Prompt History and PR Pane -> Primary

apps/desktop/src/renderer/components/chat/AgentChatMessageList.test.tsx

@@ -84,7 +84,7 @@ import {
   collapseChatTranscriptEvents,
   groupConsecutiveWorkLogRows,
 } from "./chatTranscriptRows";
-import { ChatPrPaneInsetContext } from "./chatPrPaneInset";
+import { promptHistoryEventKey } from "./chatPromptHistory";
 import { resetFilesWorkspaceCacheForTests } from "./chatWorkspacePaths";
 import { mixedIdToolActivityBoundaryEvents } from "../../../shared/testFixtures/chatToolActivity";
 
@@ -137,6 +137,7 @@ function renderMessageList(
     onRunUnprocessedMessage?: (event: Extract<AgentChatEventEnvelope["event"], { type: "user_message" }>) => void | Promise<void>;
     onRestoreCancelledQueue?: (recoveryId: string) => Promise<boolean>;
     scrollToRowKeyRequest?: { key: string; requestId: number } | null;
+    scrollToPromptHistoryRequest?: { eventKey: string; requestId: number } | null;
     hasOlderHistory?: boolean;
     loadingOlderHistory?: boolean;
     olderHistoryError?: string | null;
@@ -165,6 +166,7 @@ function renderMessageList(
         onRunUnprocessedMessage={options?.onRunUnprocessedMessage}
         onRestoreCancelledQueue={options?.onRestoreCancelledQueue}
         scrollToRowKeyRequest={options?.scrollToRowKeyRequest}
+        scrollToPromptHistoryRequest={options?.scrollToPromptHistoryRequest}
         hasOlderHistory={options?.hasOlderHistory}
         loadingOlderHistory={options?.loadingOlderHistory}
         olderHistoryError={options?.olderHistoryError}
@@ -200,20 +202,6 @@ const transcriptProofArtifact: ComputerUseArtifactView = {
   reviewNote: null,
 };
 
-/** The message list under a floating PR pane publishing `prPaneBottomViewportPx`. */
-function renderMessageListUnderPrPane(
-  events: AgentChatEventEnvelope[],
-  prPaneBottomViewportPx: number | null,
-) {
-  return render(
-    <MemoryRouter initialEntries={[{ pathname: "/" }]}>
-      <ChatPrPaneInsetContext.Provider value={prPaneBottomViewportPx}>
-        <AgentChatMessageList events={events} />
-      </ChatPrPaneInsetContext.Provider>
-    </MemoryRouter>,
-  );
-}
-
 function makeRect(box: { top?: number; left?: number; width?: number; height?: number }): DOMRect {
   const top = box.top ?? 0;
   const left = box.left ?? 0;
@@ -235,25 +223,22 @@ function makeRect(box: { top?: number; left?: number; width?: number; height?: n
 /**
  * jsdom has no layout, so every box measures 0×0: the minimap rail decides it
  * is inert and `resolveMinimapIndexFromPointer` returns null for every pointer
- * Y. Stub the two boxes the rail actually reads — the list root it is
- * positioned against, and its own hit strip.
+ * Y. Stub the two boxes the rail actually reads — the list root and its own
+ * hit strip.
  */
 function stubMinimapLayout(options?: {
   listWidth?: number;
   listHeight?: number;
-  /** Viewport-space top edge of the list root — the frame the PR pane converts into. */
-  listTop?: number;
   railTop?: number;
   railHeight?: number;
 }): { railTop: number; railHeight: number } {
   const listWidth = options?.listWidth ?? 960;
   const listHeight = options?.listHeight ?? 600;
-  const listTop = options?.listTop ?? 0;
   const railTop = options?.railTop ?? 100;
   const railHeight = options?.railHeight ?? 400;
   vi.spyOn(Element.prototype, "getBoundingClientRect").mockImplementation(function (this: Element) {
     if (this.hasAttribute("data-chat-message-list-root")) {
-      return makeRect({ width: listWidth, height: listHeight, top: listTop });
+      return makeRect({ width: listWidth, height: listHeight });
     }
     if (this.tagName === "BUTTON" && this.closest("[data-testid='chat-user-minimap']")) {
       return makeRect({ top: railTop, height: railHeight, width: 24 });
@@ -2021,22 +2006,11 @@ describe("AgentChatMessageList transcript rendering", () => {
     expect(transcript.scrollTop).toBe(0);
   });
 
-  it("insets the rail by the PR pane's rect delta, not by its height", () => {
-    // REGRESSION: the floating PR pane is positioned against the chat surface
-    // while the rail is positioned against the message-list root, which sits
-    // 200px lower (chat header + sync hairline). Converting a published HEIGHT
-    // with the pane's `top-3` constant would read 12 + 240 + 12 = 264 here and
-    // push the rail a whole header below where it belongs.
-    stubMinimapLayout({ listTop: 200 });
-    renderMessageListUnderPrPane(MINIMAP_TRANSCRIPT, 300);
-
-    // 300 (pane bottom) - 200 (list root top) + 12 (gap).
-    expect(screen.getByTestId("chat-user-minimap").style.top).toBe("112px");
-  });
-
-  it("drops the rail inset entirely when no PR pane is floating", () => {
-    stubMinimapLayout({ listTop: 200 });
-    renderMessageListUnderPrPane(MINIMAP_TRANSCRIPT, null);
+  it("keeps the rail anchored when a PR pane is floating", () => {
+    // The PR pane is an overlay. Its presence must not move the transcript's
+    // history markers down into the space below the card.
+    stubMinimapLayout();
+    renderMessageList(MINIMAP_TRANSCRIPT);
 
     expect(screen.getByTestId("chat-user-minimap").style.top).toBe("0px");
   });
@@ -2326,6 +2300,28 @@ describe("AgentChatMessageList transcript rendering", () => {
     expect(transcript.scrollTop).toBe(0);
   });
 
+  it("scrolls to the prompt selected by composer history", () => {
+    const view = renderMessageList(MINIMAP_TRANSCRIPT);
+    const transcript = document.querySelector(".ade-chat-timeline-pane") as HTMLDivElement;
+    Object.defineProperty(transcript, "scrollHeight", { configurable: true, value: 1_000 });
+    Object.defineProperty(transcript, "clientHeight", { configurable: true, value: 200 });
+
+    const target = MINIMAP_TRANSCRIPT[2]!;
+    if (target.event.type !== "user_message") throw new Error("test target must be a user message");
+    const request = {
+      eventKey: promptHistoryEventKey({ timestamp: target.timestamp, event: target.event }),
+      requestId: 1,
+    };
+    view.rerender(
+      <MemoryRouter initialEntries={[{ pathname: "/" }]}>
+        <AgentChatMessageList events={MINIMAP_TRANSCRIPT} scrollToPromptHistoryRequest={request} />
+        <LocationProbe />
+      </MemoryRouter>,
+    );
+
+    expect(transcript.scrollTop).toBeGreaterThan(0);
+  });
+
   // "absorbs tool summaries" test removed: tested old ChatWorkLogBlock
   // summary absorption rendering which changes with UI iterations.
 

apps/desktop/src/renderer/components/chat/AgentChatMessageList.tsx

@@ -121,6 +121,7 @@ import { BackgroundJobLine, SubagentResultCard, SubagentSpawnCard, SubagentStopp
 import { AdeCard } from "./AdeCard";
 import { navigateToSpawnedChat } from "./spawnNavigation";
 import { ChatUserMinimap } from "./ChatUserMinimap";
+import { promptHistoryEventKey } from "./chatPromptHistory";
 import { AgentCliAuthCard, type AgentCliAuthCardInfo } from "./AgentCliAuthCard";
 import { ChatContinuityRecoveryCard } from "./ChatContinuityRecoveryCard";
 import { classifyProviderFailure, ProviderFailureRecoveryCard } from "./ProviderFailureRecoveryCard";
@@ -5230,6 +5231,7 @@ function AgentChatMessageListMain({
   onReturnToLatest,
   mosaic,
   scrollToRowKeyRequest,
+  scrollToPromptHistoryRequest,
   proofArtifacts = [],
   allowLocalProofArtifactProtocol = false,
   onOpenProofDrawer,
@@ -5280,6 +5282,8 @@ function AgentChatMessageListMain({
   mosaic?: MosaicRenderContext;
   /** Imperative jump request used by the while-you-were-away wake digest. */
   scrollToRowKeyRequest?: { key: string; requestId: number } | null;
+  /** Imperative jump request emitted when composer history selects a prompt. */
+  scrollToPromptHistoryRequest?: { eventKey: string; requestId: number } | null;
   /** Intentional proof linked to this chat, rendered at the transcript tail. */
   proofArtifacts?: ComputerUseArtifactView[];
   /** Local Electron can stream larger artifacts through its range protocol. */
@@ -5294,6 +5298,7 @@ function AgentChatMessageListMain({
   const contentWrapperRef = useRef<HTMLDivElement | null>(null);
   const olderHistorySentinelRef = useRef<HTMLDivElement | null>(null);
   const lastHandledScrollToRowRequestIdRef = useRef<number | null>(null);
+  const lastHandledPromptHistoryRequestIdRef = useRef<number | null>(null);
   const location = useLocation();
   const navigate = useNavigate();
   // Carries the CollapseTranscriptContext alongside events/rows so appended
@@ -5330,11 +5335,9 @@ function AgentChatMessageListMain({
     restoredScrollMemory?.wasPinnedToBottom === false ? (restoredScrollMemory.lastSeenRowKey ?? null) : null,
   );
   // Measured geometry the minimap rail needs. Kept as two pieces of state so a
-  // width-only change (pane resize) and a height-only change don't invalidate
-  // each other. `top` is viewport-space: it is what converts the floating PR
-  // pane's published bottom edge into the rail's own coordinate frame.
-  const [listRootBoxPx, setListRootBoxPx] = useState<{ width: number; height: number; top: number }>(
-    { width: 0, height: 0, top: 0 },
+  // width-only change and a height-only change don't invalidate each other.
+  const [listRootBoxPx, setListRootBoxPx] = useState<{ width: number; height: number }>(
+    { width: 0, height: 0 },
   );
   const [columnWidthPx, setColumnWidthPx] = useState(0);
   // Track the single pending rAF handle for scroll-to-bottom writes so we
@@ -5787,12 +5790,10 @@ function AgentChatMessageListMain({
     const rect = el.getBoundingClientRect();
     const width = Math.max(el.clientWidth, rect.width);
     const height = Math.max(el.clientHeight, rect.height);
-    const top = rect.top;
     setListRootBoxPx((current) => (
       movedByAPixel(current.width, width)
         || movedByAPixel(current.height, height)
-        || movedByAPixel(current.top, top)
-        ? { width, height, top }
+        ? { width, height }
         : current
     ));
   }, []);
@@ -6012,6 +6013,17 @@ function AgentChatMessageListMain({
     scrollToRowKey(scrollToRowKeyRequest.key);
   }, [scrollToRowKey, scrollToRowKeyRequest]);
 
+  useEffect(() => {
+    if (!scrollToPromptHistoryRequest?.eventKey) return;
+    if (lastHandledPromptHistoryRequestIdRef.current === scrollToPromptHistoryRequest.requestId) return;
+    lastHandledPromptHistoryRequestIdRef.current = scrollToPromptHistoryRequest.requestId;
+    const rowIndex = groupedRows.findIndex((row) => (
+      row.event.type === "user_message"
+      && promptHistoryEventKey({ timestamp: row.timestamp, event: row.event }) === scrollToPromptHistoryRequest.eventKey
+    ));
+    if (rowIndex >= 0) scrollToRowIndexNearTop(rowIndex);
+  }, [groupedRows, scrollToPromptHistoryRequest, scrollToRowIndexNearTop]);
+
   const scheduleAnchoredRowCorrection = useCallback((rowKey: string) => {
     if (anchorCorrectionRafRef.current !== null) {
       cancelAnimationFrame(anchorCorrectionRafRef.current);
@@ -6440,6 +6452,17 @@ function AgentChatMessageListMain({
     [groupedRows],
   );
 
+  const promptHistoryFocusIndex = useMemo(() => {
+    if (!scrollToPromptHistoryRequest?.eventKey) return null;
+    const rowIndex = groupedRows.findIndex((row) => (
+      row.event.type === "user_message"
+      && promptHistoryEventKey({ timestamp: row.timestamp, event: row.event }) === scrollToPromptHistoryRequest.eventKey
+    ));
+    if (rowIndex < 0) return null;
+    const minimapIndex = minimapSourceEntries.findIndex((entry) => entry.rowIndex === rowIndex);
+    return minimapIndex >= 0 ? minimapIndex : null;
+  }, [groupedRows, minimapSourceEntries, scrollToPromptHistoryRequest]);
+
   const rowStartOffsetsForMinimap = useMemo(() => {
     void measurementTick;
     return computeRowStartOffsets(groupedRows.length, rowHeight, timelineRowGapPx);
@@ -6693,9 +6716,8 @@ function AgentChatMessageListMain({
       {/* Direct child of the list root on purpose: the rail's `left-0` and all of
           its gutter maths assume the offset parent is the element whose width is
           `listWidthPx`. An intermediate max-width wrapper would silently shift
-          the rail into the message column. The PR pane's edge is NOT passed —
-          the rail reads it from context (see chatPrPaneInset.ts) and subtracts
-          the list-root top measured here to land in its own frame. */}
+          the rail into the message column. Floating panes stay independent of
+          this fixed transcript anchor. */}
       <ChatUserMinimap
         entries={minimapSourceEntries}
         activeIndex={activeFullUserOrdinal}
@@ -6707,8 +6729,9 @@ function AgentChatMessageListMain({
         onRetryOlderHistory={onRetryOlderHistory}
         listWidthPx={listRootBoxPx.width}
         listHeightPx={listRootBoxPx.height}
-        listTopViewportPx={listRootBoxPx.top}
         columnWidthPx={columnWidthPx}
+        keyboardFocusIndex={promptHistoryFocusIndex}
+        keyboardFocusRequestId={scrollToPromptHistoryRequest?.requestId ?? null}
       />
       <div
         ref={scrollRef}

apps/desktop/src/renderer/components/chat/AgentChatPane.test.tsx

@@ -1435,11 +1435,9 @@ describe("AgentChatPane remote startup", () => {
 });
 
 describe("AgentChatPane pane reserve", () => {
-  // Wide enough that a floating pane does NOT fit in the centered column's own
-  // side margin ((1000 - 832) / 2 = 84px < the 276px pane), so the chat must
-  // reserve a gutter — the only regime where this bug is visible at all.
+  // Wide enough that a right chat-actions pane does NOT fit in the centered
+  // column's own side margin ((1000 - 832) / 2 = 84px < the 276px pane).
   const OBSERVED_WIDTH_PX = 1000;
-  const EXPECTED_RESERVE = "276px";
   let originalResizeObserver: unknown;
 
   beforeEach(() => {
@@ -1473,7 +1471,7 @@ describe("AgentChatPane pane reserve", () => {
     return shell.style.getPropertyValue("--chat-pane-reserve-left").trim();
   }
 
-  it("reserves a left gutter for the floating PR pane on the session surface", async () => {
+  it("keeps the left reserve at zero for the floating PR pane", async () => {
     const session = buildSession("session-1", { title: "PR pane chat" });
     installAdeMocks({ sessions: [session] });
     seedDrawerStore();
@@ -1482,9 +1480,7 @@ describe("AgentChatPane pane reserve", () => {
 
     const { container } = renderPane(session);
 
-    await waitFor(() => {
-      expect(readLeftReserve(container)).toBe(EXPECTED_RESERVE);
-    });
+    await waitFor(() => expect(readLeftReserve(container)).toBe("0px"));
   });
 
   it("reserves nothing on the draft surface, which renders no floating panes", async () => {