import (
	"context"
	"fmt"
	"os/exec"
	"time"

	"github.com/sourcegraph/sourcegraph/internal/memcmd"
)

func Example() {
	const template = `
#!/usr/bin/env bash
set -euo pipefail

word=$(head -c "$((10 * 1024 * 1024))" </dev/zero | tr '\0' '\141') # 10MB worth of 'a's
sleep 1
echo ${#word}
`

	cmd := exec.Command("bash", "-c", template)
	err := cmd.Start()
	if err != nil {
		panic(err)
	}

	observer, err := memcmd.NewLinuxObserver(context.Background(), cmd, 1*time.Millisecond)
	if err != nil {
		panic(err)
	}

	observer.Start()
	defer observer.Stop()

	err = cmd.Wait()
	if err != nil {
		panic(err)
	}

	memoryUsage, err := observer.MaxMemoryUsage()
	if err != nil {
		panic(err)
	}

	fmt.Println((0 < memoryUsage && memoryUsage < 50*1024*1024)) // Output should be between 0 and 50MB

	// Output:
	// true
}