Example of goroutine leak when using time.After with an unbuffered channel

timeafterleak_test.go

package timeafterleak_test

import (
        "log"
        "testing"
        "time"

        "github.com/fortytw2/leaktest"
)

func TestUnbuffered(t *testing.T) {
        defer leaktest.Check(t)()
        ch := make(chan string)
        waitForResult(ch)
}

func TestBuffered(t *testing.T) {
        defer leaktest.Check(t)()
        ch := make(chan string, 1)
        waitForResult(ch)
}

func waitForResult(ch chan(string)) {
        go func() {
                time.Sleep(500 * time.Millisecond)
                ret := "done"
                ch <- ret
        }()

        select {
        case res := <-ch:
                log.Println(res)
        case <-time.After(100 * time.Millisecond):
                log.Println("timed out")
        }
}
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