case for clock package #13465

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Jun 5, 2024
Merged

chore: add example test case for clock package #13465

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
84 changes: 84 additions & 0 deletions clock/example_test.go
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,84 @@
package clock_test

import (
"context"
"sync"
"testing"
"time"

"github.com/coder/coder/v2/clock"
)

type exampleTickCounter struct {
ctx context.Context
mu sync.Mutex
ticks int
clock clock.Clock
}

func (c *exampleTickCounter) Ticks() int {
c.mu.Lock()
defer c.mu.Unlock()
return c.ticks
}

func (c *exampleTickCounter) count() {
_ = c.clock.TickerFunc(c.ctx, time.Hour, func() error {
c.mu.Lock()
defer c.mu.Unlock()
c.ticks++
return nil
}, "mytag")
}

func newExampleTickCounter(ctx context.Context, clk clock.Clock) *exampleTickCounter {
tc := &exampleTickCounter{ctx: ctx, clock: clk}
go tc.count()
return tc
}

// TestExampleTickerFunc demonstrates how to test the use of TickerFunc.
func TestExampleTickerFunc(t *testing.T) {
t.Parallel()
// nolint:gocritic // trying to avoid Coder-specific stuff with an eye toward spinning this out
ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
defer cancel()

mClock := clock.NewMock()

// Because the ticker is started on a goroutine, we can't immediately start
// advancing the clock, or we will race with the start of the ticker. If we
// win that race, the clock gets advanced _before_ the ticker starts, and
// our ticker will not get a tick.
//
// To handle this, we set a trap for the call to TickerFunc(), so that we
// can assert it has been called before advancing the clock.
trap := mClock.Trap().TickerFunc("mytag")
defer trap.Close()

tc := newExampleTickCounter(ctx, mClock)

// Here, we wait for our trap to be triggered.
call, err := trap.Wait(ctx)
if err != nil {
t.Fatal("ticker never started")
}
// it's good practice to release calls before any possible t.Fatal() calls
// so that we don't leave dangling goroutines waiting for the call to be
// released.
call.Release()
if call.Duration != time.Hour {
t.Fatal("unexpected duration")
}

if tks := tc.Ticks(); tks != 0 {
t.Fatalf("expected 0 got %d ticks", tks)
}

// Now that we know the ticker is started, we can advance the time.
mClock.Advance(time.Hour).MustWait(ctx, t)

if tks := tc.Ticks(); tks != 1 {
t.Fatalf("expected 1 got %d ticks", tks)
}
}
Loading