M src/cdp/session.ts → src/cdp/session.ts

@@ -369,12 +369,11 @@ if (existing) {
         // Each Target.attachToTarget produces a new sessionId — update it.
         sessionIdToTargetId.delete(existing.sessionId);
         existing.sessionId = attachedSessionId;
-        sessionIdToTargetId.set(attachedSessionId, tid);
       } else {
         tabs.set(tid, tab);
-        await enableDomains(attachedSessionId);
-        sessionIdToTargetId.set(attachedSessionId, tid);
       }
+      sessionIdToTargetId.set(attachedSessionId, tid);
+      await enableDomains(attachedSessionId);
       // Update global pointers to point at the new active tab
       sessionId = tab.sessionId;
       targetId = tid;

A test/cdp/session-switch-test.ts

@@ -0,0 +1,66 @@
+import { test, describe } from "node:test";
+import assert from "node:assert/strict";
+import { createCdpSession } from "../../src/cdp/session";
+import { createOwnershipRegistry } from "../../src/cdp/ownership";
+import { createStubTransport } from "../domains/fake-client";
+import { ok } from "../../src/util/result";
+
+const ENABLED_DOMAINS = ["Page", "DOM", "Runtime", "Network", "Accessibility", "Log"];
+
+const twoTabSession = async () => {
+  const stub = createStubTransport({
+    "Target.setDiscoverTargets": ok({}),
+    "Target.getTargets": ok({
+      targetInfos: [
+        { targetId: "t1", type: "page", title: "One", url: "https://one.test/" },
+        { targetId: "t2", type: "page", title: "Two", url: "https://two.test/" },
+      ],
+    }),
+    "Target.attachToTarget": [ok({ sessionId: "s1" }), ok({ sessionId: "s2" }), ok({ sessionId: "s3" })],
+    "Browser.getWindowForTarget": ok({ windowId: 7 }),
+    "Target.activateTarget": ok({}),
+  });
+  const ownership = createOwnershipRegistry({ ownedTargetIds: ["t1", "t2"] });
+  const session = createCdpSession(stub.transport, ownership);
+  const attached = await session.attachFirstPage();
+  assert.equal(attached.success, true);
+  return { stub, session };
+};
+
+const enablesFor = (stub: { calls: ReadonlyArray<{ method: string; sessionId: string | null | undefined }> }, sessionId: string): string[] =>
+  stub.calls.filter((c) => c.sessionId === sessionId && c.method.endsWith(".enable")).map((c) => c.method);
+
+describe("CdpSession.switchTo domain enablement", () => {
+  test("a first visit enables every domain on the new session", async () => {
+    const { stub, session } = await twoTabSession();
+    const switched = await session.switchTo("t2");
+    assert.equal(switched.success, true);
+    assert.deepEqual(
+      enablesFor(stub, "s2").sort(),
+      ENABLED_DOMAINS.map((d) => `${d}.enable`).sort(),
+    );
+  });
+
+  test("returning to a known tab re-enables domains on its new session", async () => {
+    const { stub, session } = await twoTabSession();
+    await session.switchTo("t2");
+    const back = await session.switchTo("t1");
+    assert.equal(back.success, true);
+    assert.equal(session.current()?.sessionId, "s3");
+    assert.deepEqual(
+      enablesFor(stub, "s3").sort(),
+      ENABLED_DOMAINS.map((d) => `${d}.enable`).sort(),
+    );
+  });
+
+  test("calls on the returned-to tab are routed to its refreshed session id", async () => {
+    const { stub, session } = await twoTabSession();
+    await session.switchTo("t2");
+    await session.switchTo("t1");
+    const r = await session.call("Page.bringToFront", {});
+    assert.equal(r.success, true);
+    const last = stub.calls.at(-1);
+    assert.equal(last?.method, "Page.bringToFront");
+    assert.equal(last?.sessionId, "s3");
+  });
+});