diff --git a/tests/frontend/managers/downloadManager.routingOverride.test.js b/tests/frontend/managers/downloadManager.routingOverride.test.js
new file mode 100644
index 00000000..a354e609
--- /dev/null
+++ b/tests/frontend/managers/downloadManager.routingOverride.test.js
@@ -0,0 +1,209 @@
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';
+
+const {
+ DOWNLOAD_MANAGER_MODULE,
+ MODAL_MANAGER_MODULE,
+ UI_HELPERS_MODULE,
+ STATE_MODULE,
+ LOADING_MANAGER_MODULE,
+ API_FACTORY_MODULE,
+ STORAGE_HELPERS_MODULE,
+ FOLDER_TREE_MANAGER_MODULE,
+ I18N_HELPERS_MODULE,
+ SUMMARY_MODULE,
+ OTHER_MODELS_MODULE,
+} = vi.hoisted(() => ({
+ DOWNLOAD_MANAGER_MODULE: new URL('../../../static/js/managers/DownloadManager.js', import.meta.url).pathname,
+ MODAL_MANAGER_MODULE: new URL('../../../static/js/managers/ModalManager.js', import.meta.url).pathname,
+ UI_HELPERS_MODULE: new URL('../../../static/js/utils/uiHelpers.js', import.meta.url).pathname,
+ STATE_MODULE: new URL('../../../static/js/state/index.js', import.meta.url).pathname,
+ LOADING_MANAGER_MODULE: new URL('../../../static/js/managers/LoadingManager.js', import.meta.url).pathname,
+ API_FACTORY_MODULE: new URL('../../../static/js/api/modelApiFactory.js', import.meta.url).pathname,
+ STORAGE_HELPERS_MODULE: new URL('../../../static/js/utils/storageHelpers.js', import.meta.url).pathname,
+ FOLDER_TREE_MANAGER_MODULE: new URL('../../../static/js/components/FolderTreeManager.js', import.meta.url).pathname,
+ I18N_HELPERS_MODULE: new URL('../../../static/js/utils/i18nHelpers.js', import.meta.url).pathname,
+ SUMMARY_MODULE: new URL('../../../static/js/components/DownloadBatchSummaryModal.js', import.meta.url).pathname,
+ OTHER_MODELS_MODULE: new URL('../../../static/js/utils/otherModels.js', import.meta.url).pathname,
+}));
+
+vi.mock(MODAL_MANAGER_MODULE, () => ({
+ modalManager: { showModal: vi.fn(), closeModal: vi.fn() },
+}));
+vi.mock(UI_HELPERS_MODULE, () => ({
+ showToast: vi.fn(),
+ showActionToast: vi.fn(),
+ setupAutoNewlineOnPaste: vi.fn(),
+}));
+vi.mock(STATE_MODULE, () => ({
+ state: { global: { settings: {} }, loadingManager: {} },
+}));
+vi.mock(LOADING_MANAGER_MODULE, () => ({
+ LoadingManager: vi.fn(() => ({})),
+}));
+vi.mock(API_FACTORY_MODULE, () => ({
+ getModelApiClient: vi.fn(),
+ resetAndReload: vi.fn(),
+}));
+vi.mock(STORAGE_HELPERS_MODULE, () => ({
+ getStorageItem: vi.fn((_key, defaultValue) => defaultValue),
+ setStorageItem: vi.fn(),
+}));
+vi.mock(FOLDER_TREE_MANAGER_MODULE, () => ({
+ FolderTreeManager: vi.fn(() => ({})),
+}));
+vi.mock(I18N_HELPERS_MODULE, () => ({
+ translate: vi.fn((_key, _vars, fallback) => fallback ?? ''),
+}));
+vi.mock(SUMMARY_MODULE, () => ({
+ showDownloadBatchSummary: vi.fn(),
+}));
+vi.mock(OTHER_MODELS_MODULE, () => ({
+ enableOtherModels: vi.fn(),
+ openOtherModelsSettings: vi.fn(),
+}));
+
+const { DownloadManager } = await import(DOWNLOAD_MANAGER_MODULE);
+const { state } = await import(STATE_MODULE);
+const { setStorageItem } = await import(STORAGE_HELPERS_MODULE);
+
+describe('DownloadManager checkpoint/diffusion routing override', () => {
+ let manager;
+
+ function setupDom() {
+ document.body.innerHTML = `
+
+
+
+
+
+
+
+
+
+
+ `;
+ }
+
+ function createManager(modelType, displayName = 'Model') {
+ manager = new DownloadManager();
+ manager.apiClient = {
+ modelType,
+ apiConfig: { config: { displayName } },
+ fetchModelRoots: vi.fn(),
+ };
+ manager.selectedFile = null;
+ manager.selectedFiles = [];
+ manager.currentVersion = null;
+ manager.initializeFolderTree = vi.fn().mockResolvedValue();
+ manager.folderTreeManager = { init: vi.fn(), getSelectedPath: vi.fn(() => '') };
+ manager.loadDefaultPathSetting = vi.fn();
+ vi.spyOn(manager, '_resolveOtherSubType').mockResolvedValue(null);
+ }
+
+ beforeEach(() => {
+ setupDom();
+ state.global.settings = {};
+ vi.clearAllMocks();
+ });
+
+ afterEach(() => {
+ vi.unstubAllGlobals();
+ });
+
+ it('shows the toggle for diffusion-routed checkpoints and marks diffusion active', async () => {
+ createManager('checkpoints', 'Checkpoint');
+ vi.spyOn(manager, '_resolveIsDiffusionModel').mockResolvedValue(true);
+ manager.apiClient.fetchModelRoots.mockResolvedValue({
+ success: true,
+ roots: ['/models/unet'],
+ });
+ state.global.settings.default_unet_root = '/models/unet';
+
+ await manager.proceedToLocationContent();
+
+ const group = document.getElementById('routingOverrideGroup');
+ expect(group.style.display).not.toBe('none');
+ const [checkpointBtn, diffusionBtn] = group.querySelectorAll('.routing-override-option');
+ expect(diffusionBtn.classList.contains('active')).toBe(true);
+ expect(diffusionBtn.getAttribute('aria-pressed')).toBe('true');
+ expect(checkpointBtn.classList.contains('active')).toBe(false);
+ expect(manager.apiClient.fetchModelRoots).toHaveBeenCalledWith('diffusion_model');
+ expect(document.getElementById('modelRoot').value).toBe('/models/unet');
+ });
+
+ it('keeps the toggle hidden on non-checkpoints pages', async () => {
+ createManager('loras', 'LoRA');
+ manager.apiClient.fetchModelRoots.mockResolvedValue({
+ success: true,
+ roots: ['/models/loras'],
+ });
+
+ await manager.proceedToLocationContent();
+
+ expect(document.getElementById('routingOverrideGroup').style.display).toBe('none');
+ expect(manager.apiClient.fetchModelRoots).toHaveBeenCalledWith();
+ });
+
+ it('re-fetches diffusion roots and preselects the unet default when overriding to diffusion', async () => {
+ createManager('checkpoints', 'Checkpoint');
+ vi.spyOn(manager, '_resolveIsDiffusionModel').mockResolvedValue(false);
+ manager.apiClient.fetchModelRoots
+ .mockResolvedValueOnce({ success: true, roots: ['/models/checkpoints'] })
+ .mockResolvedValueOnce({ success: true, roots: ['/models/unet'] });
+ state.global.settings.default_unet_root = '/models/unet';
+
+ await manager.proceedToLocationContent();
+ expect(document.getElementById('modelRoot').value).toBe('/models/checkpoints');
+
+ await manager.handleRoutingOverrideChange(true);
+
+ expect(manager.apiClient.fetchModelRoots).toHaveBeenLastCalledWith('diffusion_model');
+ const modelRoot = document.getElementById('modelRoot');
+ expect(Array.from(modelRoot.options).map(o => o.value)).toEqual(['/models/unet']);
+ expect(modelRoot.value).toBe('/models/unet');
+ const group = document.getElementById('routingOverrideGroup');
+ const [checkpointBtn, diffusionBtn] = group.querySelectorAll('.routing-override-option');
+ expect(checkpointBtn.classList.contains('active')).toBe(false);
+ expect(diffusionBtn.classList.contains('active')).toBe(true);
+ });
+
+ it('turns off Use Default Path for the session without persisting when overriding', async () => {
+ createManager('checkpoints', 'Checkpoint');
+ vi.spyOn(manager, '_resolveIsDiffusionModel').mockResolvedValue(false);
+ manager.apiClient.fetchModelRoots.mockResolvedValue({
+ success: true,
+ roots: ['/models/checkpoints'],
+ });
+
+ await manager.proceedToLocationContent();
+
+ manager.useDefaultPath = true;
+ document.getElementById('useDefaultPath').checked = true;
+
+ await manager.handleRoutingOverrideChange(true);
+
+ expect(manager.useDefaultPath).toBe(false);
+ expect(document.getElementById('useDefaultPath').checked).toBe(false);
+ expect(setStorageItem).not.toHaveBeenCalled();
+ });
+
+ it('clears the override when switching back to the auto-classified side', async () => {
+ createManager('checkpoints', 'Checkpoint');
+ vi.spyOn(manager, '_resolveIsDiffusionModel').mockResolvedValue(false);
+ manager.apiClient.fetchModelRoots.mockResolvedValue({
+ success: true,
+ roots: ['/models/checkpoints'],
+ });
+
+ await manager.proceedToLocationContent();
+ await manager.handleRoutingOverrideChange(true);
+ expect(manager._routingOverride).toBe(true);
+
+ manager.apiClient.fetchModelRoots.mockClear();
+ await manager.handleRoutingOverrideChange(false);
+
+ expect(manager._routingOverride).toBeNull();
+ // Back on the checkpoint group: no routing argument
+ expect(manager.apiClient.fetchModelRoots).toHaveBeenCalledWith();
+ });
+});