@browsercore/testing

Protocol verification — RFC compliance tests, browser golden packet captures, integration tests, and benchmarking. Compares generated packets against captures from real browsers.

Responsibility

Verify that the protocol stacks produce byte-identical output to real browsers (RFC compliance) and measure their performance (benchmarking). Depends on every other @browsercore/* package but is NOT required by them — purely a test/QA tool.

What it does

The full specification is in docs/TEST-SUITE.md — 17 test categories, layered from unit checks up through real-world interoperability:

| # | Category | Layer | | --- | --- | --- | | 1 | TCP Transport | unit / loopback | | 2 | TLS Serialization | serialization | | 3 | Browser Profile Comparison | golden | | 4 | TLS Fingerprint | serialization | | 5 | HTTP/1.1 | RFC compliance | | 6 | HTTP/2 | serialization | | 7 | Header Profiles | golden | | 8 | Cookie Behavior | unit | | 9 | Compression | unit | | 10 | Redirect Handling | unit | | 11 | Session Resumption | serialization | | 12 | Connection Reuse | unit | | 13 | Error Handling | unit | | 14 | Packet Capture Comparison | golden / reference | | 15 | Real World Compatibility | reference | | 16 | Regression Tests | unit | | 17 | Performance Benchmarks | benchmark |

In short:

• Golden packet testing — load .bin captures recorded from real browsers (Chrome 140 (tls, http2), Firefox 128 (tls)) and compare our generated TLS ClientHellos, HTTP/2 SETTINGS/HEADERS frames, etc. against them. Safari 18, Edge 140, and Firefox 135 captures are not yet collected.
• RFC compliance — run focused test suites for TLS 1.3 (RFC 8446), HTTP/2 (RFC 9113), HTTP/1.1 (RFC 9110). These are currently stubs that throw.
• Benchmarking — measure handshake latency and request throughput at p50/p95/p99. These are currently stubs that throw.

Public API

import {
    compareAgainstGolden,
    runTlsCompliance,
    benchmarkTlsHandshake,
    GoldenMismatchError,
} from "@browsercore/testing";

// Compare our ClientHello against a Chrome 140 capture:
const result = compareAgainstGolden(myClientHello, "chrome-140:client-hello:1" as never);
console.log(result.matches);

// Run the TLS RFC compliance suite (stub — throws until implemented):
// const tlsResult = runTlsCompliance();
// console.log(tlsResult.pass);

// Benchmark a TLS handshake over 100 iterations (stub — throws until implemented):
// const stats = benchmarkTlsHandshake(100);
// console.log("p99:", stats.p99, "ms");

Types

| Export | Kind | Purpose | | --- | --- | --- | | compareAgainstGolden() | function | Compare bytes against a golden capture | | loadGolden() | function | Load a golden capture by id | | runTlsCompliance() | function | TLS RFC 8446 compliance suite | | runHttp2Compliance() | function | HTTP/2 RFC 9113 compliance suite | | runHttp1Compliance() | function | HTTP/1.1 RFC 9110 compliance suite | | benchmarkTlsHandshake() | function | TLS handshake benchmark | | benchmarkHttp2Request() | function | HTTP/2 request benchmark | | GoldenCapture | interface | A recorded packet capture | | ComparisonResult | interface | Outcome of a golden comparison | | BenchStats | interface | p50/p95/p99 latency stats |

Dependency graph

@browsercore/testing
  └─ @browsercore/fetch  @browsercore/http2  @browsercore/http1  @browsercore/cookies
        └─ @browsercore/profiles  @browsercore/tls  @browsercore/crypto
              └─ @browsercore/transport
                    └─ node:net / node:crypto

@browsercore/testing sits at the very top — it depends on everything and nothing depends on it.