Add tests for keypresses

Pressing "up"/"k" at the top of the UI will now go to the end of the list. And
same in reverse.

src/client/ui.rs

@@ -383,11 +383,12 @@ impl UI {
                     }
                 }
                 KeyEvent { code: KeyCode::Up, .. }
-                | KeyEvent { code: KeyCode::Char('j'), .. } => {
+                | KeyEvent { code: KeyCode::Char('k'), .. } => {
                     let index = match self.selection.selected() {
                         Some(i) => {
+                            assert!(self.ports.len() > 0, "We must have ports because we have a selection.");
                             if i == 0 {
-                                0
+                                self.ports.len() - 1
                             } else {
                                 i - 1
                             }
@@ -397,11 +398,11 @@ impl UI {
                     self.selection.select(Some(index));
                 }
                 KeyEvent { code: KeyCode::Down, .. }
-                | KeyEvent { code: KeyCode::Char('k'), .. } => {
+                | KeyEvent { code: KeyCode::Char('j'), .. } => {
                     let index = match self.selection.selected() {
                         Some(i) => {
                             assert!(self.ports.len() > 0, "We must have ports because we have a selection.");
-                            (i + 1).min(self.ports.len() - 1)
+                            (i + 1) % self.ports.len()
                         }
                         None => 0,
                     };
@@ -572,6 +573,73 @@ mod tests {
         assert_eq!(ui.ports.len(), 2);
         assert_matches!(ui.selection.selected(), Some(0));
 
+        // Move selection up => wraps around the length
+        ui.handle_console_event(Some(Ok(Event::Key(KeyEvent::new(
+            KeyCode::Up,
+            KeyModifiers::empty(),
+        )))));
+        assert_matches!(ui.selection.selected(), Some(1));
+        ui.handle_console_event(Some(Ok(Event::Key(KeyEvent::new(
+            KeyCode::Up,
+            KeyModifiers::empty(),
+        )))));
+        assert_matches!(ui.selection.selected(), Some(0));
+        ui.handle_console_event(Some(Ok(Event::Key(KeyEvent::new(
+            KeyCode::Up,
+            KeyModifiers::empty(),
+        )))));
+        assert_matches!(ui.selection.selected(), Some(1));
+
+        // Move selection down => wraps around the length
+        ui.handle_console_event(Some(Ok(Event::Key(KeyEvent::new(
+            KeyCode::Down,
+            KeyModifiers::empty(),
+        )))));
+        assert_matches!(ui.selection.selected(), Some(0));
+        ui.handle_console_event(Some(Ok(Event::Key(KeyEvent::new(
+            KeyCode::Down,
+            KeyModifiers::empty(),
+        )))));
+        assert_matches!(ui.selection.selected(), Some(1));
+        ui.handle_console_event(Some(Ok(Event::Key(KeyEvent::new(
+            KeyCode::Down,
+            KeyModifiers::empty(),
+        )))));
+        assert_matches!(ui.selection.selected(), Some(0));
+
+        // J and K move the correct direction
+        ui.handle_internal_event(Some(UIEvent::Ports(vec![
+            PortDesc {
+                port: 8080,
+                desc: "my-service".to_string(),
+            },
+            PortDesc {
+                port: 8081,
+                desc: "my-service".to_string(),
+            },
+            PortDesc {
+                port: 8082,
+                desc: "my-service".to_string(),
+            },
+        ])));
+        assert_eq!(ui.ports.len(), 3);
+
+        // J is down
+        ui.selection.select(Some(1));
+        ui.handle_console_event(Some(Ok(Event::Key(KeyEvent::new(
+            KeyCode::Char('j'),
+            KeyModifiers::empty(),
+        )))));
+        assert_matches!(ui.selection.selected(), Some(2));
+
+        // K is up
+        ui.selection.select(Some(1));
+        ui.handle_console_event(Some(Ok(Event::Key(KeyEvent::new(
+            KeyCode::Char('k'),
+            KeyModifiers::empty(),
+        )))));
+        assert_matches!(ui.selection.selected(), Some(0));
+
         drop(sender);
     }