feat: highlight matching characters in fuzzy file search (#1420)

Using the new file-search API introduced in
https://github.com/openai/codex/pull/1419, matching characters are now
shown in bold in the TUI:


https://github.com/user-attachments/assets/8bbcc6c6-75a3-493f-8ea4-b2a063e09b3a

Fixes https://github.com/openai/codex/issues/1261

codex-rs/tui/src/app_event.rs

@@ -1,4 +1,5 @@
 use codex_core::protocol::Event;
+use codex_file_search::FileMatch;
 use crossterm::event::KeyEvent;
 
 use crate::slash_command::SlashCommand;
@@ -39,6 +40,6 @@ pub(crate) enum AppEvent {
     /// still relevant.
     FileSearchResult {
         query: String,
-        matches: Vec<String>,
+        matches: Vec<FileMatch>,
     },
 }

codex-rs/tui/src/bottom_pane/chat_composer.rs

@@ -20,6 +20,7 @@ use super::file_search_popup::FileSearchPopup;
 
 use crate::app_event::AppEvent;
 use crate::app_event_sender::AppEventSender;
+use codex_file_search::FileMatch;
 
 /// Minimum number of visible text rows inside the textarea.
 const MIN_TEXTAREA_ROWS: usize = 1;
@@ -129,7 +130,7 @@ impl ChatComposer<'_> {
     }
 
     /// Integrate results from an asynchronous file search.
-    pub(crate) fn on_file_search_result(&mut self, query: String, matches: Vec<String>) {
+    pub(crate) fn on_file_search_result(&mut self, query: String, matches: Vec<FileMatch>) {
         // Only apply if user is still editing a token starting with `query`.
         let current_opt = Self::current_at_token(&self.textarea);
         let Some(current_token) = current_opt else {

codex-rs/tui/src/bottom_pane/file_search_popup.rs

@@ -1,8 +1,12 @@
+use codex_file_search::FileMatch;
 use ratatui::buffer::Buffer;
 use ratatui::layout::Rect;
 use ratatui::prelude::Constraint;
 use ratatui::style::Color;
+use ratatui::style::Modifier;
 use ratatui::style::Style;
+use ratatui::text::Line;
+use ratatui::text::Span;
 use ratatui::widgets::Block;
 use ratatui::widgets::BorderType;
 use ratatui::widgets::Borders;
@@ -25,7 +29,7 @@ pub(crate) struct FileSearchPopup {
     /// When `true` we are still waiting for results for `pending_query`.
     waiting: bool,
     /// Cached matches; paths relative to the search dir.
-    matches: Vec<String>,
+    matches: Vec<FileMatch>,
     /// Currently selected index inside `matches` (if any).
     selected_idx: Option<usize>,
 }
@@ -63,7 +67,7 @@ impl FileSearchPopup {
 
     /// Replace matches when a `FileSearchResult` arrives.
     /// Replace matches. Only applied when `query` matches `pending_query`.
-    pub(crate) fn set_matches(&mut self, query: &str, matches: Vec<String>) {
+    pub(crate) fn set_matches(&mut self, query: &str, matches: Vec<FileMatch>) {
         if query != self.pending_query {
             return; // stale
         }
@@ -101,7 +105,7 @@ impl FileSearchPopup {
     pub(crate) fn selected_match(&self) -> Option<&str> {
         self.selected_idx
             .and_then(|idx| self.matches.get(idx))
-            .map(String::as_str)
+            .map(|file_match| file_match.path.as_str())
     }
 
     /// Preferred height (rows) including border.
@@ -130,11 +134,36 @@ impl WidgetRef for &FileSearchPopup {
                 .iter()
                 .take(MAX_RESULTS)
                 .enumerate()
-                .map(|(i, p)| {
+                .map(|(i, file_match)| {
-                    let mut cell = Cell::from(p.as_str());
+                    let FileMatch { path, indices, .. } = file_match;
+                    let path = path.as_str();
+                    #[allow(clippy::expect_used)]
+                    let indices = indices.as_ref().expect("indices should be present");
+
+                    // Build spans with bold on matching indices.
+                    let mut idx_iter = indices.iter().peekable();
+                    let mut spans: Vec<Span> = Vec::with_capacity(path.len());
+
+                    for (char_idx, ch) in path.chars().enumerate() {
+                        let mut style = Style::default();
+                        if idx_iter
+                            .peek()
+                            .is_some_and(|next| **next == char_idx as u32)
+                        {
+                            idx_iter.next();
+                            style = style.add_modifier(Modifier::BOLD);
+                        }
+                        spans.push(Span::styled(ch.to_string(), style));
+                    }
+
+                    // Create cell from the spans.
+                    let mut cell = Cell::from(Line::from(spans));
+
+                    // If selected, also paint yellow.
                     if Some(i) == self.selected_idx {
                         cell = cell.style(Style::default().fg(Color::Yellow));
                     }
+
                     Row::new(vec![cell])
                 })
                 .collect()

codex-rs/tui/src/bottom_pane/mod.rs

@@ -1,16 +1,16 @@
 //! Bottom pane: shows the ChatComposer or a BottomPaneView, if one is active.
 
-use bottom_pane_view::BottomPaneView;
-use bottom_pane_view::ConditionalUpdate;
-use codex_core::protocol::TokenUsage;
-use crossterm::event::KeyEvent;
-use ratatui::buffer::Buffer;
-use ratatui::layout::Rect;
-use ratatui::widgets::WidgetRef;
-
 use crate::app_event::AppEvent;
 use crate::app_event_sender::AppEventSender;
 use crate::user_approval_widget::ApprovalRequest;
+use bottom_pane_view::BottomPaneView;
+use bottom_pane_view::ConditionalUpdate;
+use codex_core::protocol::TokenUsage;
+use codex_file_search::FileMatch;
+use crossterm::event::KeyEvent;
+use ratatui::buffer::Buffer;
+use ratatui::layout::Rect;
+use ratatui::widgets::WidgetRef;
 
 mod approval_modal_view;
 mod bottom_pane_view;
@@ -228,7 +228,7 @@ impl BottomPane<'_> {
         }
     }
 
-    pub(crate) fn on_file_search_result(&mut self, query: String, matches: Vec<String>) {
+    pub(crate) fn on_file_search_result(&mut self, query: String, matches: Vec<FileMatch>) {
         self.composer.on_file_search_result(query, matches);
         self.request_redraw();
     }

codex-rs/tui/src/chatwidget.rs

@@ -38,6 +38,7 @@ use crate::bottom_pane::InputResult;
 use crate::conversation_history_widget::ConversationHistoryWidget;
 use crate::history_cell::PatchEventType;
 use crate::user_approval_widget::ApprovalRequest;
+use codex_file_search::FileMatch;
 
 pub(crate) struct ChatWidget<'a> {
     app_event_tx: AppEventSender,
@@ -405,7 +406,7 @@ impl ChatWidget<'_> {
     }
 
     /// Forward file-search results to the bottom pane.
-    pub(crate) fn apply_file_search_result(&mut self, query: String, matches: Vec<String>) {
+    pub(crate) fn apply_file_search_result(&mut self, query: String, matches: Vec<FileMatch>) {
         self.bottom_pane.on_file_search_result(query, matches);
     }
 

codex-rs/tui/src/file_search.rs

@@ -165,7 +165,7 @@ impl FileSearchManager {
         cancellation_token: Arc<AtomicBool>,
         search_state: Arc<Mutex<SearchState>>,
     ) {
-        let compute_indices = false;
+        let compute_indices = true;
         std::thread::spawn(move || {
             let matches = file_search::run(
                 &query,
@@ -176,12 +176,7 @@ impl FileSearchManager {
                 cancellation_token.clone(),
                 compute_indices,
             )
-            .map(|res| {
+            .map(|res| res.matches)
-                res.matches
-                    .into_iter()
-                    .map(|m| m.path)
-                    .collect::<Vec<String>>()
-            })
             .unwrap_or_default();
 
             let is_cancelled = cancellation_token.load(Ordering::Relaxed);