Add simple testing infrastructure

vendor/github.com/onsi/ginkgo/internal/writer/writer.go

@@ -0,0 +1,71 @@
+package writer
+
+import (
+	"bytes"
+	"io"
+	"sync"
+)
+
+type WriterInterface interface {
+	io.Writer
+
+	Truncate()
+	DumpOut()
+	DumpOutWithHeader(header string)
+}
+
+type Writer struct {
+	buffer    *bytes.Buffer
+	outWriter io.Writer
+	lock      *sync.Mutex
+	stream    bool
+}
+
+func New(outWriter io.Writer) *Writer {
+	return &Writer{
+		buffer:    &bytes.Buffer{},
+		lock:      &sync.Mutex{},
+		outWriter: outWriter,
+		stream:    true,
+	}
+}
+
+func (w *Writer) SetStream(stream bool) {
+	w.lock.Lock()
+	defer w.lock.Unlock()
+	w.stream = stream
+}
+
+func (w *Writer) Write(b []byte) (n int, err error) {
+	w.lock.Lock()
+	defer w.lock.Unlock()
+
+	if w.stream {
+		return w.outWriter.Write(b)
+	} else {
+		return w.buffer.Write(b)
+	}
+}
+
+func (w *Writer) Truncate() {
+	w.lock.Lock()
+	defer w.lock.Unlock()
+	w.buffer.Reset()
+}
+
+func (w *Writer) DumpOut() {
+	w.lock.Lock()
+	defer w.lock.Unlock()
+	if !w.stream {
+		w.buffer.WriteTo(w.outWriter)
+	}
+}
+
+func (w *Writer) DumpOutWithHeader(header string) {
+	w.lock.Lock()
+	defer w.lock.Unlock()
+	if !w.stream && w.buffer.Len() > 0 {
+		w.outWriter.Write([]byte(header))
+		w.buffer.WriteTo(w.outWriter)
+	}
+}