1 files changed, 88 insertions, 0 deletions
diff --git a/helix-tui/tests/widgets_list.rs b/helix-tui/tests/widgets_list.rs
new file mode 100644
index 00000000..e59accd8
--- /dev/null
+++ b/helix-tui/tests/widgets_list.rs
@@ -0,0 +1,88 @@
+use helix_tui::{
+    backend::TestBackend,
+    buffer::Buffer,
+    layout::Rect,
+    style::{Color, Style},
+    symbols,
+    widgets::{Block, Borders, List, ListItem, ListState},
+    Terminal,
+};
+
+#[test]
+fn widgets_list_should_highlight_the_selected_item() {
+    let backend = TestBackend::new(10, 3);
+    let mut terminal = Terminal::new(backend).unwrap();
+    let mut state = ListState::default();
+    state.select(Some(1));
+    terminal
+        .draw(|f| {
+            let size = f.size();
+            let items = vec![
+                ListItem::new("Item 1"),
+                ListItem::new("Item 2"),
+                ListItem::new("Item 3"),
+            ];
+            let list = List::new(items)
+                .highlight_style(Style::default().bg(Color::Yellow))
+                .highlight_symbol(">> ");
+            f.render_stateful_widget(list, size, &mut state);
+        })
+        .unwrap();
+    let mut expected = Buffer::with_lines(vec!["   Item 1 ", ">> Item 2 ", "   Item 3 "]);
+    for x in 0..10 {
+        expected.get_mut(x, 1).set_bg(Color::Yellow);
+    }
+    terminal.backend().assert_buffer(&expected);
+}
+
+#[test]
+fn widgets_list_should_truncate_items() {
+    let backend = TestBackend::new(10, 2);
+    let mut terminal = Terminal::new(backend).unwrap();
+
+    struct TruncateTestCase<'a> {
+        selected: Option<usize>,
+        items: Vec<ListItem<'a>>,
+        expected: Buffer,
+    }
+
+    let cases = vec![
+        // An item is selected
+        TruncateTestCase {
+            selected: Some(0),
+            items: vec![
+                ListItem::new("A very long line"),
+                ListItem::new("A very long line"),
+            ],
+            expected: Buffer::with_lines(vec![
+                format!(">> A ve{}  ", symbols::line::VERTICAL),
+                format!("   A ve{}  ", symbols::line::VERTICAL),
+            ]),
+        },
+        // No item is selected
+        TruncateTestCase {
+            selected: None,
+            items: vec![
+                ListItem::new("A very long line"),
+                ListItem::new("A very long line"),
+            ],
+            expected: Buffer::with_lines(vec![
+                format!("A very {}  ", symbols::line::VERTICAL),
+                format!("A very {}  ", symbols::line::VERTICAL),
+            ]),
+        },
+    ];
+    for case in cases {
+        let mut state = ListState::default();
+        state.select(case.selected);
+        terminal
+            .draw(|f| {
+                let list = List::new(case.items.clone())
+                    .block(Block::default().borders(Borders::RIGHT))
+                    .highlight_symbol(">> ");
+                f.render_stateful_widget(list, Rect::new(0, 0, 8, 2), &mut state);
+            })
+            .unwrap();
+        terminal.backend().assert_buffer(&case.expected);
+    }
+}