feat: emphasize keybinding overview headings

src/keys.rs

@@ -1,6 +1,10 @@
 use std::{fmt::Write as _, io};
 
 use ratatui::crossterm::event::{KeyCode, KeyEvent, KeyModifiers};
+use ratatui::{
+    style::Stylize,
+    text::{Line, Span, Text},
+};
 use toml_edit::{Array, Item};
 
 #[derive(Clone, Copy, Debug, PartialEq, Eq)]
@@ -419,25 +423,28 @@ impl Bindings {
             .map_or("unbound", String::as_str)
     }
 
-    pub fn help_text(&self) -> String {
-        let mut text = String::from("Keyboard bindings\n\n");
+    pub fn help_text(&self) -> Text<'static> {
+        let mut text = Text::from(Line::from(Span::raw("Keyboard bindings").bold()));
+        text.push_line("");
         for definition in DEFINITIONS {
             let aliases = &self.labels[definition.action as usize];
-            let bindings = if aliases.is_empty() {
-                "unbound".to_owned()
+            let mut body = String::from(": ");
+            if aliases.is_empty() {
+                body.push_str("unbound");
             } else {
-                aliases.join(", ")
-            };
-            let _ = write!(
-                text,
-                "{}: {} — {} [",
-                definition.name, bindings, definition.description
-            );
+                for (index, alias) in aliases.iter().enumerate() {
+                    if index != 0 {
+                        body.push_str(", ");
+                    }
+                    body.push_str(alias);
+                }
+            }
+            let _ = write!(body, " — {} [", definition.description);
             for (index, context) in definition.contexts.iter().enumerate() {
                 if index != 0 {
-                    text.push_str(", ");
+                    body.push_str(", ");
                 }
-                text.push_str(match context {
+                body.push_str(match context {
                     Context::Normal => "video list",
                     Context::Info => "video overview",
                     Context::Description => "video description",
@@ -449,11 +456,18 @@ impl Bindings {
                     Context::Help => "help",
                 });
             }
-            text.push_str("]\n");
+            body.push(']');
+            text.push_line(Line::from(vec![
+                Span::raw(definition.name).bold(),
+                Span::raw(body),
+            ]));
         }
-        text.push_str("\nText input inserts literal characters; normal-mode commands do not run there.\n\
-Shared overview/description bindings cycle overview → description → overview; distinct bindings open either view directly.\n\
-Preview close takes priority over history back. Description scrolling takes priority over video selection on shared bindings.\n");
+        text.push_line("");
+        text.push_line(
+            "Text input inserts literal characters; normal-mode commands do not run there.",
+        );
+        text.push_line("Shared overview/description bindings cycle overview → description → overview; distinct bindings open either view directly.");
+        text.push_line("Preview close takes priority over history back. Description scrolling takes priority over video selection on shared bindings.");
         text
     }
 }
@@ -519,6 +533,60 @@ mod tests {
         bindings.resolve(context, KeyEvent::new(code, modifiers))
     }
 
+    #[test]
+    fn help_headings_are_bold_but_bindings_and_descriptions_are_not() {
+        use ratatui::{
+            buffer::Buffer,
+            layout::Rect,
+            style::Modifier,
+            widgets::{Paragraph, Widget, Wrap},
+        };
+        let bindings = configured("[keys]\napp.interrupt = 'f24'\n").unwrap();
+        for width in [21, 64] {
+            let area = Rect::new(0, 0, width, 8);
+            let mut buffer = Buffer::empty(area);
+            Paragraph::new(bindings.help_text())
+                .wrap(Wrap { trim: false })
+                .render(area, &mut buffer);
+            assert!(buffer[(0, 0)].modifier.contains(Modifier::BOLD));
+            for x in 0.."app.interrupt".len() as u16 {
+                assert!(buffer[(x, 2)].modifier.contains(Modifier::BOLD));
+            }
+            assert!(
+                !buffer[("app.interrupt".len() as u16, 2)]
+                    .modifier
+                    .contains(Modifier::BOLD)
+            );
+            let mut found_binding = false;
+            for y in 2..area.height {
+                let row = (0..width)
+                    .map(|x| buffer[(x, y)].symbol())
+                    .collect::<String>();
+                if y > 2 && row.starts_with("app.quit") {
+                    break;
+                }
+                let body_start = if y == 2 {
+                    "app.interrupt".len() as u16
+                } else {
+                    0
+                };
+                for x in body_start..width {
+                    assert!(!buffer[(x, y)].modifier.contains(Modifier::BOLD));
+                }
+                if let Some(x) = row.find("F24") {
+                    found_binding = true;
+                    for x in x as u16..x as u16 + 3 {
+                        assert!(!buffer[(x, y)].modifier.contains(Modifier::BOLD));
+                    }
+                }
+            }
+            assert!(
+                found_binding,
+                "configured binding must remain visible after wrapping"
+            );
+        }
+    }
+
     #[test]
     fn contextual_cycle_and_direct_preview_bindings() {
         let defaults = Bindings::default();