fix: support custom command keybindings on windows

refs #1041

8 files changed, 193 insertions, 7 deletions

diff --git a/src/app/input/navigate.rs b/src/app/input/navigate.rs
index b278daac..f4719ace 100644
--- a/src/app/input/navigate.rs
+++ b/src/app/input/navigate.rs
@@ -1,7 +1,7 @@
 use std::{
     fs, io,
     io::Write,
-    process::{Command, Stdio},
+    process::Stdio,
     time::{SystemTime, UNIX_EPOCH},
 };
 
@@ -771,10 +771,8 @@ impl App {
         &self,
         binding: &crate::config::CustomCommandKeybind,
     ) -> std::io::Result<()> {
-        let mut command = Command::new("/bin/sh");
+        let mut command = crate::platform::detached_custom_command_process(&binding.command);
         command
-            .arg("-lc")
-            .arg(&binding.command)
             .stdin(Stdio::null())
             .stdout(Stdio::null())
             .stderr(Stdio::null());
diff --git a/src/main.rs b/src/main.rs
index 04ff4894..3b4bed1c 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -220,6 +220,7 @@ const DEFAULT_CONFIG: &str = r##"# herdr configuration
 # Custom commands use the same binding syntax.
 # type = "shell" runs detached in the background.
 # type = "pane" opens a temporary pane and closes it when the command exits.
+# On Windows, command strings run through cmd.exe /d /c.
 # [[keys.command]]
 # key = "prefix+alt+g"
 # type = "pane"
diff --git a/src/pane.rs b/src/pane.rs
index 6094af83..a6edaaa7 100644
--- a/src/pane.rs
+++ b/src/pane.rs
@@ -1585,9 +1585,7 @@ impl PaneRuntime {
         render_notify: Arc<Notify>,
         render_dirty: Arc<AtomicBool>,
     ) -> std::io::Result<Self> {
-        let mut cmd = CommandBuilder::new("/bin/sh");
-        cmd.arg("-c");
-        cmd.arg(command);
+        let mut cmd = crate::platform::pane_custom_command_pty_builder(command);
         cmd.cwd(cwd);
         apply_pane_terminal_env(&mut cmd);
         apply_pane_launch_env(&mut cmd, launch_env);
diff --git a/src/platform/fallback.rs b/src/platform/fallback.rs
index e9134a8b..382ccf5e 100644
--- a/src/platform/fallback.rs
+++ b/src/platform/fallback.rs
@@ -6,6 +6,23 @@ use super::{ClipboardImage, ForegroundJob, Signal};
 /// Unsupported platform stub.
 pub fn raise_server_nofile_limit() {}
 
+fn raw_command_argv(command: &str, flag: &str) -> Vec<std::ffi::OsString> {
+    vec!["/bin/sh".into(), flag.into(), command.into()]
+}
+
+pub(crate) fn detached_custom_command_process_platform(command: &str) -> std::process::Command {
+    let argv = raw_command_argv(command, "-lc");
+    let mut command = std::process::Command::new(&argv[0]);
+    command.args(&argv[1..]);
+    command
+}
+
+pub(crate) fn pane_custom_command_pty_builder_platform(
+    command: &str,
+) -> portable_pty::CommandBuilder {
+    portable_pty::CommandBuilder::from_argv(raw_command_argv(command, "-c"))
+}
+
 /// Unsupported platform stub.
 pub(crate) fn scrollback_editor_argv(_path: &std::path::Path) -> std::io::Result<Vec<String>> {
     Err(std::io::Error::new(
diff --git a/src/platform/linux.rs b/src/platform/linux.rs
index 4e5574d0..be0c97b9 100644
--- a/src/platform/linux.rs
+++ b/src/platform/linux.rs
@@ -39,6 +39,23 @@ static FOREGROUND_MEMBERS_CACHE: Mutex<ForegroundMembersCache> =
 
 pub fn raise_server_nofile_limit() {}
 
+fn raw_command_argv(command: &str, flag: &str) -> Vec<std::ffi::OsString> {
+    vec!["/bin/sh".into(), flag.into(), command.into()]
+}
+
+pub(crate) fn detached_custom_command_process_platform(command: &str) -> std::process::Command {
+    let argv = raw_command_argv(command, "-lc");
+    let mut command = std::process::Command::new(&argv[0]);
+    command.args(&argv[1..]);
+    command
+}
+
+pub(crate) fn pane_custom_command_pty_builder_platform(
+    command: &str,
+) -> portable_pty::CommandBuilder {
+    portable_pty::CommandBuilder::from_argv(raw_command_argv(command, "-c"))
+}
+
 pub(crate) fn scrollback_editor_argv(path: &std::path::Path) -> std::io::Result<Vec<String>> {
     let quoted_path = shell_quote(&path.display().to_string());
     let command = format!(
diff --git a/src/platform/macos.rs b/src/platform/macos.rs
index e72d32fe..f2441f06 100644
--- a/src/platform/macos.rs
+++ b/src/platform/macos.rs
@@ -16,6 +16,23 @@ const PROC_PGRP_ONLY: u32 = 2;
 const SERVER_NOFILE_LIMIT_TARGET: libc::rlim_t = 8192;
 const CF_STRING_ENCODING_UTF8: u32 = 0x0800_0100;
 
+fn raw_command_argv(command: &str, flag: &str) -> Vec<std::ffi::OsString> {
+    vec!["/bin/sh".into(), flag.into(), command.into()]
+}
+
+pub(crate) fn detached_custom_command_process_platform(command: &str) -> std::process::Command {
+    let argv = raw_command_argv(command, "-lc");
+    let mut command = std::process::Command::new(&argv[0]);
+    command.args(&argv[1..]);
+    command
+}
+
+pub(crate) fn pane_custom_command_pty_builder_platform(
+    command: &str,
+) -> portable_pty::CommandBuilder {
+    portable_pty::CommandBuilder::from_argv(raw_command_argv(command, "-c"))
+}
+
 pub(crate) fn scrollback_editor_argv(path: &Path) -> std::io::Result<Vec<String>> {
     let quoted_path = shell_quote(&path.display().to_string());
     let command = format!(
diff --git a/src/platform/mod.rs b/src/platform/mod.rs
index 889c4ce9..e396966b 100644
--- a/src/platform/mod.rs
+++ b/src/platform/mod.rs
@@ -25,6 +25,14 @@ pub enum Signal {
     Kill,
 }
 
+pub(crate) fn detached_custom_command_process(command: &str) -> std::process::Command {
+    detached_custom_command_process_platform(command)
+}
+
+pub(crate) fn pane_custom_command_pty_builder(command: &str) -> portable_pty::CommandBuilder {
+    pane_custom_command_pty_builder_platform(command)
+}
+
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub(crate) struct PlatformCapabilities {
     pub(crate) live_handoff: bool,
@@ -199,6 +207,29 @@ mod tests {
     use super::*;
 
     #[test]
+    fn detached_custom_command_preserves_unix_login_shell_flag() {
+        let cmd = detached_custom_command_process("echo hello");
+        assert_eq!(cmd.get_program(), std::ffi::OsStr::new("/bin/sh"));
+        assert_eq!(
+            cmd.get_args().collect::<Vec<_>>(),
+            [
+                std::ffi::OsStr::new("-lc"),
+                std::ffi::OsStr::new("echo hello")
+            ]
+        );
+    }
+
+    #[test]
+    fn pane_custom_command_builder_preserves_unix_shell_flag() {
+        let expected: Vec<std::ffi::OsString> =
+            vec!["/bin/sh".into(), "-c".into(), "echo hello".into()];
+        assert_eq!(
+            pane_custom_command_pty_builder("echo hello").get_argv(),
+            &expected
+        );
+    }
+
+    #[test]
     fn read_limited_reader_returns_complete_data_under_limit() {
         let input = std::io::Cursor::new(b"image".to_vec());
         assert_eq!(
diff --git a/src/platform/windows.rs b/src/platform/windows.rs
index 50e0e905..cc486ace 100644
--- a/src/platform/windows.rs
+++ b/src/platform/windows.rs
@@ -46,6 +46,44 @@ struct WindowsProcessEntry {
 
 pub fn raise_server_nofile_limit() {}
 
+fn raw_command_shell(comspec: Option<std::ffi::OsString>) -> std::ffi::OsString {
+    comspec
+        .filter(|value| !value.is_empty())
+        .unwrap_or_else(|| r"C:\Windows\System32\cmd.exe".into())
+}
+
+pub(crate) fn detached_custom_command_process_platform(command: &str) -> std::process::Command {
+    detached_custom_command_process_with_comspec(command, std::env::var_os("ComSpec"))
+}
+
+fn detached_custom_command_process_with_comspec(
+    command: &str,
+    comspec: Option<std::ffi::OsString>,
+) -> std::process::Command {
+    use std::os::windows::process::CommandExt;
+
+    let mut process = std::process::Command::new(raw_command_shell(comspec));
+    process.arg("/d").arg("/c").raw_arg(command);
+    process
+}
+
+pub(crate) fn pane_custom_command_pty_builder_platform(
+    command: &str,
+) -> portable_pty::CommandBuilder {
+    pane_custom_command_pty_builder_with_comspec(command, std::env::var_os("ComSpec"))
+}
+
+fn pane_custom_command_pty_builder_with_comspec(
+    command: &str,
+    comspec: Option<std::ffi::OsString>,
+) -> portable_pty::CommandBuilder {
+    let mut builder = portable_pty::CommandBuilder::new(raw_command_shell(comspec));
+    builder.arg("/d");
+    builder.arg("/c");
+    builder.raw_arg(command);
+    builder
+}
+
 pub(crate) fn scrollback_editor_argv(path: &std::path::Path) -> std::io::Result<Vec<String>> {
     let editor = std::env::var("VISUAL")
         .ok()
@@ -537,6 +575,75 @@ mod tests {
         time::{Duration, Instant},
     };
 
+    fn argv_strings(argv: &[std::ffi::OsString]) -> Vec<String> {
+        argv.into_iter()
+            .map(|arg| arg.to_string_lossy().into_owned())
+            .collect()
+    }
+
+    #[test]
+    fn pane_custom_command_uses_cmd() {
+        let builder = super::pane_custom_command_pty_builder_with_comspec(
+            "echo hello",
+            Some(r"C:\Windows\System32\cmd.exe".into()),
+        );
+
+        assert_eq!(
+            argv_strings(builder.get_argv()),
+            [r"C:\Windows\System32\cmd.exe", "/d", "/c"]
+        );
+    }
+
+    #[test]
+    fn detached_custom_command_uses_cmd() {
+        let expected_shell = std::env::var_os("ComSpec")
+            .filter(|value| !value.is_empty())
+            .unwrap_or_else(|| r"C:\Windows\System32\cmd.exe".into())
+            .to_string_lossy()
+            .into_owned();
+
+        let process = super::detached_custom_command_process_platform("echo hello");
+
+        assert_eq!(process.get_program().to_string_lossy(), expected_shell);
+        assert_eq!(
+            process
+                .get_args()
+                .map(|arg| arg.to_string_lossy().into_owned())
+                .collect::<Vec<_>>(),
+            ["/d", "/c", "echo hello"]
+        );
+    }
+
+    #[test]
+    fn custom_command_falls_back_when_comspec_is_empty() {
+        let builder =
+            super::pane_custom_command_pty_builder_with_comspec("echo hello", Some("".into()));
+
+        assert_eq!(
+            argv_strings(builder.get_argv()),
+            [r"C:\Windows\System32\cmd.exe", "/d", "/c"]
+        );
+    }
+
+    #[test]
+    fn detached_custom_command_preserves_quoted_command_tail() {
+        let path = std::env::temp_dir().join(format!(
+            "herdr-raw-command-quotes-{}.txt",
+            std::process::id()
+        ));
+        let command = format!(r#"echo "hi" > "{}""#, path.display());
+
+        let status = super::detached_custom_command_process_platform(&command)
+            .status()
+            .expect("spawn raw command");
+
+        assert!(status.success(), "{status:?}");
+        let content = std::fs::read_to_string(&path).expect("read command output");
+        let _ = std::fs::remove_file(&path);
+        assert!(content.contains(r#""hi""#), "{content:?}");
+        assert!(!content.contains(r#"\"hi\""#), "{content:?}");
+    }
+
     #[test]
     fn windows_process_cwd_reads_child_launch_directory() {
         let cwd = std::env::temp_dir().join(format!("herdr-cwd-test-{}", std::process::id()));