diff --git a/api.go b/api.go
index 356a265..6e6626e 100644
--- a/api.go
+++ b/api.go
@@ -115,7 +115,7 @@ func getMe(token string) (User, error) {
 
 	err = json.Unmarshal(meJSON, &botInfo)
 	if err != nil {
-		return User{}, err
+		return User{}, AuthError{"invalid token"}
 	}
 
 	if botInfo.Ok {
diff --git a/bot.go b/bot.go
index 1595785..04428c0 100644
--- a/bot.go
+++ b/bot.go
@@ -163,7 +163,9 @@ func (b Bot) SendPhoto(recipient User, photo *Photo, options *SendOptions) error
 	}
 
 	thumbnails := &responseRecieved.Result.Photo
+	filename := photo.filename
 	photo.File = (*thumbnails)[len(*thumbnails)-1].File
+	photo.filename = filename
 
 	return nil
 }
@@ -212,7 +214,9 @@ func (b Bot) SendAudio(recipient User, audio *Audio, options *SendOptions) error
 		return SendError{responseRecieved.Description}
 	}
 
+	filename := audio.filename
 	*audio = responseRecieved.Result.Audio
+	audio.filename = filename
 
 	return nil
 }
@@ -261,7 +265,9 @@ func (b Bot) SendDocument(recipient User, doc *Document, options *SendOptions) e
 		return SendError{responseRecieved.Description}
 	}
 
+	filename := doc.filename
 	*doc = responseRecieved.Result.Document
+	doc.filename = filename
 
 	return nil
 }
@@ -310,7 +316,9 @@ func (b *Bot) SendSticker(recipient User, sticker *Sticker, options *SendOptions
 		return SendError{responseRecieved.Description}
 	}
 
+	filename := sticker.filename
 	*sticker = responseRecieved.Result.Sticker
+	sticker.filename = filename
 
 	return nil
 }
@@ -359,7 +367,9 @@ func (b Bot) SendVideo(recipient User, video *Video, options *SendOptions) error
 		return SendError{responseRecieved.Description}
 	}
 
+	filename := video.filename
 	*video = responseRecieved.Result.Video
+	video.filename = filename
 
 	return nil
 }
diff --git a/file.go b/file.go
index 47e8b72..2e2cbb4 100644
--- a/file.go
+++ b/file.go
@@ -10,8 +10,7 @@ type File struct {
 	FileID   string `json:"file_id"`
 	FileSize int    `json:"file_size"`
 
-	// Local absolute path to file on file system. Valid only for
-	// new files, meant to be uploaded soon.
+	// Local absolute path to file on local file system.
 	filename string
 }
 
@@ -30,11 +29,17 @@ func NewFile(path string) (File, error) {
 	return File{filename: path}, nil
 }
 
-// Exists says whether file presents on Telegram servers or not.
+// Exists says whether the file presents on Telegram servers or not.
 func (f File) Exists() bool {
-	if f.filename == "" {
+	if f.FileID != "" {
 		return true
 	}
 
 	return false
 }
+
+// Local returns location of file on local file system, if it's
+// actually there, otherwise returns empty string.
+func (f File) Local() string {
+	return f.filename
+}
diff --git a/telebot_test.go b/telebot_test.go
index 7adb06d..ae3a545 100644
--- a/telebot_test.go
+++ b/telebot_test.go
@@ -6,7 +6,11 @@ import (
 	"testing"
 )
 
-func TestTelebot(t *testing.T) {
+func TestBot(t *testing.T) {
+	if testing.Short() {
+		t.Skip("skipping test in short mode.")
+	}
+
 	token := os.Getenv("TELEBOT_SECRET")
 	if token == "" {
 		fmt.Println("ERROR: " +
@@ -17,28 +21,43 @@ func TestTelebot(t *testing.T) {
 	}
 
 	_, err := NewBot(token)
+	if err != nil {
+		t.Fatal("Couldn't create bot:", err)
+	}
+}
+
+func TestFile(t *testing.T) {
+	file, err := NewFile("telebot.go")
 	if err != nil {
 		t.Fatal(err)
 	}
 
-	// TODO: Uncomment when Telegram fixes behavior for self-messaging
+	if file.Exists() {
+		t.Fatal("Newly created file can't exist on Telegram servers!")
+	}
 
-	/*messages := make(chan Message)
+	file.FileID = "magic"
 
-	intelligence := "welcome to the jungle"
+	if !file.Exists() {
+		t.Fatal("File with defined FileID is supposed to exist, fail.")
+	}
 
-	bot.SendMessage(bot.Identity, intelligence)
-	bot.Listen(messages, 1*time.Second)
-
-	select {
-	case message := <-messages:
-		{
-			if message.Text != intelligence {
-				t.Error("Self-handshake failed.")
-			}
-		}
-
-	case <-time.After(5 * time.Second):
-		t.Error("Self-handshake test took too long, aborting.")
-	}*/
+	if file.Local() != "telebot.go" {
+		t.Fatal("File doesn't preserve its original filename.")
+	}
+}
+
+func TestUser(t *testing.T) {
+	user := User{Title: "bazinga"}
+
+	// According to API, user object with non-empty Title is a group chat.
+	if !user.IsGroupChat() {
+		t.Fatal("Can't tell users/bots and group chats apart!")
+	}
+
+	// Reverse.
+	user.Title = ""
+	if user.IsGroupChat() {
+		t.Fatal("Can't tell users/bots and group chats apart!")
+	}
 }
diff --git a/types.go b/types.go
index 210f3d3..9216a6c 100644
--- a/types.go
+++ b/types.go
@@ -1,16 +1,27 @@
 package telebot
 
 // User object represents a Telegram user, bot or group chat.
+//
+// Title field differs a group chat apart from users and bots:
+// object represents a group chat if Title is empty.
 type User struct {
 	ID        int    `json:"id"`
 	FirstName string `json:"first_name"`
 	LastName  string `json:"last_name"`
 	Username  string `json:"username"`
 
-	// Title differs a group chat apart from users and bots.
 	Title string `json:"title"`
 }
 
+// IsGroupChat returns true if user object represents a group chat.
+func (u User) IsGroupChat() bool {
+	if u.Title != "" {
+		return true
+	}
+
+	return false
+}
+
 // Update object represents an incoming update.
 type Update struct {
 	ID      int     `json:"update_id"`