A pipeline stage that arrives as an untyped value now follows Node's
stage ladder for more shapes. As the first stage, a function is a source
function: the pipeline calls it with { signal } while it is set up and
pumps its result, which must be iterable (ERR_INVALID_RETURN_VALUE
otherwise), and a { readable, writable } pair pumps its readable side.
After the first stage, the pipeline call is lowered once per combination
of its first three untyped stages being functions or not, and a typeof
test picks the branch at run time. A function stage is called with the
previous stage and { signal }; before the last stage its result must be
async iterable, and as the last stage a promise resolves the pipeline's
value and an async iterable feeds the PassThrough pipeline() returns
(SCR_PIPE_DEST_DYN). Any other value that is not a stream becomes
Duplex.from of it, which the next stage reads from without the previous
stage being piped into it, and Duplex.from's ERR_INVALID_ARG_TYPE for
the values it rejects.
An untyped stage followed by an untyped function stage hands its value to
that stage through a cell created per pipeline call, so the function
receives the previous stage's own iterator, as Node's makeAsyncIterable
answers it, instead of an async generator over it.
Untyped web streams, pairs after the first stage, and function stages
that return a stream throw the not-supported error.
RUNTIME_ABI_VERSION goes from 45 to 46 for the new stream exports.
Records inherit toString, toLocaleString, valueOf, hasOwnProperty,
isPrototypeOf and propertyIsEnumerable. Calls of these methods by name
run an own callable entry when the record's type allows one and the
record holds it, and otherwise the built-in with the record as receiver;
toLocaleString, valueOf and isPrototypeOf on records were refused, and
toString ignored an own entry. Keyed reads of records of functions answer
the built-in as a native function value when the key misses: bound to the
record when called at once, with an undefined `this` otherwise. The
backend fuses the read with its fallback, so hits cost nothing extra.
Records of other value types keep reading undefined for these names; the
limitations page says so.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Preflight admits a createRequire loader's require.resolve call with a
computed request inside a try block, but lowering refused the call, so
in JavaScript source the whole statement became a runtime fence. The
fence threw before the request expression ran, and before anything else
in the statement: `try { where = load.resolve(candidate(name)); }`
skipped candidate()'s side effects, so the catch clause saw a different
state than in Node.
Such calls (a computed request, another argument shape, or
runtime-computed options, on require.resolve and require.resolve.paths)
now evaluate their arguments in order and then throw the fence, as a
computed require call does. The addon-probe fixture checks that a
computed candidate path runs before each failed lookup.
A pipeline whose first stage is a checked-dynamic value now checks it at
run time, as Node's stage ladder does: a stream is piped as before, and a
string or a value with a Symbol.asyncIterator or Symbol.iterator method is
pumped into the next stage through an async generator over its iterator.
A typed Set, Map, generator or async generator object as the first stage
takes the same path. This covers the callback and stream/promises forms,
with or without function stages and pipeline options.
A write whose callback fails synchronously no longer sets needDrain, so no
'drain' follows the error and a pumped source stops at the failed write,
as in Node.
RUNTIME_ABI_VERSION goes from 37 to 42 for scr_stream_dyn_iterable_source.
tls.connect, https.request and http2.connect verified the server against
the default CAs when ca was an empty Buffer, because the runtime read a
zero-length ca as none. The compiled calls now pass a null ca for none
(an omitted ca, or an empty string, which Node reads as no ca) and a
non-null one for any Buffer, and runtime option records read ca the same
way, so an empty Buffer or array trusts no certificate, as in Node. The
connection pool keys tell an empty ca from none. An empty array, which
threw, is an empty trust store too. A runtime-valued empty string ca in
http2.connect is refused instead of being read as an empty store.
In JavaScript dependencies, a createRequire require call with a computed
specifier, and require.resolve called with a computed request or read as
a value, now compile. The new runtime unit scr_require.c resolves the
specifier with Node 24's CommonJS algorithm (builtins, relative and
absolute paths with Node's extension search, package "main", "exports"
and self-reference, node_modules and NODE_PATH lookup) when the call runs:
- require.resolve returns the id or real path Node returns, and throws
Node's MODULE_NOT_FOUND error when nothing resolves.
- require throws the same MODULE_NOT_FOUND error when nothing resolves,
so packages that probe for optional addons, such as pi-tui, take their
absent branch as in Node. When the specifier resolves to a native addon,
a builtin or another file, Node would load that module: the program
prints an SC2020 error naming it and exits with status 1, without
running the catch clause around the call.
Coverage lists these calls as deferred to runtime. TypeScript sources keep
the compile-time refusal.
Refs #1777.
The checker resolves an overloaded call whose argument is `any` to the
first overload that argument satisfies, but in JavaScript the value can
select another one: generateKeyPairSync("ec", options) returns KeyObjects
or PEM strings by the options, and digest(encoding) returns a Buffer when
the encoding is undefined. The result was converted to the first
overload's return type, so such calls threw a TypeError where Node
returns the other overload's value.
When a checked-dynamic argument could take another overload whose return
type differs (trailing untyped or undefined arguments may also be
absent), the call's result in a JavaScript source is checked-dynamic. So
are the unannotated bindings it initializes, destructured or not, and
the unannotated functions that return it. fs.globSync keeps choosing its
result form from the resolved overload, since the runtime checks that
withFileTypes agrees with it.
Object.freeze, Object.seal and Object.preventExtensions of a class
instance held in an untyped value threw SC2020 at run time. Node changes
the instance itself: writes through its typed references then throw the
read-only TypeError in strict mode code, adding properties through any
reference fails, and Object.isFrozen, isSealed and isExtensible report
the state through either reference.
- In a program that freezes, seals or prevents extensions of an untyped
value that is not a fresh literal, every class hierarchy that can be held
there gets the integrity word that static Object.freeze already uses, and
with it the existing write checks.
- The runtime applies the operation to the instance's checked view and
commits the view. The commit of such a hierarchy stores the view's
integrity state in the word (scr_dyn_class_view_integrity) and makes the
instance's property bag not extensible with it. A hierarchy without the
word still throws SC2020.
- These commits replace and remove the bag's field entries whatever their
attributes, so a sealed or frozen view does not leave stale field values
in the bag.
- The analysis behind records and arrays now starts from these calls only,
rather than from every untyped freeze the lowering emits, such as the
frozen strings array of a tagged template.
- Programs without such calls compile as before. The runtime ABI moves to
v38.
Corpus 7407 covers freeze, seal and preventExtensions through unknown of
classes and subclasses, writes through typed and untyped references and
through methods, properties added before and after the operation, and the
integrity queries, and matches Node.
Refs #1374
Co-authored-by: blurname <50226652+blurname@users.noreply.github.com>
Chris Tate