Improve Node.js compatibility for process, fs, http, events, and navigator

[danlapid]

Add missing properties and constants identified by the node_compat matrix to close gaps between workerd and Node.js. All changes are additive — they either populate previously missing properties with Node.js-compatible values or fix export wiring so existing values are reachable. I believe no compat flag should be needed because:

• New properties on existing objects (process.config.variables, stdio socket-like properties, EventEmitter.domain, globalAgent options fields) cannot break existing code since the keys didn't exist before, and all values match Node.js defaults.
• process.config previously had empty target_defaults/variables objects, so code reading specific config keys got undefined before and gets the correct value now. Code checking for emptiness is unlikely since the empty stub was useless.
• fs.promises.constants was missing due to an export wiring issue — the constants existed in the internal module but weren't re-exported through the promises entry point.
• The HTTP/HTTPS Agent constructor changes align with Node.js's actual initialization order (setting defaultPort/protocol/path/proxyEnv on this.options), which fixes missing keys on agent.options without changing any observable behavior for existing Agent usage.

Specific changes:

• process.config: Populate with representative Node.js build config stubs
• process.stdout/stderr/stdin: Add socket-like properties (bytesRead, connecting, readyState, writable*, readable*, etc.)
• fs.promises.constants: Re-export constants from internal_fs_promises
• http/https Agent: Match Node.js constructor flow for options.path, options.proxyEnv, options.defaultPort, options.protocol; add agentKeepAliveTimeoutBuffer and maxCachedSessions
• EventEmitter: Set domain = null in init() matching Node.js
• navigator.platform: Add read-only property returning "Linux"
• module.prototype.isPreloading: Add boolean stub
• events: Export captureRejections as named export

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UnknownError: ProviderInitError

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[github-actions]

The generated output of @cloudflare/workers-types matches the snapshot in types/generated-snapshot 🎉

[codspeed-hq]

Merging this PR will not alter performance

✅ 72 untouched benchmarks
⏩ 129 skipped benchmarks¹

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_{Comparing dlapid/moreNodeCompat (83053d0) with main (78dfd27)}

Footnotes

1. 129 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[danlapid]

/bonk review

[ask-bonk]

Review Summary

Overall this PR is a clean batch of additive Node.js compat stubs. A few items worth considering:

• [LOW] navigator.platform: Added unconditionally while language/languages are gated behind enableNavigatorLanguage. Confirm this is intentional — the spec says platform is deprecated but returning "" is the recommended deprecation path, not "Linux".
• [LOW] process.config.variables.node_shared_merve: Likely a typo — this field doesn't exist in Node.js's actual process.config.
• [LOW] export { constants } placement in internal_fs_promises.ts: Interleaved between import statements — technically valid but unusual; consider grouping with other exports.
• [LOW] process.config blob: ~100 lines of hardcoded values that may silently drift from Node.js over time.
• [INFO] The CodSpeed regression on simpleStringBody[Response] (-25%) is flagged as "different runtime environments" — likely CI noise unrelated to this PR.
• [INFO] The PR description mentions "events: Export captureRejections as named export" but this was already exported via export * in events.ts. No issue, just a documentation inaccuracy.

This review was generated by an AI assistant and may contain inaccuracies.

[ask-bonk]

Review posted successfully on PR #6575. Here's a summary of the findings:

7 inline comments across the changed files:

1. global-scope.h:118 — navigator.platform is added unconditionally while language/languages are behind a compat flag. The spec deprecates platform and recommends returning "". Adding "Linux" unconditionally is a new observable property on all workers, not just nodejs_compat.

2. internal_process.ts:284 — node_shared_merve is likely a typo. This key doesn't exist in Node.js's actual process.config.variables.

3. internal_process.ts:233 — The ~100-line process.config blob would benefit from a comment noting which Node.js version it was sourced from, and some values may be misleading in the workerd context (e.g., v8_enable_webassembly, v8_enable_inspector).

4. public_process.ts:107 — The addSocketProperties helper assigns readable-prefixed properties on SyncWriteStream (which extends Writable, not Duplex). Confirmed this shouldn't conflict since those properties don't exist on the Writable prototype, but asked for test confirmation.

5. internal_fs_promises.ts:67 — export { constants } is interleaved between import statements. Suggested keeping the re-export in the public promises.ts module for cleaner module boundary separation.

6. internal_https_agent.ts:23 — The ??= (nullish) vs || (falsy) inconsistency between HTTPS and HTTP agent defaultPort initialization. Also noted the shallow copy behavior.

7. events.ts:256 — domain = null on every EventEmitter instance matches Node.js but asked about test coverage.

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[petebacondarwin]

Approved for typings changes on behalf of Wrangler team