node-v24-compatibility-meta.json held two values derived from the public
compatibility artifact: a content hash for the data URL and its row count.
Every compatibility change rewrote the hash line, so concurrent changes
conflicted on it. next.config.mjs now computes both from the committed
artifact and passes them to the page through Next's build-time env, with
the same values. The generator no longer writes the file, and its local
check compares the public artifact itself.
Packages whose declarations name WebAssembly types (quickjs-wasi,
photon-node, and therefore pi) failed scriptc's type check with SC0001
"Cannot find namespace 'WebAssembly'", because scriptc's ES-only type
world never loads lib.dom, so `scriptc coverage` could not analyze them.
- scriptc.d.ts declares lib.dom's WebAssembly namespace and BufferSource
(admitting every ArrayBufferView, so Node's Buffer types fit).
- The type mapper gives every type declared in the namespace, and unions
over one, the checked-dynamic representation, so declarations that only
mention them compile.
- Every reached use of the API value refuses at its site with a named
SC2020 diagnostic: `WebAssembly.<member>` reads and calls,
`new WebAssembly.<Class>`, `instanceof WebAssembly.<Class>`, the bare
namespace, `globalThis.WebAssembly`, and the global object viewed
through a cast to a type with a WebAssembly member (pi codemode's
spelling). TypeScript sources fail the build; JavaScript sources get a
located runtime fence.
- `typeof WebAssembly` and `typeof WebAssembly.<member>` need no value and
fold to Node's answers ("object", "function"), including inside
`typeof x === "..."` tests, so feature probes in JavaScript glue behave
as in Node. Before, a JavaScript probe answered "string" (the identity
token) and silently took the non-wasm branch.
- The surface manifest projects the refusal (stdlib.webassembly), and the
compatibility ledger's `WebAssembly` global row moves from
not-implemented to refused; no other row changes.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
node:test changes, matching Node 24.22:
- A describe or suite body may take its SuiteContext, with name,
fullName, filePath, attempt, passed and diagnostic. Its passed is false
until the suite has finished, after its after hooks.
- before and after hooks may take the suite's context, and beforeEach
and afterEach hooks the test's. A test's t.before, t.after,
t.beforeEach and t.afterEach hooks may take the test's context.
- SuiteContext maps to the runner node that TestContext maps to, so the
TestContext members that SuiteContext shares lower the same way.
The suite-context fixture compares the reporter output and the order of
the bodies and hooks with Node, plain and with SCRIPTC_SAN=1.
node:test changes, matching Node 24.22:
- t.filePath is the entry file's path, as Node's entryFile, fixed when the
program is compiled.
- t.attempt is 0, since a test runs once.
- t.passed is false while the body runs and the test's outcome once the
body ends, so afterEach and t.after hooks see it, as Node's pass() and
fail() set it before them.
- t.workerId is Number(process.env.NODE_TEST_WORKER_ID) || undefined.
- t.tags is [], since the tags option has no lowering.
- A test's t.before, t.after, t.beforeEach and t.afterEach hooks are
released when the test ends. Hooks whose closures capture the test's
context no longer keep it alive in a cycle, which the SCRIPTC_SAN=1
audit reported as live closures at exit.
The ctx-members fixture compares the reporter output with Node, plain and
with SCRIPTC_SAN=1.
promisify(crypto.randomBytes), pbkdf2, scrypt, hkdf, randomFill, randomInt
and generateKey, and promisify(dns.lookup) and dns.lookupService, over a
named or namespace import, now lower. A call through the binding runs the
callback form with a runtime callback that settles the returned promise
where the callback would run: fulfilled with the callback's value, or
rejected with its error. An argument error the callback form throws rejects
the promise instead, as the throw inside Node's promisify wrapper does.
The crypto promise's value follows the declared result type: a Buffer,
the filled view (the same object), a number, or a checked-dynamic value
where @types/node declares unknown (scrypt, randomFill, randomInt) and for
ArrayBuffer and KeyObject results. The runtime adds a callback closure that
owns the promise and settle adapters for each representation, next to the
existing callback forms in scr_crypto_async.c.
dns.lookup's promise fulfills with { address, family }, or the address
array with options.all, and lookupService's with { hostname, service }, as
Node's custom promisified forms do. The runtime builds the checked-dynamic
result; a declared record type is reached through an async helper that
awaits it and checks the value. The type mapper maps the promisified
lookupService result literal like the promisified exec result.
The fallback declarations gain the matching util.promisify overloads.
exec(command, callback) and exec(command, { encoding, maxBuffer },
callback) lower like execFile's callback slice. The command line runs
with /bin/sh -c, as execSync runs it, the call returns the live
ChildProcess, and the error-first callback receives the captured utf8
stdout and stderr. A non-zero exit, including the shell's 127 for a
missing command, reports Node's "Command failed: <command>\n<stderr>":
scr_exec_file takes a shell flag so the message shows the command line.
Under @types/node, child_process.ExecException maps to Error, as
ExecFileException does. Its code member is the child's numeric exit
status, which the runtime error's string code slot does not hold, so
reading it, testing it with `in`, or testing its typeof is a named
refusal.
- node:punycode: encode, decode, toASCII, toUnicode, ucs2.decode,
ucs2.encode and version, ported from the punycode.js 2.1.0 Node bundles
(scr_url.c), with its RangeErrors. DEP0040 follows Node: a static ES
import reports before any module evaluates and before the program can
register a 'warning' listener; require() reports on the next tick, once
for both spellings, not when a dependency under node_modules loads the
module first, and not under process.noDeprecation.
- node:constants: the frozen object Node builds from os.constants'
dlopen, errno, priority and signals groups, fs.constants (node_constants.cc
order and guards) and crypto.constants (scr_os.c); its bindings read it as
a checked-dynamic value.
These unblock tr46 (whatwg-url, node-fetch@2) and graceful-fs (fs-extra).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Reads of defaultMaxListeners through an ES module namespace import or a
named import answer the namespace's copy of the export, which keeps its
value from program start until module.syncBuiltinESMExports() refreshes it,
as in Node. The default import, the EventEmitter class and CommonJS module
bindings keep reading the current default. A destructured CommonJS binding
of defaultMaxListeners, which held a placeholder string in JavaScript
files, is refused.
node:test changes, matching Node 24.22:
- t.assert.snapshot(value[, options]) serializes the value with Node's
default serializer, JSON.stringify(value, null, 2), or with an
options.serializers array literal applied in order, and compares it
with assert.strictEqual against the snapshot stored under
"<test full name> <n>" in "<entry file>.snapshot".
- t.assert.fileSnapshot(value, path[, options]) compares the serialized
value with the contents of path.
- Snapshot files are read in the form Node writes them, exports[`key`] =
`value`; statements, with template escapes and CRLF line endings
cooked as in a template literal.
- Missing snapshots, unreadable snapshot files and throwing serializers
throw Node's ERR_INVALID_STATE errors, with Node's messages.
- Running the binary with Node's --test-update-snapshots flag as its
first argument records the values and writes the snapshot files after
the last test, keys sorted as Node sorts them. The flag is kept out of
process.argv and appears in process.execArgv, which is otherwise [].
- Snapshot assertions count toward the test's plan.
The snapshot fixture compares the reporter output with Node, plain and
with SCRIPTC_SAN=1, against a snapshot file Node wrote. The update-mode
harness test runs Node and the binary with --test-update-snapshots and
compares the files they write. The node:test normalization also drops
the "... N lines matching cause stack trace ..." line Node prints for an
error cause, with the stack frames it summarizes.
markAsUncloneable(value) marks a plain object, a record, an error or a
class instance (scr_json.c); structuredClone and postMessage then throw
DataCloneError "Cannot clone object of unsupported type." for it, also
where it is nested. As in Node, the mark has no effect on primitives,
arrays, typed arrays and ArrayBuffers. Marked values are retained until
the thread exits; with nothing marked, the clone paths add one branch.
worker[Symbol.asyncDispose]() terminates the worker and resolves with
undefined after its 'exit' event, so `await using` disposes a Worker at
the end of its block. The Worker handle's symbol_get op answers the
well-known symbol: the symbol unit registers Symbol.asyncDispose with the
dyn core when the program names it, and scr_dyn_is_async_dispose_symbol
tells the worker unit, so worker programs that never name the symbol do
not link the symbol unit.
static-support.json adds rows for markAsUncloneable, isInternalThread
(already lowered as false and declared) and worker[Symbol.asyncDispose]().
Corpus 5990-5991 match Node v24.22.0; corpus-costs.json records their
costs.
A Hash or Hmac that flows into an unknown or any slot, or into untyped
JavaScript code, is now a native handle (Hash or Hmac) instead of a
compile error. The handle keeps the value's identity, so a cast back to
Hash or Hmac answers the same value. update(), digest() and Hash's
copy() dispatch through it, called directly or read as values: update
is one function for Hash and Hmac and digest is one per class, as in
Node 24.22, and update() answers the receiver. The stream and event
members throw a coded SC2020 error there, as do the methods called with
another receiver; other names read as undefined.
The to-dyn conversion boxes a Hash or Hmac through
scr_crypto_hash_to_dyn, which installs the handle ops on first use, so
programs that never box one link none of the handle code.
A native handle read through `as any` now dispatches its method calls
through the handle. Calling copy() on an Hmac throws Node's TypeError
("mac.copy is not a function") after the arguments are evaluated,
instead of the method-call fence.
Corpus 5768 and 5769 cover the TypeScript and JavaScript forms against
Node 24.22, and errors.test.ts covers the SC2020 cases. corpus-costs.json
records their plain and sanitized costs.
- util.format %d and %i format bigint, symbol, null and undefined arguments
- util.format %j prints [Circular] for circular arguments
- util.types answers the remaining brand checks
- util.inspect prints WeakMap, WeakSet, Date and numeric typed array values as Node does
- util.inspect lowers the breakLength, compact and sorted options
- URLSearchParams iterators compile outside a for-of head
- URLSearchParams can be built from [string, string] tuple pairs
- querystring.stringify writes bigint values
- StringDecoder accepts an encoding known only at run time
- os.setPriority is lowered
- The EventEmitter leak warning reaches process 'warning' listeners on the next tick
- The events listener-count and max-listener helpers work over EventEmitter instances
- timers/promises setTimeout, setImmediate and scheduler.wait accept an AbortSignal
- timers/promises scheduler.wait and scheduler.yield are lowered
net.SocketAddress and net.BlockList were refused at compile time. They
are now native checked-dynamic handles in scr_net.c, so their getters
and methods also work on untyped values, and they match Node 24:
- new SocketAddress(options) checks the options in Node's order
(ERR_INVALID_ARG_TYPE, ERR_INVALID_ARG_VALUE for the family,
ERR_SOCKET_BAD_PORT, ERR_OUT_OF_RANGE for the flow label) and throws
ERR_INVALID_ADDRESS for an address that does not parse. parse() reads
URL.parse(`http://${input}`)'s hostname and port and answers undefined
on failure; isSocketAddress(), toJSON() and util.inspect match.
- BlockList takes address, range, subnet and CIDR rules (addAddress,
addAddresses, addRange, addSubnet, addCIDR, addCIDRs), removes them
(removeAddress, removeRange, removeSubnet, removeCIDR, clear) and lists
them in Node's order: IPv4 addresses, IPv6 addresses, subnets, then
ranges, each newest first, with a repeated address kept once.
- check() compares across families through the IPv4-mapped IPv6 form,
as Node's SocketAddress::compare and is_in_network do, and answers
false for a string that does not parse in the given family.
- rules, size, toJSON(), fromJSON() (Node's rule patterns), isBlockList(),
PRIVATE_RANGES, instanceof and util.inspect match, with the validation
errors of lib/internal/blocklist.js.
Corpus 5659 and the node-types fixture net-blocklist.ts cover both
classes.
The compatibility registry lists the BlockList methods and
SocketAddress.parse as supported, and both classes as partial: their
structured clone and worker transfer forms are not modeled.
promisify(zlib.deflate) and the other callback one-shots (inflate,
deflateRaw, inflateRaw, gzip, gunzip, unzip) over a named or namespace
import of node:zlib now lower. A call through the binding,
gzipAsync(data, options?), runs the callback form's work on the worker
pool and returns a promise that settles where the callback would run:
fulfilled with the Buffer, or rejected with the callback form's Error
(errno, code and message). An invalid option or input rejects the promise
instead of throwing, as the throw inside Node's promisify wrapper does.
The runtime adds scr_zlib_codec_promise and its checked-dynamic twin,
which share the callback forms' options ladder and worker-pool operation
and settle a pending promise in place of the callback. The fallback
declarations gain the matching util.promisify overload.
Chris Tate