RCC setup: Fix crash if no plans for current session are configured

Long path support is always enabled in the current session. If no plans
for the current session were configured, attempting to enable long path
support crashed because the directory for the stdio files was missing.

CMK-18570

src/bin/scheduler/setup/general.rs

@@ -93,10 +93,32 @@ fn setup_rcc_working_directories(
         &environment_building_working_directory(working_directory),
         rcc_plans,
     );
+
+    #[cfg(unix)]
     let (mut surviving_plans, rcc_setup_failures) = setup_with_one_directory_per_user(
         &rcc_setup_working_directory(working_directory),
         surviving_plans,
     );
+    #[cfg(windows)]
+    let (mut surviving_plans, rcc_setup_failures) = {
+        let (surviving_plans, rcc_setup_failures) = setup_with_one_directory_per_user(
+            &rcc_setup_working_directory(working_directory),
+            surviving_plans,
+        );
+        let (surviving_plans, rcc_setup_failures_long_path_support) =
+            setup_with_one_directory_for_current_session(
+                &rcc_setup_working_directory(working_directory),
+                surviving_plans,
+            );
+        (
+            surviving_plans,
+            rcc_setup_failures
+                .into_iter()
+                .chain(rcc_setup_failures_long_path_support)
+                .collect::<HashMap<String, String>>(),
+        )
+    };
+
     surviving_plans.extend(system_plans);
     (
         surviving_plans,
@@ -156,6 +178,27 @@ fn setup_with_one_directory_per_user(
     (surviving_plans, failures)
 }
 
+#[cfg(windows)]
+fn setup_with_one_directory_for_current_session(
+    target: &Utf8Path,
+    plans: Vec<Plan>,
+) -> (Vec<Plan>, HashMap<String, String>) {
+    use robotmk::session::CurrentSession;
+
+    match create_dir_all(target.join(CurrentSession {}.id())) {
+        Ok(()) => (plans, HashMap::new()),
+        Err(error) => {
+            let error = anyhow!(error).context(format!("Failed to create directory {target}",));
+            info!("{error:#}");
+            let mut failures = HashMap::new();
+            for plan in plans {
+                failures.insert(plan.id.clone(), format!("{error:#}"));
+            }
+            (vec![], failures)
+        }
+    }
+}
+
 fn setup_results_directories(global_config: &GlobalConfig, plans: &[Plan]) -> AnyhowResult<()> {
     create_dir_all(&global_config.results_directory)
         .context("Failed to create results directory")?;