[codex] refine shell prompt and powershell invocation

crates/tui/src/eval.rs

@@ -15,7 +15,7 @@ use std::process::Command;
 use std::time::{Duration, Instant};
 use tempfile::TempDir;
 
-use crate::shell_invocation::{ShellInvocation, shell_invocation};
+use crate::shell_invocation::{ShellInvocation, shell_invocation, shell_program_stem};
 #[cfg(test)]
 use crate::shell_invocation::{ShellPlatform, ShellProbe, shell_invocation_for_platform};
 
@@ -36,8 +36,9 @@ fn push_eval_shell_args(cmd: &mut Command, invocation: &ShellInvocation) {
     #[cfg(windows)]
     {
         use std::os::windows::process::CommandExt;
+        let is_cmd = shell_program_stem(&invocation.program).is_some_and(|stem| stem == "cmd");
         if invocation.raw_payload_on_windows
-            && invocation.program.eq_ignore_ascii_case("cmd")
+            && is_cmd
             && invocation.args.len() == 2
             && invocation.args[0].eq_ignore_ascii_case("/C")
         {
@@ -805,6 +806,7 @@ mod tests {
             powershell.args,
             vec![
                 "-NoProfile".to_string(),
+                "-NonInteractive".to_string(),
                 "-Command".to_string(),
                 command.to_string()
             ]
@@ -820,4 +822,26 @@ mod tests {
         assert_eq!(unix.args, vec!["-c".to_string(), command.to_string()]);
         assert!(!unix.raw_payload_on_windows);
     }
+
+    #[cfg(windows)]
+    #[test]
+    fn push_eval_shell_args_uses_raw_arg_for_full_path_cmd() {
+        let invocation = ShellInvocation {
+            program: r"C:\Windows\System32\cmd.exe".to_string(),
+            args: vec![
+                "/C".to_string(),
+                r#"chcp 65001 >NUL & git commit -m "quoted""#.to_string(),
+            ],
+            raw_payload_on_windows: true,
+        };
+
+        let mut cmd = Command::new("cmd");
+        push_eval_shell_args(&mut cmd, &invocation);
+        let got: Vec<String> = cmd
+            .get_args()
+            .map(|arg| arg.to_string_lossy().into_owned())
+            .collect();
+
+        assert_eq!(got, invocation.args);
+    }
 }

crates/tui/src/prompts.rs

@@ -9,6 +9,7 @@
 
 use crate::models::SystemPrompt;
 use crate::project_context::{ProjectContext, load_project_context_with_parents};
+use crate::shell_invocation::{shell_invocation, shell_program_stem};
 use crate::tui::app::AppMode;
 use crate::tui::approval::ApprovalMode;
 use std::path::{Path, PathBuf};
@@ -143,7 +144,8 @@ fn render_environment_block(workspace: &Path, locale_tag: &str) -> String {
     let deepseek_version = env!("CARGO_PKG_VERSION");
     let platform = std::env::consts::OS;
     let shell = if cfg!(windows) {
-        crate::shell_invocation::shell_invocation("").program
+        let resolved = shell_invocation("").program;
+        shell_program_stem(&resolved).unwrap_or(resolved)
     } else {
         std::env::var("SHELL").unwrap_or_else(|_| "unknown".to_string())
     };
@@ -1074,6 +1076,18 @@ mod tests {
         assert!(block.contains(&format!("- pwd: {}", tmp.path().display())));
         assert!(block.contains("- platform:"));
         assert!(block.contains("- shell:"));
+
+        #[cfg(windows)]
+        {
+            let shell_line = block
+                .lines()
+                .find(|line| line.starts_with("- shell: "))
+                .expect("shell line present");
+            assert!(
+                !shell_line.contains('\\') && !shell_line.contains('/'),
+                "Windows prompt shell should use the stem, not a full path"
+            );
+        }
     }
 
     #[test]

crates/tui/src/shell_invocation.rs

@@ -75,7 +75,6 @@ pub(crate) struct ShellProbe {
     pub(crate) shell: Option<String>,
     pub(crate) comspec: Option<String>,
     pub(crate) pwsh_on_path: bool,
-    pub(crate) powershell_on_path: bool,
 }
 
 impl ShellProbe {
@@ -89,7 +88,6 @@ impl ShellProbe {
                 .ok()
                 .filter(|value| !value.trim().is_empty()),
             pwsh_on_path: command_on_path("pwsh.exe") || command_on_path("pwsh"),
-            powershell_on_path: command_on_path("powershell.exe") || command_on_path("powershell"),
         }
     }
 }
@@ -128,14 +126,13 @@ fn windows_shell_invocation(command: &str, probe: &ShellProbe) -> ShellInvocatio
         return shell;
     }
 
+    // Default Windows resolution is intentionally pwsh.exe -> cmd.exe. Windows
+    // PowerShell 5.x can still be selected explicitly through SHELL, but it is
+    // not used as an implicit fallback.
     if probe.pwsh_on_path {
         return powershell_invocation("pwsh.exe", command);
     }
 
-    if probe.powershell_on_path {
-        return powershell_invocation("powershell.exe", command);
-    }
-
     if let Some(comspec) = probe
         .comspec
         .as_deref()
@@ -173,6 +170,7 @@ fn powershell_invocation(program: &str, command: &str) -> ShellInvocation {
         program: program.to_string(),
         args: vec![
             "-NoProfile".to_string(),
+            "-NonInteractive".to_string(),
             "-Command".to_string(),
             command.to_string(),
         ],
@@ -196,17 +194,14 @@ fn windows_posix_shell_program<'a>(shell: &'a str, stem: &'a str) -> &'a str {
     }
 }
 
-fn shell_program_stem(program: &str) -> Option<String> {
+pub(crate) fn shell_program_stem(program: &str) -> Option<String> {
     let normalized = program.trim().replace('\\', "/");
-    let filename = normalized.rsplit('/').next()?.trim();
-    let stem = filename
-        .strip_suffix(".exe")
-        .or_else(|| filename.strip_suffix(".EXE"))
-        .unwrap_or(filename);
+    let filename = normalized.rsplit('/').next()?.trim().to_ascii_lowercase();
+    let stem = filename.strip_suffix(".exe").unwrap_or(&filename);
     if stem.is_empty() {
         None
     } else {
-        Some(stem.to_ascii_lowercase())
+        Some(stem.to_string())
     }
 }
 
@@ -266,6 +261,7 @@ mod tests {
             invocation.args,
             [
                 "-NoProfile",
+                "-NonInteractive",
                 "-Command",
                 r#"Remove-Item -Path "target file.txt" -Force"#
             ]
@@ -277,6 +273,35 @@ mod tests {
         );
     }
 
+    #[test]
+    fn windows_shell_env_can_select_windows_powershell() {
+        let invocation = shell_invocation_for_platform(
+            "Get-ChildItem",
+            ShellPlatform::Windows,
+            &ShellProbe {
+                shell: Some(
+                    r"C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe".to_string(),
+                ),
+                comspec: Some(r"C:\Windows\System32\cmd.exe".to_string()),
+                pwsh_on_path: false,
+            },
+        );
+
+        assert_eq!(
+            invocation.program,
+            r"C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe"
+        );
+        assert_eq!(
+            invocation.args,
+            ["-NoProfile", "-NonInteractive", "-Command", "Get-ChildItem"]
+        );
+        assert!(!invocation.raw_payload_on_windows);
+        assert_eq!(
+            invocation.display_command().as_deref(),
+            Some("Get-ChildItem")
+        );
+    }
+
     #[test]
     fn windows_uses_pwsh_before_cmd_when_available() {
         let invocation = shell_invocation_for_platform(
@@ -290,30 +315,60 @@ mod tests {
         );
 
         assert_eq!(invocation.program, "pwsh.exe");
-        assert_eq!(invocation.args, ["-NoProfile", "-Command", "Get-ChildItem"]);
+        assert_eq!(
+            invocation.args,
+            ["-NoProfile", "-NonInteractive", "-Command", "Get-ChildItem"]
+        );
         assert!(!invocation.raw_payload_on_windows);
     }
 
+    #[test]
+    fn windows_without_pwsh_falls_straight_to_cmd_not_windows_powershell() {
+        let invocation = shell_invocation_for_platform(
+            "git status --short",
+            ShellPlatform::Windows,
+            &ShellProbe {
+                comspec: Some(
+                    r"C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe".to_string(),
+                ),
+                pwsh_on_path: false,
+                ..probe()
+            },
+        );
+
+        assert_eq!(invocation.program, "cmd");
+        assert_eq!(
+            invocation.args,
+            ["/C", "chcp 65001 >NUL & git status --short"]
+        );
+        assert!(invocation.raw_payload_on_windows);
+        assert_eq!(
+            invocation.display_command().as_deref(),
+            Some("git status --short")
+        );
+    }
+
     #[test]
     fn windows_falls_back_to_comspec_cmd_with_utf8_prefix() {
         let invocation = shell_invocation_for_platform(
-            r#"git commit -m "hello world""#,
+            "git status --short",
             ShellPlatform::Windows,
             &ShellProbe {
                 comspec: Some(r"C:\Windows\System32\cmd.exe".to_string()),
+                pwsh_on_path: false,
                 ..probe()
             },
         );
 
         assert_eq!(invocation.program, r"C:\Windows\System32\cmd.exe");
         assert_eq!(
             invocation.args,
-            ["/C", r#"chcp 65001 >NUL & git commit -m "hello world""#]
+            ["/C", "chcp 65001 >NUL & git status --short"]
         );
         assert!(invocation.raw_payload_on_windows);
         assert_eq!(
             invocation.display_command().as_deref(),
-            Some(r#"git commit -m "hello world""#)
+            Some("git status --short")
         );
     }