test(e2e_ui): cover files-panel collapsed-state persistence across reload

Signed-off-by: dbczumar <corey.zumar@databricks.com>

ap-web/src/lib/filesPanelPreferences.test.ts

@@ -20,10 +20,8 @@ describe("filesPanelPreferences", () => {
   });
 
   it("round-trips a written preference", () => {
-    writeFilesPanelPreferences({ changedOnly: true });
-    // The written value must come back — proves the write serialized and the
-    // read parsed/validated the field.
-    expect(readFilesPanelPreferences()).toEqual({ changedOnly: true });
+    writeFilesPanelPreferences({ changedOnly: true, collapsed: false });
+    expect(readFilesPanelPreferences()).toEqual({ changedOnly: true, collapsed: false });
   });
 
   it("falls back to defaults on malformed JSON", () => {
@@ -43,6 +41,6 @@ describe("filesPanelPreferences", () => {
     // A record present but with a non-boolean changedOnly must default the
     // field rather than pass a garbage value through to the panel.
     localStorage.setItem(STORAGE_KEY, JSON.stringify({ changedOnly: "yes" }));
-    expect(readFilesPanelPreferences()).toEqual({ changedOnly: false });
+    expect(readFilesPanelPreferences()).toEqual({ changedOnly: false, collapsed: false });
   });
 });

ap-web/src/lib/filesPanelPreferences.ts

@@ -16,6 +16,8 @@
 export interface FilesPanelPreferences {
   /** true = changed-files-only flat list, false = full folder tree ("All"). */
   changedOnly: boolean;
+  /** true = the panel header is collapsed (content hidden). */
+  collapsed: boolean;
 }
 
 const STORAGE_KEY = "omnigent:files-panel-preferences";
@@ -24,6 +26,7 @@ const STORAGE_KEY = "omnigent:files-panel-preferences";
 // the working folder, not just the changed subset.
 export const DEFAULT_FILES_PANEL_PREFERENCES: FilesPanelPreferences = {
   changedOnly: false,
+  collapsed: false,
 };
 
 /**
@@ -46,6 +49,8 @@ export function readFilesPanelPreferences(): FilesPanelPreferences {
         typeof p.changedOnly === "boolean"
           ? p.changedOnly
           : DEFAULT_FILES_PANEL_PREFERENCES.changedOnly,
+      collapsed:
+        typeof p.collapsed === "boolean" ? p.collapsed : DEFAULT_FILES_PANEL_PREFERENCES.collapsed,
     };
   } catch {
     return DEFAULT_FILES_PANEL_PREFERENCES;

ap-web/src/shell/AppShell.test.tsx

@@ -2083,7 +2083,9 @@ describe("Files scope default and persistence", () => {
     fireEvent.click(screen.getByRole("button", { name: /files: switch to changed/i }));
     expect(screen.getByTestId("files-panel")).toHaveAttribute("data-flat-view", "true");
     // The choice was written to localStorage — that's what makes it sticky.
-    expect(localStorage.getItem(PREF_KEY)).toBe(JSON.stringify({ changedOnly: true }));
+    expect(localStorage.getItem(PREF_KEY)).toBe(
+      JSON.stringify({ changedOnly: true, collapsed: false }),
+    );
 
     // Re-enter a *different* session fresh: it must open on the remembered
     // "Changed" scope. cleanup() unmounts the shell but does NOT touch

ap-web/src/shell/AppShell.tsx

@@ -623,7 +623,7 @@ export function AppShell() {
   const handleFilesFlatViewChange = useCallback((v: boolean) => {
     filesPanelScopePrefRef.current = v;
     setFilesPanelFlatView(v);
-    writeFilesPanelPreferences({ changedOnly: v });
+    writeFilesPanelPreferences({ ...readFilesPanelPreferences(), changedOnly: v });
   }, []);
 
   const openFileViewer = useCallback(

ap-web/src/shell/FilesPanel.tsx

@@ -20,6 +20,7 @@ import {
   useWorkspaceFileSearch,
 } from "@/hooks/useWorkspaceChangedFiles";
 import { cn } from "@/lib/utils";
+import { readFilesPanelPreferences, writeFilesPanelPreferences } from "@/lib/filesPanelPreferences";
 import { Tooltip, TooltipContent, TooltipProvider, TooltipTrigger } from "@/components/ui/tooltip";
 import {
   DropdownMenu,
@@ -287,7 +288,7 @@ export function FilesPanel({
   const runnerWentOffline = useChatStore(
     (s) => s.conversationId === conversationId && s.sessionStatus === "failed",
   );
-  const [collapsed, setCollapsed] = useState(false);
+  const [collapsed, setCollapsed] = useState(() => readFilesPanelPreferences().collapsed);
   const [changedSearch, setChangedSearch] = useState("");
   const [treeSearch, setTreeSearch] = useState("");
   const [debouncedTreeSearch, setDebouncedTreeSearch] = useState("");
@@ -389,7 +390,13 @@ export function FilesPanel({
             <button
               type="button"
               className="flex min-w-0 flex-1 cursor-pointer items-center gap-2 text-left"
-              onClick={() => setCollapsed((v) => !v)}
+              onClick={() =>
+                setCollapsed((v) => {
+                  const next = !v;
+                  writeFilesPanelPreferences({ ...readFilesPanelPreferences(), collapsed: next });
+                  return next;
+                })
+              }
               aria-expanded={!collapsed}
             >
               <span className="shrink-0 font-medium text-sm">Working folder</span>

tests/e2e_ui/files/test_reload_persistence.py

@@ -1,4 +1,4 @@
-"""E2E: file-viewer and comment state survive a full browser reload.
+"""E2E: file-viewer, comment, and files-panel state survive a full browser reload.
 
 These tests prove the durability path that the AppShell unit tests can
 only approximate: ``AppShell.test.tsx`` mocks ``FileViewer`` and asserts
@@ -25,6 +25,8 @@ import httpx
 import pytest
 from playwright.sync_api import Page, expect
 
+from tests.e2e_ui.conftest import open_right_rail
+
 # The agent spec uses ``os_env.cwd: .`` (see ``_TEST_AGENT_YAML`` in
 # conftest), so filesystem PUTs land in ``<repo-root>/<session_id>/``
 # next to the spawned server. Clean that per-session dir up in teardown
@@ -181,3 +183,42 @@ def test_comment_persists_across_reload(
     ).json()
     assert len(comments) == 1, f"Expected exactly 1 persisted comment, got {comments}"
     assert comments[0]["body"] == _COMMENT_BODY
+
+
+def test_files_panel_collapsed_state_persists_across_reload(
+    page: Page,
+    seeded_session: tuple[str, str],
+) -> None:
+    """Collapse the Working-folder panel, reload, and assert it stays collapsed.
+
+    Unlike the file-viewer/comment cases above (server-persisted, URL-
+    rehydrated), the panel's collapsed state lives in a single app-global
+    localStorage key with no per-conversation keying — the same preference
+    the panel reads to carry the choice across *sessions*. A cold reload is
+    the strongest single-session proxy for that: it re-mounts ``FilesPanel``,
+    whose initial collapsed state is seeded purely from the stored
+    preference (``readFilesPanelPreferences().collapsed``). A failure after
+    reload means the choice wasn't persisted, the durability path the
+    AppShell unit test can only approximate with a mocked store.
+    """
+    base_url, session_id = seeded_session
+    page.goto(f"{base_url}/c/{session_id}")
+    open_right_rail(page)
+
+    # The Working-folder header doubles as the collapse toggle; ``aria-expanded``
+    # tracks the panel's collapsed state and starts expanded by default.
+    rail = page.get_by_role("complementary", name="Workspace")
+    header = rail.get_by_role("button", name=re.compile("Working folder"))
+    expect(header).to_have_attribute("aria-expanded", "true", timeout=30_000)
+
+    header.click()
+    expect(header).to_have_attribute("aria-expanded", "false")
+
+    page.reload()
+    open_right_rail(page)
+
+    # A cold reload must restore the collapsed choice from localStorage.
+    header_after = page.get_by_role("complementary", name="Workspace").get_by_role(
+        "button", name=re.compile("Working folder")
+    )
+    expect(header_after).to_have_attribute("aria-expanded", "false", timeout=30_000)