Added unit tests for all the new widgets

src/ui/widgets/button_tests.rs

@@ -0,0 +1,41 @@
+#[cfg(test)]
+mod tests {
+  use crate::ui::widgets::button::Button;
+  use pretty_assertions::{assert_eq, assert_str_eq};
+  use ratatui::style::{Style, Stylize};
+
+  #[test]
+  fn test_title() {
+    let button = Button::default().title("Title");
+
+    assert_str_eq!(button.title, "Title");
+  }
+
+  #[test]
+  fn test_label() {
+    let button = Button::default().label("Label");
+
+    assert_eq!(button.label, Some("Label"));
+  }
+
+  #[test]
+  fn test_icon() {
+    let button = Button::default().icon("Icon");
+
+    assert_eq!(button.icon, Some("Icon"));
+  }
+
+  #[test]
+  fn test_style() {
+    let button = Button::default().style(Style::new().bold());
+
+    assert_eq!(button.style, Style::new().bold());
+  }
+
+  #[test]
+  fn test_selected() {
+    let button = Button::default().selected(true);
+
+    assert!(button.is_selected);
+  }
+}