T23: the shell tests type a line only once the line editor reads raw keys: on CI's pwsh 7.6.6 the probe, typed right after the first folder report, came before PSReadLine's first read and was echoed, never run; shot warns when the app it runs under lacks Screen Recording, which left this Mac's pictures with the window's ground alone; AGENTS.md records the CI runners, the build without debuginfo and the typing rule

src/term/pty.rs

@@ -56,6 +56,8 @@ pub struct Pty {
     pub term: Arc<FairMutex<Term<Listener>>>,
     pub pid: u32,
     notifier: Notifier,
+    #[cfg(all(test, unix))]
+    master: std::fs::File,
 }
 
 /// What a pty reports, in order.
@@ -109,6 +111,10 @@ pub fn spawn(
         )
     })?;
     let pid = child_id(&raw)?;
+    #[cfg(all(test, unix))]
+    let master = raw
+        .master()
+        .map_err(|error| anyhow::anyhow!("pty {pid}: no copy of the master: {error}"))?;
     log::info!(
         "pty {pid}: started {:?} in {}",
         launch.program,
@@ -135,6 +141,8 @@ pub fn spawn(
             term,
             pid,
             notifier,
+            #[cfg(all(test, unix))]
+            master,
         },
         events,
     ))
@@ -176,6 +184,16 @@ impl Pty {
     }
 }
 
+#[cfg(all(test, unix))]
+impl Pty {
+    /// Whether the program reads keys one by one, as a line editor does.
+    pub(crate) fn reads_keys(&self) -> bool {
+        use rustix_openpty::rustix::termios::{LocalModes, tcgetattr};
+        let modes = tcgetattr(&self.master).expect("the pty's modes");
+        !modes.local_modes.contains(LocalModes::ICANON)
+    }
+}
+
 impl Drop for Pty {
     fn drop(&mut self) {
         if self.notifier.0.send(Msg::Shutdown).is_err() {

src/term/shell/tests.rs

@@ -108,7 +108,9 @@ impl Run {
         }
     }
 
-    fn send(&self, line: &str) {
+    /// Types `line` at a prompt, once its line editor reads raw keys.
+    fn send(&mut self, line: &str) {
+        self.until("line editor", |run| run.pty.reads_keys());
         self.pty.write(format!("{line}\r").into_bytes());
     }
 
@@ -131,9 +133,9 @@ impl Run {
     /// The prompt's folder, the script loaded by `probe`, then a cd into the inner folder.
     fn walk(&mut self, probe: &str) {
         let start = self.start.clone();
+        self.send(probe);
         self.until("first folder", |run| run.folders.contains(&start));
         assert_eq!(self.folders[0], start);
-        self.send(probe);
         self.until("loaded script", |run| run.shows("ELY-LOADED"));
         self.send("cd in*");
         let inner = start.join(INNER);

src/term/unix.rs

@@ -44,6 +44,12 @@ impl Pty {
     pub fn id(&self) -> u32 {
         self.child.id()
     }
+
+    /// A copy of the master, for tests to read its modes.
+    #[cfg(test)]
+    pub fn master(&self) -> io::Result<File> {
+        self.file.try_clone()
+    }
 }
 
 /// Starts `program`, or the login shell, in `cwd` on a new pty of `size`.