Added allow-expect-in-tests / allow-unwrap-in-tests (#2328)

This PR:
* Added the clippy.toml to configure allowable expect / unwrap usage in
tests
* Removed as many expect/allow lines as possible from tests
* moved a bunch of allows to expects where possible

Note: in integration tests, non `#[test]` helper functions are not
covered by this so we had to leave a few lingering `expect(expect_used`
checks around

codex-rs/tui/src/app.rs

@@ -188,7 +188,7 @@ impl App<'_> {
                         }
                     }
 
-                    #[allow(clippy::expect_used)]
+                    #[expect(clippy::expect_used)]
                     let deadline = next_deadline.expect("deadline set");
                     let now = Instant::now();
                     let timeout = if deadline > now {

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

@@ -182,7 +182,6 @@ impl ChatComposerHistory {
 
 #[cfg(test)]
 mod tests {
-    #![expect(clippy::expect_used)]
     use super::*;
     use crate::app_event::AppEvent;
     use codex_core::protocol::Op;

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

@@ -801,7 +801,7 @@ impl TextArea {
         }
     }
 
-    #[allow(clippy::unwrap_used)]
+    #[expect(clippy::unwrap_used)]
     fn wrapped_lines(&self, width: u16) -> Ref<'_, Vec<Range<usize>>> {
         // Ensure cache is ready (potentially mutably borrow, then drop)
         {
@@ -926,7 +926,6 @@ impl TextArea {
 }
 
 #[cfg(test)]
-#[allow(clippy::unwrap_used)]
 mod tests {
     use super::*;
     // crossterm types are intentionally not imported here to avoid unused warnings
@@ -1432,7 +1431,6 @@ mod tests {
         // Seed the RNG based on the current day in Pacific Time (PST/PDT). This
         // keeps the fuzz test deterministic within a day while still varying
         // day-to-day to improve coverage.
-        #[allow(clippy::unwrap_used)]
         let pst_today_seed: u64 = (chrono::Utc::now() - chrono::Duration::hours(8))
             .date_naive()
             .and_hms_opt(0, 0, 0)

codex-rs/tui/src/chatwidget/tests.rs

@@ -1,5 +1,3 @@
-#![allow(clippy::unwrap_used, clippy::expect_used, unnameable_test_items)]
-
 use super::*;
 use crate::app_event::AppEvent;
 use crate::app_event_sender::AppEventSender;

codex-rs/tui/src/citation_regex.rs

@@ -1,4 +1,4 @@
-#![allow(clippy::expect_used)]
+#![expect(clippy::expect_used)]
 
 use regex_lite::Regex;
 

codex-rs/tui/src/diff_render.rs

@@ -357,7 +357,6 @@ fn style_del() -> Style {
     Style::default().fg(Color::Red)
 }
 
-#[allow(clippy::expect_used)]
 #[cfg(test)]
 mod tests {
     use super::*;

codex-rs/tui/src/file_search.rs

@@ -31,10 +31,7 @@ use std::time::Duration;
 use crate::app_event::AppEvent;
 use crate::app_event_sender::AppEventSender;
 
-#[allow(clippy::unwrap_used)]
 const MAX_FILE_SEARCH_RESULTS: NonZeroUsize = NonZeroUsize::new(8).unwrap();
-
-#[allow(clippy::unwrap_used)]
 const NUM_FILE_SEARCH_THREADS: NonZeroUsize = NonZeroUsize::new(2).unwrap();
 
 /// How long to wait after a keystroke before firing the first search when none
@@ -84,7 +81,7 @@ impl FileSearchManager {
     /// Call whenever the user edits the `@` token.
     pub fn on_user_query(&self, query: String) {
         {
-            #[allow(clippy::unwrap_used)]
+            #[expect(clippy::unwrap_used)]
             let mut st = self.state.lock().unwrap();
             if query == st.latest_query {
                 // No change, nothing to do.
@@ -125,7 +122,7 @@ impl FileSearchManager {
             // `active_search` is cleared.
             thread::sleep(FILE_SEARCH_DEBOUNCE);
             loop {
-                #[allow(clippy::unwrap_used)]
+                #[expect(clippy::unwrap_used)]
                 if state.lock().unwrap().active_search.is_none() {
                     break;
                 }
@@ -137,7 +134,7 @@ impl FileSearchManager {
             let cancellation_token = Arc::new(AtomicBool::new(false));
             let token = cancellation_token.clone();
             let query = {
-                #[allow(clippy::unwrap_used)]
+                #[expect(clippy::unwrap_used)]
                 let mut st = state.lock().unwrap();
                 let query = st.latest_query.clone();
                 st.is_search_scheduled = false;
@@ -188,7 +185,7 @@ impl FileSearchManager {
             // that we are clearing the ActiveSearch that corresponds to the
             // cancellation token we were given.
             {
-                #[allow(clippy::unwrap_used)]
+                #[expect(clippy::unwrap_used)]
                 let mut st = search_state.lock().unwrap();
                 if let Some(active_search) = &st.active_search {
                     if Arc::ptr_eq(&active_search.cancellation_token, &cancellation_token) {

codex-rs/tui/src/insert_history.rs

@@ -379,7 +379,6 @@ fn slice_line_spans(
 
 #[cfg(test)]
 mod tests {
-    #![allow(clippy::unwrap_used)]
     use super::*;
 
     #[test]

codex-rs/tui/src/lib.rs

@@ -295,7 +295,6 @@ fn restore() {
     }
 }
 
-#[allow(clippy::unwrap_used)]
 fn should_show_login_screen(config: &Config) -> bool {
     if config.model_provider.requires_openai_auth {
         // Reading the OpenAI API key is an async operation because it may need

codex-rs/tui/src/text_formatting.rs

@@ -102,7 +102,6 @@ pub(crate) fn truncate_text(text: &str, max_graphemes: usize) -> String {
 
 #[cfg(test)]
 mod tests {
-    #![allow(clippy::unwrap_used)]
     use super::*;
     use pretty_assertions::assert_eq;