fix(kvs): make unit tests pass on QNX targets

score/kvs/kvs_test.cpp

@@ -18,6 +18,8 @@
 #include "score/os/stat.h"
 #include "score/utility.hpp"
 
+#include <unistd.h>
+
 TEST(kvs_constructor, move_constructor)
 {
     const std::uint32_t instance_b = 5;
@@ -1919,6 +1921,12 @@ TEST(kvs_flush, flush_failure_mutex)
 
 TEST(kvs_flush, flush_failure_rotate_snapshots)
 {
+    // Root ignores file permissions, so flush would succeed.
+    if (geteuid() == 0)
+    {
+        GTEST_SKIP() << "File permissions are not enforced for root.";
+    }
+
     prepare_environment();
     // Test folder for permission handling.
     std::string permissions_dir = data_dir + "permissions/";
@@ -1936,7 +1944,7 @@ TEST(kvs_flush, flush_failure_rotate_snapshots)
         permissions_dir, std::filesystem::perms::owner_read, std::filesystem::perm_options::replace);
     auto flush_result = result.value().flush();
 
-    EXPECT_FALSE(flush_result);
+    ASSERT_FALSE(flush_result);
     EXPECT_EQ(static_cast<ErrorCode>(*flush_result.error()), ErrorCode::PhysicalStorageFailure);
 
     cleanup_environment();

score/kvs/rust_kvs/json_backend.rs

@@ -999,9 +999,9 @@ mod error_code_tests {
 
 #[cfg(test)]
 mod json_backend_builder_tests {
+    use crate::test_utils::tempdir;
     use crate::{json_backend::JsonBackendBuilder, prelude::KvsBackend};
     use std::path::PathBuf;
-    use tempfile::tempdir;
 
     #[test]
     fn test_new_ok() {
@@ -1086,9 +1086,9 @@ mod json_backend_tests {
     use crate::json_backend::{JsonBackend, JsonBackendBuilder};
     use crate::kvs_api::{InstanceId, SnapshotId, KVS_MAX_KEY_LENGTH_BYTES};
     use crate::kvs_value::{KvsMap, KvsValue};
+    use crate::test_utils::tempdir;
     use std::os::unix::fs::PermissionsExt;
     use std::path::{Path, PathBuf};
-    use tempfile::tempdir;
 
     /// Expected permissions of KVS JSON and hash files: 0640.
     const EXPECTED_FILE_MODE: u32 = 0o640;
@@ -1525,10 +1525,10 @@ mod kvs_backend_tests {
     use crate::kvs_api::{InstanceId, SnapshotId};
     use crate::kvs_backend::KvsBackend;
     use crate::kvs_value::{KvsMap, KvsValue};
+    use crate::test_utils::tempdir;
     use std::fs;
     use std::os::unix::fs::PermissionsExt;
     use std::path::Path;
-    use tempfile::tempdir;
 
     /// Expected permissions of KVS JSON and hash files: 0640.
     const EXPECTED_FILE_MODE: u32 = 0o640;

score/kvs/rust_kvs/kvs.rs

@@ -334,8 +334,8 @@ mod kvs_tests {
     use crate::kvs_builder::KvsData;
     use crate::kvs_value::{KvsMap, KvsValue};
     use crate::log::ScoreDebug;
+    use crate::test_utils::tempdir;
     use std::sync::{Arc, Mutex};
-    use tempfile::tempdir;
 
     /// Most tests can be performed with mocked backend.
     /// Only those with file handling must use concrete implementation.

score/kvs/rust_kvs/kvs_builder.rs

@@ -322,10 +322,10 @@ mod kvs_builder_tests {
     use crate::kvs_api::{InstanceId, KvsApi, KvsDefaults, KvsLoad, SnapshotId};
     use crate::kvs_builder::{KvsBuilder, KVS_MAX_INSTANCES, KVS_POOL};
     use crate::kvs_value::{KvsMap, KvsValue};
+    use crate::test_utils::tempdir;
     use core::ops::DerefMut;
     use std::path::{Path, PathBuf};
     use std::sync::{LazyLock, Mutex, MutexGuard};
-    use tempfile::tempdir;
 
     /// Serial test execution mutex.
     static SERIAL_TEST: LazyLock<Mutex<()>> = LazyLock::new(|| Mutex::new(()));

score/kvs/rust_kvs/lib.rs

@@ -142,6 +142,8 @@ pub mod kvs_mock;
 pub mod kvs_serialize;
 pub mod kvs_value;
 mod log;
+#[cfg(test)]
+mod test_utils;
 
 /// Prelude module for convenient imports
 pub mod prelude {

score/kvs/rust_kvs/test_utils.rs

@@ -0,0 +1,25 @@
+// *******************************************************************************
+// Copyright (c) 2026 Contributors to the Eclipse Foundation
+//
+// See the NOTICE file(s) distributed with this work for additional
+// information regarding copyright ownership.
+//
+// This program and the accompanying materials are made available under the
+// terms of the Apache License Version 2.0 which is available at
+// <https://www.apache.org/licenses/LICENSE-2.0>
+//
+// SPDX-License-Identifier: Apache-2.0
+// *******************************************************************************
+
+//! Helpers shared by unit tests.
+
+/// Create a temporary directory for a test.
+/// On QNX, `/tmp` can't hold directories.
+/// The test's working directory can, so the directory is created there.
+pub fn tempdir() -> std::io::Result<tempfile::TempDir> {
+    if cfg!(target_os = "nto") {
+        tempfile::tempdir_in(".")
+    } else {
+        tempfile::tempdir()
+    }
+}