allow empty headers on DataFromReader (#2121)

context_test.go

@@ -1799,6 +1799,23 @@ func TestContextRenderDataFromReader(t *testing.T) {
 	assert.Equal(t, extraHeaders["Content-Disposition"], w.Header().Get("Content-Disposition"))
 }
 
+func TestContextRenderDataFromReaderNoHeaders(t *testing.T) {
+	w := httptest.NewRecorder()
+	c, _ := CreateTestContext(w)
+
+	body := "#!PNG some raw data"
+	reader := strings.NewReader(body)
+	contentLength := int64(len(body))
+	contentType := "image/png"
+
+	c.DataFromReader(http.StatusOK, contentLength, contentType, reader, nil)
+
+	assert.Equal(t, http.StatusOK, w.Code)
+	assert.Equal(t, body, w.Body.String())
+	assert.Equal(t, contentType, w.Header().Get("Content-Type"))
+	assert.Equal(t, fmt.Sprintf("%d", contentLength), w.Header().Get("Content-Length"))
+}
+
 type TestResponseRecorder struct {
 	*httptest.ResponseRecorder
 	closeChannel chan bool