fix(shell): Make sidecars work in tests (fix #13767) (#3234)

.changes/make-sidecars-work-in-tests.md

@@ -0,0 +1,6 @@
+---
+'shell': 'patch:bug'
+'shell-js': 'patch:bug'
+---
+
+Make sidecars work in tests. Executable resolution is aware of the "deps" directory.

plugins/shell/src/process/mod.rs

@@ -118,27 +118,38 @@ pub struct Output {
 }
 
 fn relative_command_path(command: &Path) -> crate::Result<PathBuf> {
-    match platform::current_exe()?.parent() {
+    let exe_path = platform::current_exe()?;
+
+    let exe_dir = exe_path
+        .parent()
+        .ok_or(crate::Error::CurrentExeHasNoParent)?;
+
+    // If a test is being run, the executable is in the "deps" directory, so we need to go up one level.
+    let base_dir = if exe_dir.ends_with("deps") {
+        exe_dir.parent().unwrap_or(exe_dir)
+    } else {
+        exe_dir
+    };
+
+    let mut command_path = base_dir.join(command);
+
     #[cfg(windows)]
-        Some(exe_dir) => {
-            let mut command_path = exe_dir.join(command);
+    {
         let already_exe = command_path.extension().is_some_and(|ext| ext == "exe");
         if !already_exe {
             // do not use with_extension to retain dots in the command filename
             command_path.as_mut_os_string().push(".exe");
         }
-            Ok(command_path)
     }
+
     #[cfg(not(windows))]
-        Some(exe_dir) => {
-            let mut command_path = exe_dir.join(command);
+    {
         if command_path.extension().is_some_and(|ext| ext == "exe") {
             command_path.set_extension("");
         }
+    }
+
     Ok(command_path)
-        }
-        None => Err(crate::Error::CurrentExeHasNoParent),
-    }
 }
 
 impl From<Command> for StdCommand {
@@ -508,6 +519,8 @@ mod tests {
             .unwrap()
             .parent()
             .unwrap()
+            .parent() // Go up once more to get out of the "deps" directory
+            .unwrap()
             .to_owned();
         assert_eq!(
             relative_command_path(Path::new("Tauri.Example")).unwrap(),