feat: toggle wrapping in shell output windows

src/tui.rs

@@ -2906,7 +2906,7 @@ fn draw_overlays(
         draw_startup_diagnostic(frame, diagnostic, area);
     }
     if let Some(output) = editor.command_output() {
-        draw_diagnostic_panel(frame, &output.content, area, &output.title, false);
+        draw_diagnostic_panel(frame, &output.content, area, &output.title, Some(output));
     }
 }
 
@@ -4631,7 +4631,7 @@ fn floating_panel(area: Rect) -> Rect {
 }
 
 fn draw_startup_diagnostic(frame: &mut Frame, diagnostic: &StartupDiagnostic, area: Rect) {
-    draw_diagnostic_panel(frame, diagnostic, area, "Configuration error", true);
+    draw_diagnostic_panel(frame, diagnostic, area, "Configuration error", None);
 }
 
 fn draw_diagnostic_panel(
@@ -4639,8 +4639,9 @@ fn draw_diagnostic_panel(
     diagnostic: &StartupDiagnostic,
     area: Rect,
     title: &str,
-    startup: bool,
+    output: Option<&crate::editor::ShellOutput>,
 ) {
+    let startup = output.is_none();
     let panel = floating_panel(area);
     frame.render_widget(Clear, panel);
     let bordered = panel.width >= 4 && panel.height >= 4;
@@ -4661,26 +4662,60 @@ fn draw_diagnostic_panel(
         Constraint::Length(u16::from(content.height >= 3)),
     ])
     .areas(content);
-    let lines: Vec<Line> = diagnostic
-        .lines
-        .iter()
-        .skip(diagnostic.top)
-        .take(usize::from(text_area.height))
-        .map(|line| {
-            let line = display_text(line);
-            Line::from(visible_line(
-                &line,
-                display_column(&line, diagnostic.left),
-                usize::from(text_area.width),
-            ))
-        })
-        .collect();
+    let lines: Vec<Line> = if let Some(output) = output.filter(|output| output.wrapping) {
+        let width = usize::from(text_area.width).max(1);
+        let mut cached = output.wrapped_lines.borrow_mut();
+        if cached.0 != width {
+            let mut cache = crate::wrap::WrapCache::default();
+            cache.prepare((0, 0), width);
+            cached.1.clear();
+            for (row, line) in diagnostic.lines.iter().enumerate() {
+                let segments = cache.segments(row, line);
+                for (index, segment) in segments.iter().enumerate() {
+                    // Output has no insertion caret: omit its extra empty continuation.
+                    if index == 0 || segment.start != segment.end {
+                        cached.1.push((row, *segment));
+                    }
+                }
+            }
+            cached.0 = width;
+        }
+        output.wrapped_rows.set(cached.1.len());
+        cached
+            .1
+            .iter()
+            .skip(diagnostic.top.min(cached.1.len().saturating_sub(1)))
+            .take(usize::from(text_area.height))
+            .map(|(row, segment)| {
+                Line::from(visible_line(
+                    &diagnostic.lines[*row],
+                    segment.start,
+                    (segment.end - segment.start).min(width),
+                ))
+            })
+            .collect()
+    } else {
+        diagnostic
+            .lines
+            .iter()
+            .skip(diagnostic.top)
+            .take(usize::from(text_area.height))
+            .map(|line| {
+                let line = display_text(line);
+                Line::from(visible_line(
+                    &line,
+                    display_column(&line, diagnostic.left),
+                    usize::from(text_area.width),
+                ))
+            })
+            .collect()
+    };
     frame.render_widget(Paragraph::new(lines), text_area);
     frame.render_widget(
         Paragraph::new(if startup {
             "Arrows scroll · Home reset · Enter/Esc continue"
         } else {
-            "Arrows scroll · Home reset · Enter/Esc close"
+            "w wrap · Arrows scroll · Home reset · Enter/Esc close"
         })
         .style(Style::default().fg(Color::DarkGray)),
         help_area,