AR='ar'
CC='clang'
CGO_CFLAGS='-O2 -g'
CGO_CPPFLAGS=''
CGO_CXXFLAGS='-O2 -g'
CGO_ENABLED='1'
CGO_FFLAGS='-O2 -g'
CGO_LDFLAGS='-O2 -g'
CXX='clang++'
GCCGO='gccgo'
GO111MODULE=''
GOARCH='arm64'
GOARM64='v8.0'
GOAUTH='netrc'
GOBIN=''
GOCACHE='/Users/catatsuy/Library/Caches/go-build'
GOCACHEPROG=''
GODEBUG=''
GOENV='/Users/catatsuy/Library/Application Support/go/env'
GOEXE=''
GOEXPERIMENT=''
GOFIPS140='off'
GOFLAGS=''
GOGCCFLAGS='-fPIC -arch arm64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -ffile-prefix-map=/var/folders/ys/lyy3yrnx07d9_2sdq_gb5ys00000gn/T/go-build3620988728=/tmp/go-build -gno-record-gcc-switches -fno-common'
GOHOSTARCH='arm64'
GOHOSTOS='darwin'
GOINSECURE=''
GOMOD='/Users/catatsuy/go/src/github.com/catatsuy/synctest_examples/go.mod'
GOMODCACHE='/Users/catatsuy/go/pkg/mod'
GONOPROXY=''
GONOSUMDB=''
GOOS='darwin'
GOPATH='/Users/catatsuy/go'
GOPRIVATE=''
GOPROXY='direct'
GOROOT='/usr/local/go'
GOSUMDB='sum.golang.org'
GOTELEMETRY='local'
GOTELEMETRYDIR='/Users/catatsuy/Library/Application Support/go/telemetry'
GOTMPDIR=''
GOTOOLCHAIN=''
GOTOOLDIR='/usr/local/go/pkg/tool/darwin_arm64'
GOVCS=''
GOVERSION='go1.25.0'
GOWORK=''
PKG_CONFIG='pkg-config'

package synctest_examples
import (
	"bufio"
	"context"
	"io"
	"testing"
	"testing/synctest"
	"time"
)
type Exec struct {
	r *bufio.Reader
}
func NewExec(pr *io.PipeReader) *Exec {
	return &Exec{r: bufio.NewReader(pr)}
}
func (ex *Exec) Start(ctx context.Context, interval <-chan time.Time, flush func(string), done func(string)) {
	// Reader stops only on EOF.
	go func() {
		for {
			_, _, err := ex.r.ReadLine()
			if err != nil {
				return
			} // EOF only
		}
	}()
	select {
	case <-interval:
		flush("")
	case <-ctx.Done():
		done("")
		// returns, but the reader goroutine is still blocked if writer is not closed
	}
}
func Test_IOPipe_cancel_deadlocks(t *testing.T) {
	synctest.Test(t, func(t *testing.T) {
		pr, pw := io.Pipe()
		ex := NewExec(pr)
		ctx, cancel := context.WithCancel(context.Background())
		interval := make(chan time.Time)
		done := make(chan struct{})
		go func() {
			ex.Start(ctx, interval, func(string) {}, func(string) {})
			close(done)
		}()
		// Write one line, then cancel WITHOUT closing pw:
		pw.Write([]byte("abc\n"))
		cancel()
		<-done
		// At test end, synctest panics:
		// panic: deadlock: main bubble goroutine has exited but blocked goroutines remain
		_ = pw
	})
}

--- FAIL: Test_IOPipe_cancel_deadlocks (0.00s)
panic: deadlock: main bubble goroutine has exited but blocked goroutines remain [recovered, repanicked]
goroutine 5 [running]:
testing.tRunner.func1.2({0x104a69d80, 0x1400000c0c0})
	/usr/local/go/src/testing/testing.go:1872 +0x190
testing.tRunner.func1()
	/usr/local/go/src/testing/testing.go:1875 +0x31c
panic({0x104a69d80?, 0x1400000c0c0?})
	/usr/local/go/src/runtime/panic.go:783 +0x120
internal/synctest.Run(0x140001061e0)
	/usr/local/go/src/runtime/synctest.go:251 +0x2c4
testing/synctest.Test(0x14000003500, 0x104a81b18)
	/usr/local/go/src/testing/synctest/synctest.go:282 +0x88
github.com/catatsuy/synctest_examples.Test_IOPipe_cancel_deadlocks(0x14000003500?)
	/Users/catatsuy/go/src/github.com/catatsuy/synctest_examples/se_test.go:40 +0x24
testing.tRunner(0x14000003500, 0x104a81a80)
	/usr/local/go/src/testing/testing.go:1934 +0xc8
created by testing.(*T).Run in goroutine 1
	/usr/local/go/src/testing/testing.go:1997 +0x364
goroutine 33 [select (durable), synctest bubble 1]:
io.(*pipe).read(0x14000070300, {0x1400012d000, 0x1000, 0x0?})
	/usr/local/go/src/io/pipe.go:57 +0x7c
io.(*PipeReader).Read(0x0?, {0x1400012d000?, 0x0?, 0x0?})
	/usr/local/go/src/io/pipe.go:134 +0x24
bufio.(*Reader).fill(0x14000070360)
	/usr/local/go/src/bufio/bufio.go:113 +0xe0
bufio.(*Reader).ReadSlice(0x14000070360, 0xa)
	/usr/local/go/src/bufio/bufio.go:380 +0x30
bufio.(*Reader).ReadLine(0x14000070360)
	/usr/local/go/src/bufio/bufio.go:409 +0x24
github.com/catatsuy/synctest_examples.(*Exec).Start.func1()
	/Users/catatsuy/go/src/github.com/catatsuy/synctest_examples/se_test.go:24 +0x30
created by github.com/catatsuy/synctest_examples.(*Exec).Start in goroutine 8
	/Users/catatsuy/go/src/github.com/catatsuy/synctest_examples/se_test.go:22 +0x70
FAIL	github.com/catatsuy/synctest_examples	0.260s
FAIL

func Test_IOPipe_cancel_with_close_ok(t *testing.T) {
	synctest.Test(t, func(t *testing.T) {
		pr, pw := io.Pipe()
		ex := NewExec(pr)
		ctx, cancel := context.WithCancel(context.Background())
		interval := make(chan time.Time)
		done := make(chan struct{})
		go func() {
			ex.Start(ctx, interval, func(string) {}, func(string) {})
			close(done)
		}()
		pw.Write([]byte("abc\n"))
		// Close to send EOF so the reader goroutine exits:
		_ = pw.Close()
		cancel()
		<-done
	})
}