- EventEmitter.defaultMaxListeners on the untyped constructor is Node's
accessor over the default the typed EventEmitter reads: assignments
validate as validateNumber(arg, 'defaultMaxListeners', 0) does, and
getMaxListeners() of emitters without their own limit answers the new
value.
- dyn.builtinInstanceOf and dyn.functionInstanceOf link the
constructor-function unit and the units it calls (dyn-invoke, inspect,
symbol, emitter), so a program whose only use is `this instanceof F`
links.
- The legacy pipe's cleanup runs once: when the destination emits
'close' from end(), the cleanup still queued on the source's 'end'
finds the listeners removed and emit('end') answers true.
pipe() called from untyped JavaScript on a native stream went through
scr_stream_pipe directly, so a helper that piped into the converted
process.stdout or process.stderr ended it at the source's end, and later
writes through the program's NodeJS.WritableStream slots failed. The
stream view's pipe now calls scr_stream_pipe_general, which keeps end off
for those Writables, as Node's pipe() does for process.stdout and
process.stderr.
Adds corpus 6469.
Externrefs a guest holds are borrowed pointers. An import's result was
kept only until the outermost call returned, which was before the export
call converted its results to JavaScript, so a result created by an
import was freed before conversion. A table or global slot released the
reference it replaced at once, although the guest may still hold it in a
local after reading the slot. The kept references are now released after
the outermost caller has converted its results (scr_wasm_leave), and a
table or global store during a call keeps the reference it replaces until
then.
Checked memories (explicit bounds checks: sanitized builds, Windows)
grew with realloc, which can move the storage that memory.buffer and its
views alias. They now reserve the address space for their largest size
(mmap on POSIX hosts, VirtualAlloc on Windows) and commit pages as they
grow, so the base never moves. Hosts without address-space reservation
grow in place only until a buffer has been handed out; after that,
growth that would move the storage fails.
Tests: webassembly-externref-lifetimes.mjs (import results through an
export, table and global references replaced by the guest and by
JavaScript), webassembly-memory-growth.test.ts (views written after
growth from JavaScript and from the guest), and translate.test.ts cases
for memargs naming memory 0 explicitly and for local.tee operand types,
which b3bcbaaf7 made consistent with validation. Under SCRIPTC_SAN=1 the
two runtime tests report heap-use-after-free without these changes.
Merges main; internal/compatibility/generated/node-v24-backlog.json is
regenerated with pnpm node-compat.
- http.request, https.request and get validate each name and value of a
flat [name, value, ...] headers array, as Node's _storeHeader does: a
name that is not an HTTP token throws ERR_INVALID_HTTP_TOKEN, a value
with an invalid character throws ERR_INVALID_CHAR, and an odd length
throws ERR_INVALID_ARG_VALUE with the inspected array. The
[[name, value], ...] entry form throws the options fence.
- A closing socket drops its 'lookup' listeners with its other listeners,
so a listener that holds the socket no longer keeps it alive.
- The options-record diagnostics snapshot no longer expects the
socketPath refusal.
- A checked-dynamic entry of a tuple Promise.all goes through
PromiseResolve (`dyn.promiseResolve`): a native promise is itself, a
thenable adopts its settlement through its resolve job, and any other
value fulfills. Before, a thenable fulfilled the slot with the object.
- Tuple fields read their entry by position. Shape fields are sorted by
name, so tuples of more than ten entries paired fields with the wrong
entries.
Under the general stream representation, every conversion of
process.stdout or process.stderr into a Writable slot made a new stream,
so two NodeJS.WritableStream slots holding process.stdout compared
unequal and kept separate listeners and writable state. A pipe into such
a slot also ended the converted Writable at the source's end, so later
writes through the slot failed; Node never ends process.stdout or
process.stderr from a pipe.
scr_stream_stdio_writable now keeps one Writable per descriptor and
thread, released at exit. Under the general representation, a pipe into
a Writable slot lowers to readable.pipeGeneral (scr_stream_pipe_general,
last in the stream unit), which keeps end off when the destination is
one of those Writables; programs without the general representation
lower pipes as before.
The fallback stream.Writable's on() and once() overloads for drain,
finish, close and error return the stream again, so listener chains such
as out.on("finish", listener).end(data) type-check.
Adds corpus 6468.
Node answers a Unix-socket server's address() with its path. Programs
that call listen() with a string argument now get a Unix-aware
address(): typed `string | AddressInfo | null` (the @types/node
declaration), it answers the path; typed as the AddressInfo record alone,
which cannot hold the path, it throws for such a server, as does the
composed address().port read. Every other program keeps the record-only
lowering, so their output is unchanged.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
An 'unknown' value flowing or cast into a NodeJS.ReadableStream slot and
'for await' over one now select the general representation, where the
checked cast to Readable applies. pipeline() stages that arrive untyped
unwrap boxed native streams at run time. @types/node's zlib interface
declarations map to the runtime Transform.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
http.request, https.request and get now accept options the compiler
cannot see as an object literal: a RequestOptions variable, a literal
that spreads one, or a literal that sets socketPath. The runtime reads
the record in the ClientRequest constructor's order with Node's errors;
documented options it does not implement throw the runtime fence when
they carry a value. https adds rejectUnauthorized, ca and servername.
socketPath dials a Unix domain socket in the net unit; the agent keys
its sockets by the path as Node's getName does, and the Host header
defaults to localhost. server.listen(path[, cb]) binds a Unix socket and
removes the socket file when the server closes; a numeric string is
still a port. Errors name the path ("connect ENOENT /path", "listen
EADDRINUSE: address already in use /path"). Windows reports ENOTSUP.
A TypeScript object literal with no contextual type that spreads a
checked-dynamic value maps to the checked dynamic, so
`const options = { ...location, path, timeout }` compiles.
A socket's 'lookup' event reaches its listeners with (err, address,
family, host) for each address a host name resolves to, or once with
the lookup error, before 'connect'. Only programs that listen for
'lookup' install the lookup records; elsewhere the hook sites are a NULL
check.
server.close((err) => ...) runs the callback with undefined at 'close',
or with ERR_SERVER_NOT_RUNNING when the server was not listening; a
server that never listened now emits 'close'. IncomingMessage 'data'
listeners may take string chunks after setEncoding, and res.end()
accepts a string-or-undefined chunk.
fetch's BodyInit and HeadersInit unions, as RequestInit-derived option
types spell them under @types/node, map to the checked dynamic, and a
URLSearchParams body is sent form-encoded, as by Node.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
The fallback NodeJS stream interfaces declare Node's EventEmitter listener
signature for events beyond data/end, so checked JavaScript keeps its
contextual typing for process stream listeners. The child stdin fence
fixture becomes a differential test of the forms that now compile.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
An object literal with get/set accessors converted to `any` or `unknown`
listed its reserved closure slots (`%get:x`) as data keys, so a dynamic
read of the accessor answered undefined without calling the getter, and
Object.keys and JSON.stringify listed the slot instead of the property.
The checked-dynamic copy now defines each accessor as one enumerable,
configurable property whose getter and setter are the slot closures, in
declaration order: the record shape records its accessor key order
(`accessorOrder`). Live views of such records build that copy, and
checking a copy back into the record reads the closures from the
accessor's getter and setter. Reads, writes, Object.keys,
Object.entries, JSON.stringify and property descriptors answer as in
Node.
A value thrown from `unknown` storage (`throw values[i]`) that holds a
number, string or boolean now throws as that primitive, like a statically
typed `throw 5`. Before, it threw as a checked-dynamic reference, so
`typeof e === "number"` (and "string"/"boolean") on the catch
binding answered false and the narrowed reads were unreachable. A
primitive has no identity to keep, and reading the binding as `unknown`
converts it back.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Bundled npm code (glob, yazl, from2, multistream) subclasses Node's
classes with constructor functions: util.inherits(Ctor, EventEmitter) and
EventEmitter.call(this). util.inherits received an identity token and
threw ERR_INVALID_ARG_TYPE, EventEmitter.call(this) and
EventEmitter.prototype were refused, and `this instanceof Ctor` against
a function was refused.
A new runtime unit (scr_dyn_builtin_class.c, linked by the new
dynBuiltinClass feature) provides EventEmitter, the legacy Stream and
the stream classes as untyped constructor functions with Node's
prototype chain. EventEmitter's prototype ports lib/events.js over the
object's own _events, _eventsCount and _maxListeners properties; Stream
adds the legacy pipe. util.inherits, Base.call/apply(this, ...),
Base.prototype, instanceof on untyped values and JavaScript value reads
of these classes use them. Constructing over a stream class throws
SC2020 where it runs. instanceof against a compiled constructor function
compares its prototype with the value's prototype chain.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
A read through a computed key now counts as a stack read when the program
contains the string "stack", so `e[key]` captures frames like `e.stack`
does. A key the program assembles from other strings or from data it
reads keeps the static answer.
structuredClone of an error held as `any` copies a stack that was already
formatted as a non-enumerable data property, as it did before the stack
became an accessor.
When a name or message getter throws while the stack is formatted, the
stack accessor propagates the exception instead of reading the missing
string.
The trim helper returned parked workers' memory once no worker had run for
100 ms. A compiler in watch mode starts its workers again for each rebuild
and faulted the returned pages back in, and a rebuild that runs on the main
thread alone had the discards run alongside it.
- The delay starts at 1 s (SCR_SA_DISCARD_DELAY_MS) and doubles each time
workers start within ten delays of a discard, up to
SCR_SA_DISCARD_DELAY_MAX_MS (10 s by default).
- Once the event loop of the thread that is not a worker runs, the helper
discards one arena at a time, and only while that loop has been in one
wait with nothing ready for a step (scr_sa_loop_waiting, called by the
event loop around its sleep). A loop that does not wait gets the
discards SCR_SA_DISCARD_DELAY_MAX_MS after the delay.
- Programs without a running event loop discard after the delay, as before.
`s.charAt(i) === "c"`, and `s[i] === "c"` where the index is proven in
bounds, built a one-character string to compare with the literal. When
the literal is one UTF-16 code unit, the comparison now reads
`s.charCodeAt(i)` and compares the number. charCodeAt converts the index
the same way charAt does, and an index out of range answers NaN, which
equals no unit, as "" equals no one-unit literal. A switch on
`s.charAt(i)` whose case tests are all one-unit literals switches on the
code unit the same way.
A switch on a `string | undefined` value with string literal cases, such
as an array element or an optional field, lowered to a chain of union
equalities. It now tests for undefined, which matches no case, and
dispatches the string through the string switch: by byte length, then by
the literal's leading bytes.
`String.fromCharCode(a, b, ...)` with up to sixteen arguments passes the
codes to the runtime in a stack array instead of a heap f64[], and up to
64 code units encode into a stack buffer instead of a heap scratch block.
`.length` of a string that is not ASCII counts its UTF-16 units. The
string index keeps four entries, so a program that read the lengths of
more long texts than that in turn (the text of every source file) walked
each whole string on every read. Lengths of non-ASCII strings longer than
64 bytes now go into a 1024-slot table keyed by address, allocated by
the first length it records. A slot is dropped when the string is freed
or reallocated and when an append changes it in place, which is where
the index drops its facts.
Reading Object, Date, RegExp, Map, Set, Promise, WeakMap and WeakSet as
interned function values made every use of those globals a dynamic value,
including the receivers of member reads. The interned function models only
name, length and constructor, so `Map.prototype`, `Date.prototype.getYear`,
`Object.isFrozen` as a value, `Map["prototype"]` and `"prototype" in Map`
stopped reaching their SC2020/SC1090 fences and read undefined through the
dynamic paths instead (769 Test262 variants went from a refusal to a wrong
result).
A builtin global read for its members now keeps its member lowerings and
fences; only name, length and constructor read through the value. A member
read through an alias typed as the constructor's static side (`const D =
Date; D.prototype`) reports SC2020 before the generic field read. Passing
the value to Object or Reflect statics that reflect on or redefine its
members (`Object.hasOwn(Object, ...)`, `Object.defineProperty(Promise,
...)`, `hasOwnProperty.call(Map, ...)`) is refused; identity and the empty
enumerable key lists still compile. The interned functions answer Node's
lengths (Date 7, RegExp 2, Promise 1).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Node lists an object's own properties in creation order. An Error's own
`name` is created by an assignment after construction defines `message`
and `cause`, or during construction by a `name` field or a constructor's
`this.name = ...`. Errors listed an own `name` before `message`, and
instances of Error subclasses listed it before every field, so
Object.keys, Object.getOwnPropertyNames and JSON.stringify answered a
different order than Node's: `{"name":"E","extra":1}` for `{"extra":1,
"name":"E"}`.
An error's own-property view now lists `name` after the properties its
construction defines. For an Error subclass, the class records which
field `name` follows: a `name` field takes its place among the fields,
parameter properties first, and `this.name = ...` in a constructor follows
the fields created before it, including the ones that constructor assigns
in JavaScript sources. When no class of the chain sets `name` during
construction, an own `name` follows every other own property.
Object.getOwnPropertyNames, Reflect.ownKeys and
Object.getOwnPropertyDescriptors on errors held as `any` or `unknown`
listed "%error", the key that marks the checked-dynamic error encoding.
Node lists only the error's properties. The marker is now left out of
own property names; the runtime's own checks still read it.
Chris Tate