1 files changed, 129 insertions, 0 deletions
diff --git a/src/plugin_command.rs b/src/plugin_command.rs
new file mode 100644
index 00000000..ba0a1422
--- /dev/null
+++ b/src/plugin_command.rs
@@ -0,0 +1,129 @@
+#[cfg(any(windows, test))]
+use std::path::Path;
+#[cfg(windows)]
+use std::path::PathBuf;
+use std::process::Command;
+
+pub(crate) fn command_for_argv(program: &str, args: &[String]) -> Command {
+    let mut command = command_for_program(program);
+    command.args(args);
+    command
+}
+
+#[cfg(not(windows))]
+fn command_for_program(program: &str) -> Command {
+    Command::new(program)
+}
+
+#[cfg(windows)]
+fn command_for_program(program: &str) -> Command {
+    let resolved = resolve_windows_program(program);
+    let command_program = resolved.as_ref().map_or_else(
+        || std::ffi::OsString::from(program),
+        |path| path.as_os_str().to_os_string(),
+    );
+    if is_windows_batch_file_name(program)
+        || resolved
+            .as_ref()
+            .is_some_and(|path| is_windows_batch_path(path))
+    {
+        let shell =
+            std::env::var_os("ComSpec").unwrap_or_else(|| r"C:\Windows\System32\cmd.exe".into());
+        let mut command = Command::new(shell);
+        command.arg("/d").arg("/c").arg(command_program);
+        command
+    } else {
+        Command::new(command_program)
+    }
+}
+
+#[cfg(windows)]
+fn resolve_windows_program(program: &str) -> Option<PathBuf> {
+    if has_path_separator(program) {
+        return None;
+    }
+    let path = Path::new(program);
+    if path.extension().is_some() {
+        return std::env::var_os("PATH").and_then(|path_var| {
+            std::env::split_paths(&path_var)
+                .map(|dir| dir.join(program))
+                .find(|candidate| candidate.is_file())
+        });
+    }
+    let extensions = windows_path_extensions();
+    std::env::var_os("PATH").and_then(|path_var| {
+        std::env::split_paths(&path_var).find_map(|dir| {
+            extensions
+                .iter()
+                .map(|extension| dir.join(format!("{program}{extension}")))
+                .find(|candidate| candidate.is_file())
+        })
+    })
+}
+
+#[cfg(windows)]
+fn windows_path_extensions() -> Vec<String> {
+    std::env::var_os("PATHEXT")
+        .map(|value| {
+            value
+                .to_string_lossy()
+                .split(';')
+                .map(str::trim)
+                .filter(|part| !part.is_empty())
+                .map(|part| {
+                    if part.starts_with('.') {
+                        part.to_string()
+                    } else {
+                        format!(".{part}")
+                    }
+                })
+                .collect::<Vec<_>>()
+        })
+        .filter(|extensions| !extensions.is_empty())
+        .unwrap_or_else(|| {
+            vec![
+                ".COM".to_string(),
+                ".EXE".to_string(),
+                ".BAT".to_string(),
+                ".CMD".to_string(),
+            ]
+        })
+}
+
+#[cfg(windows)]
+fn has_path_separator(program: &str) -> bool {
+    program.contains(['/', '\\'])
+}
+
+#[cfg(windows)]
+fn is_windows_batch_path(path: &Path) -> bool {
+    path.extension()
+        .and_then(std::ffi::OsStr::to_str)
+        .is_some_and(is_windows_batch_extension)
+}
+
+#[cfg(any(windows, test))]
+fn is_windows_batch_file_name(program: &str) -> bool {
+    Path::new(program)
+        .extension()
+        .and_then(std::ffi::OsStr::to_str)
+        .is_some_and(is_windows_batch_extension)
+}
+
+#[cfg(any(windows, test))]
+fn is_windows_batch_extension(extension: &str) -> bool {
+    extension.eq_ignore_ascii_case("cmd") || extension.eq_ignore_ascii_case("bat")
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn recognizes_windows_batch_extensions_case_insensitively() {
+        assert!(is_windows_batch_file_name("npm.cmd"));
+        assert!(is_windows_batch_file_name("script.BAT"));
+        assert!(!is_windows_batch_file_name("node.exe"));
+        assert!(!is_windows_batch_file_name("node"));
+    }
+}