moby--moby/pkg/ioutils/readers_test.go

package ioutils

import (
	"bytes"
	"io"
	"io/ioutil"
	"testing"
)

func TestBufReader(t *testing.T) {
	reader, writer := io.Pipe()
	bufreader := NewBufReader(reader)

	// Write everything down to a Pipe
	// Usually, a pipe should block but because of the buffered reader,
	// the writes will go through
	done := make(chan bool)
	go func() {
		writer.Write([]byte("hello world"))
		writer.Close()
		done <- true
	}()

	// Drain the reader *after* everything has been written, just to verify
	// it is indeed buffering
	<-done
	output, err := ioutil.ReadAll(bufreader)
	if err != nil {
		t.Fatal(err)
	}
	if !bytes.Equal(output, []byte("hello world")) {
		t.Error(string(output))
	}
}