fix: Fix to return nil when dict info cannot be read

dict/dict_info.go

@@ -13,8 +13,6 @@ type Info struct {
 	Src  string
 }
 
-const UndefinedDictName = "unnamed dict"
-
 // ReadDictInfo reads gob encoded dictionary info and returns it.
 //
 // For backward compatibility, if a dictionary name is not defined or empty, it
@@ -25,12 +23,13 @@ func ReadDictInfo(r io.Reader) *Info {
 	}
 	var name string
 	dec := gob.NewDecoder(r)
-	_ = dec.Decode(&name)
-	if name == "" {
-		name = UndefinedDictName
+	if err := dec.Decode(&name); err != nil {
+		return nil
 	}
 	var src string
-	_ = dec.Decode(&src)
+	if err := dec.Decode(&src); err != nil {
+		return nil
+	}
 	return &Info{Name: name, Src: src}
 }
 

dict/dict_info_test.go

@@ -35,33 +35,24 @@ func TestDictName_bad_input(t *testing.T) {
 
 		// Decode gob encoded dictionary name.
 		got := ReadDictInfo(&gobName)
-
-		// Assert be equal to default name.
-		want := UndefinedDictName
-		if want != got.Name {
-			t.Errorf("empty name should return default name. want %v, got %v", want, got.Name)
+		if got.Name != "" {
+			t.Errorf("empty name should return empty name. got %v", got)
 		}
 	})
 
 	t.Run("nil input", func(t *testing.T) {
 		// Nil input shuold return default name.
 		got := ReadDictInfo(nil)
-
-		// Assert be equal to default name.
-		want := UndefinedDictName
-		if want != got.Name {
-			t.Errorf("nil input should return default name. want %v, got %v", want, got)
+		if got != nil {
+			t.Errorf("nil input should return nil. got %v", got)
 		}
 	})
 
 	t.Run("bad gob data", func(t *testing.T) {
 		// Bad gob data should return default name.
 		got := ReadDictInfo(bytes.NewReader([]byte{0x00}))
-
-		// Assert be equal to default name.
-		want := UndefinedDictName
-		if want != got.Name {
-			t.Errorf("bad encoded data should return default name. want %v, got %v", want, got)
+		if got != nil {
+			t.Errorf("bad gob data should return nil. got %v", got)
 		}
 	})
 }