fix(web): Pull request panel entry works for linked PRs

apps/web/src/components/ChatView.tsx

@@ -264,7 +264,10 @@ import {
   selectThreadPreviewMiniPlayer,
   usePreviewMiniPlayerStore,
 } from "../previewMiniPlayerStore";
-import { pullRequestPanelContext } from "./pullRequest/pullRequestDetail.logic";
+import {
+  pullRequestPanelContext,
+  threadPullRequestPanelTarget,
+} from "./pullRequest/pullRequestDetail.logic";
 import { PullRequestDetailPanel } from "./pullRequest/PullRequestDetailPanel";
 import { PullRequestDetailGhost } from "./pullRequest/PullRequestGhosts";
 import { PullRequestsUnavailableState } from "./pullRequest/PullRequestsUnavailableState";
@@ -6613,12 +6616,20 @@ export default function ChatView(props: ChatViewProps) {
       },
     );
   }, [activeThreadReferenceCopyTarget]);
+  const pullRequestPanelTarget = activeThread
+    ? threadPullRequestPanelTarget({
+        projectId: activeThread.projectId,
+        pullRequests: visiblePullRequests,
+        linkedPullRequest: linkedThreadPullRequest,
+        branchPullRequest: activeThreadShell?.branchPullRequest ?? activeThread.branchPullRequest,
+      })
+    : null;
   const addPullRequestSurface = useCallback(() => {
-    if (!supportsPullRequests || activeThreadRef === null || linkedThreadPullRequest === null)
+    if (!supportsPullRequests || activeThreadRef === null || pullRequestPanelTarget === null)
       return;
-    useRightPanelStore.getState().openPullRequest(activeThreadRef, linkedThreadPullRequest);
-  }, [activeThreadRef, linkedThreadPullRequest, supportsPullRequests]);
-  const pullRequestSurfaceAvailable = supportsPullRequests && linkedThreadPullRequest !== null;
+    useRightPanelStore.getState().openPullRequest(activeThreadRef, pullRequestPanelTarget);
+  }, [activeThreadRef, pullRequestPanelTarget, supportsPullRequests]);
+  const pullRequestSurfaceAvailable = supportsPullRequests && pullRequestPanelTarget !== null;
   const supportsSettlement = serverConfig?.environment.capabilities.threadSettlement === true;
   const supportsSnooze = serverConfig?.environment.capabilities.threadSnooze === true;
   const supportsPinning = serverConfig?.environment.capabilities.threadPinning === true;

apps/web/src/components/pullRequest/pullRequestDetail.logic.test.ts

@@ -35,6 +35,7 @@ import {
   isStackedPullRequestBase,
   loadingPullRequestCheckoutCommand,
   pullRequestPanelContext,
+  threadPullRequestPanelTarget,
   latestPullRequestReviewOutcomes,
   newestPullRequestCommitAt,
   mergePullRequestThreadComments,
@@ -1535,6 +1536,54 @@ describe("pull request panel context beside a thread", () => {
     );
     expect(pullRequestPanelContext({ projectId: null }, surface(3))).toBe("page");
   });
+
+  describe("the Pull request entry's target", () => {
+    const legacy = (number: number) => ({
+      projectId: ProjectId.make("proj-a"),
+      repository: "pingdotgg/t3code",
+      number,
+      url: `https://github.com/pingdotgg/t3code/pull/${number}`,
+    });
+
+    it("opens a linked pull request the legacy field never named", () => {
+      // An agent's link_pull_request writes only the link list; the legacy field stays null.
+      const thread = {
+        projectId: "proj-a",
+        pullRequests: [link(15046, { source: "agent" })],
+        linkedPullRequest: null,
+      };
+      expect(threadPullRequestPanelTarget(thread)).toEqual({
+        projectId: "proj-a",
+        host: "github.com",
+        repository: "pingdotgg/t3code",
+        number: 15046,
+        url: "https://github.com/pingdotgg/t3code/pull/15046",
+      });
+    });
+
+    it("prefers the link list over a branch pull request", () => {
+      const thread = {
+        projectId: "proj-a",
+        pullRequests: [link(20, { source: "manual" })],
+        branchPullRequest: legacy(30),
+      };
+      expect(threadPullRequestPanelTarget(thread)?.number).toBe(20);
+    });
+
+    it("falls back to the legacy fields when the thread holds no visible link", () => {
+      expect(
+        threadPullRequestPanelTarget({ projectId: "proj-a", branchPullRequest: legacy(3) }),
+      ).toEqual(legacy(3));
+      expect(
+        threadPullRequestPanelTarget({
+          projectId: "proj-a",
+          pullRequests: [link(4, { source: "stack-dismissed" })],
+          linkedPullRequest: legacy(5),
+        }),
+      ).toEqual(legacy(5));
+      expect(threadPullRequestPanelTarget({ projectId: "proj-a", pullRequests: [] })).toBeNull();
+    });
+  });
 });
 
 describe("which actions need the host read again after they run", () => {

apps/web/src/components/pullRequest/pullRequestDetail.logic.ts

@@ -26,6 +26,7 @@ import {
   type VcsRef,
 } from "@t3tools/contracts";
 import {
+  resolveThreadCurrentPullRequestLink,
   threadPullRequestKeysEqual,
   visibleThreadPullRequests,
 } from "@t3tools/shared/threadPullRequests";
@@ -236,6 +237,31 @@ export function pullRequestPanelContext(
     : "page";
 }
 
+/**
+ * The pull request the right panel's "Pull request" entry opens for a thread, or null when the
+ * thread has none. Like `pullRequestPanelContext`, the link list decides when there is one, so a
+ * PR linked by an agent or the user enables the entry without the legacy field. The legacy
+ * fields answer only for servers that predate link lists, or a thread with only a branch PR.
+ */
+export function threadPullRequestPanelTarget(thread: {
+  readonly projectId: string;
+  readonly pullRequests?: ReadonlyArray<ThreadPullRequestLink> | undefined;
+  readonly linkedPullRequest?: ThreadLinkedPullRequest | null | undefined;
+  readonly branchPullRequest?: ThreadLinkedPullRequest | null | undefined;
+}) {
+  const current = resolveThreadCurrentPullRequestLink(thread.pullRequests ?? []);
+  if (current !== null) {
+    return {
+      projectId: thread.projectId,
+      host: current.host,
+      repository: current.repository,
+      number: current.number,
+      url: current.url,
+    };
+  }
+  return thread.linkedPullRequest ?? thread.branchPullRequest ?? null;
+}
+
 /** Names where a pull-request task will land, without letting each surface guess independently. */
 export function pullRequestHandoffLabels(inThisThread: boolean) {
   return inThisThread