Node.js - v21.1.0

Notable Changes

Automatically detect and run ESM syntax

The new flag --experimental-detect-module can be used to automatically run
ES modules when their syntax can be detected. For “ambiguous” files, which are
.js or extensionless files with no package.json with a type field, Node.js
will parse the file to detect ES module syntax; if found, it will run the file
as an ES module, otherwise it will run the file as a CommonJS module.
The same applies to string input via --eval or STDIN.

We hope to make detection enabled by default in a future version of Node.js.
Detection increases startup time, so we encourage everyone — especially package
authors — to add a type field to package.json, even for the default
"type": "commonjs". The presence of a type field, or explicit extensions
such as .mjs or .cjs, will opt out of detection.

Contributed by Geoffrey Booth in #50096.

Other Notable Changes

• [3729e33358] - doc: add H4ad to collaborators (Vinícius Lourenço) #50217
• [18862e4d5d] - (SEMVER-MINOR) fs: add flush option to appendFile() functions (Colin Ihrig) #50095
• [5a52c518ef] - (SEMVER-MINOR) lib: add navigator.userAgent (Yagiz Nizipli) #50200
• [789372a072] - (SEMVER-MINOR) stream: allow pass stream class to stream.compose (Alex Yang) #50187
• [f3a9ea0bc4] - stream: improve performance of readable stream reads (Raz Luvaton) #50173
• [dda33c2bf1] - vm: reject in importModuleDynamically without --experimental-vm-modules (Joyee Cheung) #50137
• [3999362c59] - vm: use internal versions of compileFunction and Script (Joyee Cheung) #50137
• [a54179f0e0] - vm: unify host-defined option generation in vm.compileFunction (Joyee Cheung) #50137

Commits

• [9cd68b9083] - buffer: remove unnecessary assignment in fromString (Tobias Nießen) #50199
• [a362c276ec] - crypto: ensure valid point on elliptic curve in SubtleCrypto.importKey (Filip Skokan) #50234
• [f4da308f8d] - deps: V8: cherry-pick f7d000a7ae7b (Luke Albao) #50302
• [269e268c38] - deps: update ada to 2.7.2 (Node.js GitHub Bot) #50338
• [03a31ce41e] - deps: update corepack to 0.22.0 (Node.js GitHub Bot) #50325
• [000531781b] - deps: update undici to 5.26.4 (Node.js GitHub Bot) #50274
• [f050668c14] - deps: update c-ares to 1.20.1 (Node.js GitHub Bot) #50082
• [ba258b682b] - deps: update c-ares to 1.20.0 (Node.js GitHub Bot) #50082
• [571f7ef1fa] - deps: patch V8 to 11.8.172.15 (Michaël Zasso) #50114
• [943047e800] - deps: V8: cherry-pick 25902244ad1a (Joyee Cheung) #50156
• [db2a1cf1cb] - doc: fix navigator.hardwareConcurrency example (Tobias Nießen) #50278
• [6e537aeb44] - doc: explain how to disable navigator (Geoffrey Booth) #50310
• [c40de82d62] - doc: add loong64 info into platform list (Shi Pujin) #50086
• [1c21a1880b] - doc: update release process LTS step (Richard Lau) #50299
• [2473aa3672] - doc: fix release process table of contents (Richard Lau) #50216
• [ce9d84eae3] - doc: update api stream.compose (Alex Yang) #50206
• [dacee4d9b5] - doc: add ReflectConstruct to known perf issues (Vinicius Lourenço) #50111
• [82363be2ac] - doc: fix typo in dgram docs (Peter Johnson) #50211
• [8c1a46c751] - doc: fix H4ad collaborator sort (Vinicius Lourenço) #50218
• [3729e33358] - doc: add H4ad to collaborators (Vinícius Lourenço) #50217
• [bac872cbd0] - doc: update release-stewards with last sec-release (Rafael Gonzaga) #50179
• [06b7724f14] - doc: add command to keep major branch sync (Rafael Gonzaga) #50102
• [47633ab086] - doc: add loong64 to list of architectures (Shi Pujin) #50172
• [1f40ca1b91] - doc: update security release process (Michael Dawson) #50166
• [998feda118] - esm: do not give wrong hints when detecting file format (Antoine du Hamel) #50314
• [e375063e01] - (SEMVER-MINOR) esm: detect ESM syntax in ambiguous JavaScript (Geoffrey Booth) #50096
• [c76eb27971] - esm: improve check for ESM syntax (Geoffrey Booth) #50127
• [7740bf820c] - esm: rename error code related to import attributes (Antoine du Hamel) #50181
• [0cc176ef25] - fs: improve error performance for readSync (Jungku Lee) #50033
• [5942edb774] - fs: improve error performance for fsyncSync (Jungku Lee) #49880
• [6ec5abadc0] - fs: improve error performance for mkdirSync (CanadaHonk) #49847
• [c5ff000cb1] - fs: improve error performance of realpathSync (Yagiz Nizipli) #49962
• [6eeaa02f5c] - fs: improve error performance of lchownSync (Yagiz Nizipli) #49962
• [dc9ac8d41c] - fs: improve error performance of symlinkSync (Yagiz Nizipli) #49962
• [bc6f279261] - fs: improve error performance of readlinkSync (Yagiz Nizipli) #49962
• [275987841e] - fs: improve error performance of mkdtempSync (Yagiz Nizipli) #49962
• [81f15274e2] - fs: improve error performance of linkSync (Yagiz Nizipli) #49962
• [f766c04856] - fs: improve error performance of chownSync (Yagiz Nizipli) #49962
• [610036c67d] - fs: improve error performance of renameSync (Yagiz Nizipli) #49962
• [18862e4d5d] - (SEMVER-MINOR) fs: add flush option to appendFile() functions (Colin Ihrig) #50095
• [3f8cbb15cb] - http2: allow streams to complete gracefully after goaway (Michael Lumish) #50202
• [1464eba1a0] - lib: improve performance of validateStringArray and validateBooleanArray (Aras Abbasi) #49756
• [5a52c518ef] - (SEMVER-MINOR) lib: add navigator.userAgent (Yagiz Nizipli) #50200
• [b6021ab8f6] - lib: reduce overhead of blob clone (Vinicius Lourenço) #50110
• [be19d9baa1] - meta: move Trott to TSC regular member (Rich Trott) #50297
• [91e373f8e9] - node-api: return napi_exception_pending on proxy handlers (Chengzhong Wu) #48607
• [531a3ae4b5] - stream: simplify prefinish (Robert Nagy) #50204
• [514ac86579] - stream: reduce scope of readable bitmap details (Robert Nagy) #49963
• [789372a072] - (SEMVER-MINOR) stream: allow pass stream class to stream.compose (Alex Yang) #50187
• [f3a9ea0bc4] - stream: call helper function from push and unshift (Raz Luvaton) #50173
• [a9ca7b32e7] - test: improve watch mode test (Moshe Atlow) #50319
• [63b7059efd] - test: set test-watch-mode-inspect as flaky (Yagiz Nizipli) #50259
• [7f87084b05] - Revert "test: set test-esm-loader-resolve-type as flaky" (Antoine du Hamel) #50315
• [4d390e2de4] - test: replace forEach with for..of in test-http-perf_hooks.js (Niya Shiyas) #49818
• [67c599ec39] - test: replace forEach with for..of in test-net-isipv4.js (Niya Shiyas) #49822
• [19d3ce2494] - test: deflake test-esm-loader-resolve-type (Antoine du Hamel) #50273
• [2d8d6c5701] - test: replace forEach with for..of in test-http2-server (Niya Shiyas) #49819
• [af31d51e5a] - test: replace forEach with for..of in test-http2-client-destroy.js (Niya Shiyas) #49820
• [465ad2a5ce] - test: update url web platform tests (Yagiz Nizipli) #50264
• [3b80a6894c] - test: set test-emit-after-on-destroyed as flaky (Yagiz Nizipli) #50246
• [57adbdd156] - test: set inspector async stack test as flaky (Yagiz Nizipli) #50244
• [6507f66404] - test: set test-worker-nearheaplimit-deadlock flaky (StefanStojanovic) #50277
• [21a6ba548d] - test: set test-cli-node-options as flaky (Yagiz Nizipli) #50296
• [c55f8f30cb] - test: reduce the number of requests and parsers (Luigi Pinca) #50240
• [5129bedfa2] - test: set crypto-timing test as flaky (Yagiz Nizipli) #50232
• [9bc5ab5e07] - test: set test-structuredclone-* as flaky (Yagiz Nizipli) #50261
• [317e447ddc] - test: deflake test-loaders-workers-spawned (Antoine du Hamel) #50251
• [0c710daae2] - test: improve code coverage of diagnostics_channel (Jithil P Ponnan) #50053
• [7c6e4d7ec3] - test: set test-esm-loader-resolve-type as flaky (Yagiz Nizipli) #50226
• [c8744909b0] - test: set inspector async hook test as flaky (Yagiz Nizipli) #50252
• [3e38001739] - test: skip test-benchmark-os.js on IBM i (Abdirahim Musse) #50208
• [dd66fdfb7b] - test: set parallel http server test as flaky (Yagiz Nizipli) #50227
• [a38d1311bf] - test: set test-worker-nearheaplimit-deadlock flaky (Stefan Stojanovic) #50238
• [8efb75fd80] - test: set test-runner-watch-mode as flaky (Yagiz Nizipli) #50221
• [143ddded74] - test: set sea snapshot tests as flaky (Yagiz Nizipli) #50223
• [ae905a8f35] - test: fix defect path traversal tests (Tobias Nießen) #50124
• [ce27ee701b] - tls: reduce TLS 'close' event listener warnings (Tim Perry) #50136
• [ab4bae8e1f] - tools: drop support for osx notarization with gon (Ulises Gascón) #50291
• [5df3d5abcc] - tools: update comment in update-uncidi.sh and acorn_version.h (Jungku Lee) #50175
• [bf7b94f0b3] - tools: refactor checkimports.py (Mohammed Keyvanzadeh) #50011
• [5dc454a837] - util: remove internal mime fns from benchmarks (Aras Abbasi) #50201
• [8f7eb15603] - vm: use import attributes instead of import assertions (Antoine du Hamel) #50141
• [dda33c2bf1] - vm: reject in importModuleDynamically without --experimental-vm-modules (Joyee Cheung) #50137
• [3999362c59] - vm: use internal versions of compileFunction and Script (Joyee Cheung) #50137
• [a54179f0e0] - vm: unify host-defined option generation in vm.compileFunction (Joyee Cheung) #50137
• [87be790fa9] - worker: handle detached MessagePort from a different context (Juan José) #49150