Multiple fixes: signed/unsigned, etc... (#600)

Co-authored-by: ArthurSonzogni <sonzogniarthur@gmail.com>

include/ftxui/component/event.hpp

@@ -66,11 +66,11 @@ struct Event {
   std::string character() const { return input_; }
 
   bool is_mouse() const { return type_ == Type::Mouse; }
-  struct Mouse& mouse() { return mouse_; }
+  struct Mouse& mouse() { return data_.mouse; }
 
   bool is_cursor_reporting() const { return type_ == Type::CursorReporting; }
-  int cursor_x() const { return cursor_.x; }
-  int cursor_y() const { return cursor_.y; }
+  int cursor_x() const { return data_.cursor.x; }
+  int cursor_y() const { return data_.cursor.y; }
 
   const std::string& input() const { return input_; }
 
@@ -92,14 +92,15 @@ struct Event {
   Type type_ = Type::Unknown;
 
   struct Cursor {
-    int x;
-    int y;
+    int x = 0;
+    int y = 0;
   };
 
   union {
-    struct Mouse mouse_;
-    struct Cursor cursor_;
-  };
+    struct Mouse mouse;
+    struct Cursor cursor;
+  } data_ = {};
+
   std::string input_;
 };
 

include/ftxui/component/mouse.hpp

@@ -21,19 +21,19 @@ struct Mouse {
   };
 
   // Button
-  Button button;
+  Button button = Button::None;
 
   // Motion
-  Motion motion;
+  Motion motion = Motion::Pressed;
 
   // Modifiers:
-  bool shift;
-  bool meta;
-  bool control;
+  bool shift = false;
+  bool meta = false;
+  bool control = false;
 
   // Coordinates:
-  int x;
-  int y;
+  int x = 0;
+  int y = 0;
 };
 
 }  // namespace ftxui