move error_accumulator into internal pkg (#304) (#335)

* move error_accumulator into internal pkg (#304)

* move error_accumulator into internal pkg (#304)

* add a test for ErrTooManyEmptyStreamMessages in stream_reader (#304)

stream_reader_test.go

@@ -0,0 +1,53 @@
+package openai //nolint:testpackage // testing private field
+
+import (
+	"bufio"
+	"bytes"
+	"errors"
+	"testing"
+
+	utils "github.com/sashabaranov/go-openai/internal"
+)
+
+var errTestUnmarshalerFailed = errors.New("test unmarshaler failed")
+
+type failingUnMarshaller struct{}
+
+func (*failingUnMarshaller) Unmarshal(_ []byte, _ any) error {
+	return errTestUnmarshalerFailed
+}
+
+func TestStreamReaderReturnsUnmarshalerErrors(t *testing.T) {
+	stream := &streamReader[ChatCompletionStreamResponse]{
+		errAccumulator: utils.NewErrorAccumulator(),
+		unmarshaler:    &failingUnMarshaller{},
+	}
+
+	respErr := stream.unmarshalError()
+	if respErr != nil {
+		t.Fatalf("Did not return nil with empty buffer: %v", respErr)
+	}
+
+	err := stream.errAccumulator.Write([]byte("{"))
+	if err != nil {
+		t.Fatalf("%+v", err)
+	}
+
+	respErr = stream.unmarshalError()
+	if respErr != nil {
+		t.Fatalf("Did not return nil when unmarshaler failed: %v", respErr)
+	}
+}
+
+func TestStreamReaderReturnsErrTooManyEmptyStreamMessages(t *testing.T) {
+	stream := &streamReader[ChatCompletionStreamResponse]{
+		emptyMessagesLimit: 3,
+		reader:             bufio.NewReader(bytes.NewReader([]byte("\n\n\n\n"))),
+		errAccumulator:     utils.NewErrorAccumulator(),
+		unmarshaler:        &utils.JSONUnmarshaler{},
+	}
+	_, err := stream.Recv()
+	if !errors.Is(err, ErrTooManyEmptyStreamMessages) {
+		t.Fatalf("Did not return error when recv failed: %v", err)
+	}
+}