fix(cdp): let evaluateJson target a specific session
amankumarsingh77 amankumarsingh7702@gmail.com
Mon, 27 Jul 2026 23:02:59 +0530
2 files changed,
68 insertions(+),
11 deletions(-)
M
src/cdp/evaluate.ts
→
src/cdp/evaluate.ts
@@ -2,22 +2,21 @@ import { type Result, err, ok } from "../util/result";
import { type CdpError, cdpError } from "./errors"; import type { CdpSession } from "./session"; -/** - * Runtime.evaluate, unwrapped and narrowed. Runs `expression`, surfaces a page - * exception as an error, then applies `check` to the returned value — the - * sanctioned way to turn `unknown` evaluate output into a typed `T` without a - * cast. - */ export const evaluateJson = async <T>( session: CdpSession, expression: string, check: (v: unknown) => v is T, + opts?: { sessionId?: string | undefined; timeoutMs?: number | undefined }, ): Promise<Result<T, CdpError>> => { - const r = await session.call("Runtime.evaluate", { + const params = { expression, returnByValue: true, awaitPromise: true, - }); + }; + const callOpts = opts?.timeoutMs !== undefined ? { timeoutMs: opts.timeoutMs } : {}; + const r = opts?.sessionId !== undefined + ? await session.callOnTarget("Runtime.evaluate", params, opts.sessionId, callOpts) + : await session.call("Runtime.evaluate", params, callOpts); if (!r.success) return r; const { result, exceptionDetails } = r.data; if (exceptionDetails !== undefined) {@@ -25,7 +24,7 @@ return err(cdpError("remote_error", exceptionDetails.text, "Runtime.evaluate"));
} const value = result.value; if (!check(value)) { - return err(cdpError("invalid_response", `unexpected evaluate shape for: ${expression.slice(0, 60)}`, "Runtime.evaluate")); + return err(cdpError("invalid_response", `unexpected evaluate shape (type: ${result.type}) for: ${expression.slice(0, 60)}`, "Runtime.evaluate")); } return ok(value); };
M
test/cdp/evaluate-test.ts
→
test/cdp/evaluate-test.ts
@@ -2,7 +2,7 @@ import { test, describe } from "node:test";
import assert from "node:assert/strict"; import { evaluateJson } from "../../src/cdp/evaluate"; import type { CdpSession } from "../../src/cdp/session"; -import { ok } from "../../src/util/result"; +import { err, ok } from "../../src/util/result"; const isNumberArray = (v: unknown): v is ReadonlyArray<number> => Array.isArray(v) && v.every((x) => typeof x === "number");@@ -12,6 +12,23 @@ ({
call: async () => ok(payload), }) as unknown as CdpSession; +type Call = { method: string; args: unknown[] }; + +const recordingSession = (result: unknown): { session: CdpSession; calls: Call[] } => { + const calls: Call[] = []; + const session = { + call: async (...args: unknown[]) => { + calls.push({ method: "call", args }); + return result; + }, + callOnTarget: async (...args: unknown[]) => { + calls.push({ method: "callOnTarget", args }); + return result; + }, + } as unknown as CdpSession; + return { session, calls }; +}; + describe("evaluateJson", () => { test("unwraps result.value and applies the guard", async () => { const s = fakeSession({ result: { type: "object", value: [1, 2, 3] } });@@ -27,7 +44,10 @@ exceptionDetails: { text: "ReferenceError: x is not defined" },
}); const r = await evaluateJson(s, "x", isNumberArray); assert.equal(r.success, false); - if (!r.success) assert.match(r.error.message, /ReferenceError/); + if (!r.success) { + assert.equal(r.error.kind, "remote_error"); + assert.match(r.error.message, /ReferenceError/); + } }); test("rejects a value that fails the guard", async () => {@@ -35,5 +55,43 @@ const s = fakeSession({ result: { type: "string", value: "nope" } });
const r = await evaluateJson(s, "'nope'", isNumberArray); assert.equal(r.success, false); if (!r.success) assert.equal(r.error.kind, "invalid_response"); + }); + + test("dispatches via callOnTarget when opts.sessionId is set", async () => { + const { session, calls } = recordingSession(ok({ result: { type: "object", value: [4, 5] } })); + const r = await evaluateJson(session, "[4,5]", isNumberArray, { sessionId: "sess-1" }); + assert.equal(r.success, true); + if (r.success) assert.deepEqual(r.data, [4, 5]); + assert.equal(calls.length, 1); + assert.equal(calls[0]?.method, "callOnTarget"); + const [, , sessionIdArg] = calls[0]?.args ?? []; + assert.equal(sessionIdArg, "sess-1"); + }); + + test("dispatches via call when no opts are given", async () => { + const { session, calls } = recordingSession(ok({ result: { type: "object", value: [1] } })); + const r = await evaluateJson(session, "[1]", isNumberArray); + assert.equal(r.success, true); + assert.equal(calls.length, 1); + assert.equal(calls[0]?.method, "call"); + assert.equal(calls.some((c) => c.method === "callOnTarget"), false); + }); + + test("passes timeoutMs through to the transport options", async () => { + const { session, calls } = recordingSession(ok({ result: { type: "object", value: [1] } })); + await evaluateJson(session, "[1]", isNumberArray, { timeoutMs: 5000 }); + const [, , optsArg] = calls[0]?.args ?? []; + assert.deepEqual(optsArg, { timeoutMs: 5000 }); + }); + + test("passes through a transport failure unchanged", async () => { + const failure = err({ kind: "timeout" as const, message: "timed out" }); + const { session } = recordingSession(failure); + const r = await evaluateJson(session, "[1]", isNumberArray); + assert.equal(r.success, false); + if (!r.success) { + assert.equal(r.error.kind, "timeout"); + assert.equal(r.error.message, "timed out"); + } }); });