feat: add {stream,future}.forward canon builtins - #2614
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stream.forward canon builtinstream.splice canon builtin
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stream.splice canon builtinstream.{splice,forward} canon builtins
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stream.{splice,forward} canon builtins{stream,future}.forward canon builtins
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Pick up `wasmparser`/`wast`/`wasm-encoder` support for the `stream.forward` and `future.forward` canonical built-ins from bytecodealliance/wasm-tools#2614 until that lands upstream.
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Implement parsing, validation, encoding, and printing support for the
⏩-gated `stream.forward` built-in:
(canon stream.forward $streamT (core func $f))
where `$f` has type `(func (param i32 i32))`, taking a readable stream
end and a writable stream end. `stream.forward` transfers both ends
out of the calling instance and returns immediately with no result, so
it takes neither an `n` parameter nor an `async` immediate. It also
takes no `canonopt`s, since no elements pass through the caller's
linear memory.
The binary encoding uses opcode 0x2e as assigned in the proposed
specification change, and validation gates the built-in behind the
component model async and "more async builtins" features.
Assisted-by: claude:claude-fable-5
Signed-off-by: Roman Volosatovs <rvolosatovs@riseup.net>
Implement parsing, validation, encoding, and printing support for the
⏩-gated `future.forward` built-in:
(canon future.forward $futureT (core func $f))
where `$f` has type `(func (param i32 i32))`, taking a readable future
end and a writable future end. Exactly like its `stream.forward`
counterpart, `future.forward` transfers both ends out of the calling
instance and returns immediately with no result, so it takes neither
an `async` immediate nor any `canonopt`s, since the value does not
pass through the caller's linear memory.
The binary encoding uses opcode 0x2f as assigned in the proposed
specification change, and validation gates the built-in behind the
component model async and "more async builtins" features.
Assisted-by: claude:claude-fable-5
Recognize the `[stream-forward-N]` and `[future-forward-N]` mangled core import names in `wit-component` and wire them up to the corresponding `canon stream.forward` and `canon future.forward` built-ins when componentizing, following the same `prefixed_payload` pattern as the `drop-readable`/`drop-writable` intrinsics: `forward` takes no `canonopt`s and no `async` immediate, so no shim or memory plumbing is required and the built-in can be materialized directly. Also add `Forward` variants to `wit-parser`'s `StreamIntrinsic` and `FutureIntrinsic` name-mangling helpers so that bindings generators can emit the new intrinsic imports via `Resolve::wasm_import_name`. Assisted-by: claude:claude-fable-5
The `{stream,future}.forward` built-ins have now been merged into the
component model specification (WebAssembly/component-model#717) as
their own ➡️-gated feature rather than as part of the "more async
builtins" feature. Add a matching `cm_forward` flag to `WasmFeatures`,
gate validation of both built-ins on it, and drop the notes describing
them as experimental now that they are part of the spec.
Also re-bless the `print` snapshots for the forward tests, which went
stale after rebasing over the printer change that now emits `(param
...)` for imported core functions.
Assisted-by: claude:claude-fable-5-1
Signed-off-by: Roman Volosatovs <rvolosatovs@riseup.net>
Pull in the upstream `test/async/forward.wast` test for the
`{stream,future}.forward` built-ins and regenerate the spec test
wrappers and snapshots.
Assisted-by: claude:claude-fable-5-1
Signed-off-by: Roman Volosatovs <rvolosatovs@riseup.net>
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Dummy modules generated for async exports now import the `[stream-forward-N]` and `[future-forward-N]` intrinsics alongside the other stream/future intrinsics, so the forward name-mangling and encoding paths are exercised by `component embed --dummy`. The affected CLI tests enable `cm-forward` when validating. Signed-off-by: Roman Volosatovs <rvolosatovs@riseup.net>
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Add support for
{stream,future}.forwardbuiltins as specified in WebAssembly/component-model#717