Rename tui_app_server to tui (#16104)

This is a follow-up to https://github.com/openai/codex/pull/15922. That
previous PR deleted the old `tui` directory and left the new
`tui_app_server` directory in place. This PR renames `tui_app_server` to
`tui` and fixes up all references.

codex-rs/tui/src/exec_command.rs

@@ -0,0 +1,107 @@
+use std::path::Path;
+use std::path::PathBuf;
+
+use codex_shell_command::parse_command::extract_shell_command;
+use dirs::home_dir;
+use shlex::try_join;
+
+pub(crate) fn escape_command(command: &[String]) -> String {
+    try_join(command.iter().map(String::as_str)).unwrap_or_else(|_| command.join(" "))
+}
+
+pub(crate) fn strip_bash_lc_and_escape(command: &[String]) -> String {
+    if let Some((_, script)) = extract_shell_command(command) {
+        return script.to_string();
+    }
+    escape_command(command)
+}
+
+pub(crate) fn split_command_string(command: &str) -> Vec<String> {
+    let Some(parts) = shlex::split(command) else {
+        return vec![command.to_string()];
+    };
+    match shlex::try_join(parts.iter().map(String::as_str)) {
+        Ok(round_trip)
+            if round_trip == command
+                || (!command.contains(":\\")
+                    && shlex::split(&round_trip).as_ref() == Some(&parts)) =>
+        {
+            parts
+        }
+        _ => vec![command.to_string()],
+    }
+}
+
+/// If `path` is absolute and inside $HOME, return the part *after* the home
+/// directory; otherwise, return the path as-is. Note if `path` is the homedir,
+/// this will return and empty path.
+pub(crate) fn relativize_to_home<P>(path: P) -> Option<PathBuf>
+where
+    P: AsRef<Path>,
+{
+    let path = path.as_ref();
+    if !path.is_absolute() {
+        // If the path is not absolute, we can’t do anything with it.
+        return None;
+    }
+
+    let home_dir = home_dir()?;
+    let rel = path.strip_prefix(&home_dir).ok()?;
+    Some(rel.to_path_buf())
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_escape_command() {
+        let args = vec!["foo".into(), "bar baz".into(), "weird&stuff".into()];
+        let cmdline = escape_command(&args);
+        assert_eq!(cmdline, "foo 'bar baz' 'weird&stuff'");
+    }
+
+    #[test]
+    fn test_strip_bash_lc_and_escape() {
+        // Test bash
+        let args = vec!["bash".into(), "-lc".into(), "echo hello".into()];
+        let cmdline = strip_bash_lc_and_escape(&args);
+        assert_eq!(cmdline, "echo hello");
+
+        // Test zsh
+        let args = vec!["zsh".into(), "-lc".into(), "echo hello".into()];
+        let cmdline = strip_bash_lc_and_escape(&args);
+        assert_eq!(cmdline, "echo hello");
+
+        // Test absolute path to zsh
+        let args = vec!["/usr/bin/zsh".into(), "-lc".into(), "echo hello".into()];
+        let cmdline = strip_bash_lc_and_escape(&args);
+        assert_eq!(cmdline, "echo hello");
+
+        // Test absolute path to bash
+        let args = vec!["/bin/bash".into(), "-lc".into(), "echo hello".into()];
+        let cmdline = strip_bash_lc_and_escape(&args);
+        assert_eq!(cmdline, "echo hello");
+    }
+
+    #[test]
+    fn split_command_string_round_trips_shell_wrappers() {
+        let command =
+            shlex::try_join(["/bin/zsh", "-lc", r#"python3 -c 'print("Hello, world!")'"#])
+                .expect("round-trippable command");
+        assert_eq!(
+            split_command_string(&command),
+            vec![
+                "/bin/zsh".to_string(),
+                "-lc".to_string(),
+                r#"python3 -c 'print("Hello, world!")'"#.to_string(),
+            ]
+        );
+    }
+
+    #[test]
+    fn split_command_string_preserves_non_roundtrippable_windows_commands() {
+        let command = r#"C:\Program Files\Git\bin\bash.exe -lc "echo hi""#;
+        assert_eq!(split_command_string(command), vec![command.to_string()]);
+    }
+}