3 files changed, 70 insertions, 8 deletions

diff --git a/src/pane.rs b/src/pane.rs
index 4ac86c23..ec1b8646 100644
--- a/src/pane.rs
+++ b/src/pane.rs
@@ -2009,7 +2009,7 @@ impl PaneRuntime {
         let windows_powershell_prompt_cwd_reporting =
             uses_windows_powershell_pane_shell(shell_config);
         let mut cmd = pane_shell_command_builder(shell_config)?;
-        cmd.cwd(cwd);
+        cmd.cwd(crate::platform::normalize_cwd_for_launch(&cwd));
         apply_pane_terminal_env(&mut cmd);
         apply_pane_launch_env(&mut cmd, launch_env);
         Self::spawn_command_builder(
@@ -2051,7 +2051,7 @@ impl PaneRuntime {
         render_dirty: Arc<RenderSignal>,
     ) -> std::io::Result<Self> {
         let mut cmd = crate::platform::pane_custom_command_pty_builder(command);
-        cmd.cwd(cwd);
+        cmd.cwd(crate::platform::normalize_cwd_for_launch(&cwd));
         apply_pane_terminal_env(&mut cmd);
         apply_pane_launch_env(&mut cmd, launch_env);
         Self::spawn_command_builder(
@@ -2098,7 +2098,7 @@ impl PaneRuntime {
         for arg in args {
             cmd.arg(arg);
         }
-        cmd.cwd(cwd);
+        cmd.cwd(crate::platform::normalize_cwd_for_launch(&cwd));
         apply_pane_terminal_env(&mut cmd);
         apply_pane_launch_env(&mut cmd, launch_env);
         Self::spawn_command_builder(
diff --git a/src/platform/mod.rs b/src/platform/mod.rs
index a578b42d..70047fef 100644
--- a/src/platform/mod.rs
+++ b/src/platform/mod.rs
@@ -82,6 +82,15 @@ pub(crate) fn plugin_runtime_path(path: &std::path::Path) -> std::path::PathBuf
     plugin_runtime_path_platform(path)
 }
 
+pub(crate) fn normalize_cwd_for_launch(path: &std::path::Path) -> std::path::PathBuf {
+    normalize_cwd_for_launch_platform(path)
+}
+
+#[cfg(not(windows))]
+fn normalize_cwd_for_launch_platform(path: &std::path::Path) -> std::path::PathBuf {
+    path.to_path_buf()
+}
+
 #[cfg(not(windows))]
 fn plugin_runtime_path_platform(path: &std::path::Path) -> std::path::PathBuf {
     path.to_path_buf()
diff --git a/src/platform/windows.rs b/src/platform/windows.rs
index 080bbf34..9742b52c 100644
--- a/src/platform/windows.rs
+++ b/src/platform/windows.rs
@@ -380,6 +380,54 @@ pub(crate) fn prepare_paste_text_for_pty_platform(text: String) -> String {
     text.replace("\r\n", "\n").replace('\n', "\r\n")
 }
 
+pub(crate) fn normalize_cwd_for_launch_platform(path: &std::path::Path) -> PathBuf {
+    use std::os::windows::ffi::{OsStrExt, OsStringExt};
+    use std::path::{Component, Prefix};
+    use windows_sys::Win32::{
+        Foundation::INVALID_HANDLE_VALUE,
+        Storage::FileSystem::{FindClose, FindFirstFileW, WIN32_FIND_DATAW},
+    };
+
+    fn stored_name(path: &std::path::Path) -> Option<std::ffi::OsString> {
+        let input = path
+            .as_os_str()
+            .encode_wide()
+            .chain(std::iter::once(0))
+            .collect::<Vec<_>>();
+        let mut data = std::mem::MaybeUninit::<WIN32_FIND_DATAW>::uninit();
+        let handle = unsafe { FindFirstFileW(input.as_ptr(), data.as_mut_ptr()) };
+        if handle == INVALID_HANDLE_VALUE {
+            return None;
+        }
+        let data = unsafe { data.assume_init() };
+        unsafe { FindClose(handle) };
+        let len = data
+            .cFileName
+            .iter()
+            .position(|&ch| ch == 0)
+            .unwrap_or(data.cFileName.len());
+        Some(std::ffi::OsString::from_wide(&data.cFileName[..len]))
+    }
+
+    let mut normalized = PathBuf::new();
+    for component in path.components() {
+        match component {
+            Component::Prefix(prefix) => match prefix.kind() {
+                Prefix::Disk(drive) => {
+                    normalized.push(format!("{}:", char::from(drive).to_ascii_uppercase()))
+                }
+                _ => normalized.push(prefix.as_os_str()),
+            },
+            Component::Normal(name) => {
+                let candidate = normalized.join(name);
+                normalized.push(stored_name(&candidate).unwrap_or_else(|| name.to_os_string()));
+            }
+            _ => normalized.push(component.as_os_str()),
+        }
+    }
+    normalized
+}
+
 pub(crate) fn plugin_runtime_path_platform(path: &std::path::Path) -> PathBuf {
     use std::os::windows::ffi::OsStrExt;
 
@@ -3399,15 +3447,17 @@ mod tests {
     }
 
     #[test]
-    fn windows_process_cwd_reads_child_launch_directory() {
-        let cwd = std::env::temp_dir().join(format!("herdr-cwd-test-{}", std::process::id()));
+    fn windows_process_cwd_reads_normalized_child_launch_directory() {
+        let name = format!("Herdr-Cwd-Case-{}", std::process::id());
+        let cwd = std::env::temp_dir().join(&name);
         fs::create_dir_all(&cwd).expect("create cwd fixture");
+        let launch_cwd = cwd.with_file_name(name.to_ascii_lowercase());
 
         let shell =
             std::env::var_os("ComSpec").unwrap_or_else(|| r"C:\Windows\System32\cmd.exe".into());
         let mut child = Command::new(shell)
             .args(["/D", "/Q", "/C", "ping -n 11 127.0.0.1 > NUL"])
-            .current_dir(&cwd)
+            .current_dir(super::normalize_cwd_for_launch_platform(&launch_cwd))
             .stdin(Stdio::null())
             .stdout(Stdio::null())
             .stderr(Stdio::null())
@@ -3418,7 +3468,7 @@ mod tests {
         let mut observed = None;
         while Instant::now() < deadline {
             observed = super::process_cwd(child.id());
-            if observed.as_deref() == Some(cwd.as_path()) {
+            if observed.as_ref().and_then(|path| path.file_name()) == Some(name.as_ref()) {
                 break;
             }
             thread::sleep(Duration::from_millis(100));
@@ -3428,7 +3478,10 @@ mod tests {
         let _ = child.wait();
         let _ = fs::remove_dir_all(&cwd);
 
-        assert_eq!(observed.as_deref(), Some(cwd.as_path()));
+        assert_eq!(
+            observed.as_ref().and_then(|path| path.file_name()),
+            Some(name.as_ref())
+        );
     }
 
     #[test]