feat(wasi): component directory enumeration under --wasi-fs (SR-39, closes #405) - #409
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…loses #405) After SR-37 (get-directories) and SR-38 (file read), a preview2 component read a file end-to-end but std::fs::read_dir still failed: open-at(dir) then wasi:filesystem/types::[method]descriptor.read-directory hit [Runtime][E07DA] Function not found in exports. Both read-directory and directory-entry-stream.read-directory-entry were unimplemented — no dispatch_core handler and no wasip2_host signature, so the calls fell through. Implemented directory enumeration: - descriptor.read-directory(self) -> result<directory-entry-stream, error-code>: snapshots std::fs::read_dir entries as (descriptor-type, name) with a cursor, keyed by a fresh stream handle (`.`/`..` excluded, matching preview2). - directory-entry-stream.read-directory-entry(self) -> result<option<directory-entry>, error-code> where directory-entry = record { type: descriptor-type, name: string }: returns the next entry (name in a fresh cabi_realloc'd guest buffer via the SR-38 on-demand mechanism, extended to read-directory-entry with a filename-sized buffer) or none at end. - Signatures added to wasip2_host.rs; the record is modelled as Tuple(U8, String) and the enum as U8, which lower_results_to_retptr already lowers correctly (Result -> Option -> Tuple -> {u8 padded to 4, string ptr+len}). Verified end-to-end: kilnd now matches `wasmtime run --dir .::.` for both READ:CANARY and DIR:[...] (single- and multi-entry dirs incl. a subdir). Unit oracle read_directory_enumerates_entries_then_none asserts enumeration + none. Also: added serial_test as a kiln-wasi dev-dependency and marked the 5 new SR-37/38/39 dispatcher tests #[serial_test::serial] — they build a WasiDispatcher that draws the global capability budget, which contends under parallel test runs. A broader pre-existing flakiness in the same suite (unrelated capability tests) is filed separately as SR-40. Trace: SR-39
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avrabe
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…) (#410) Version bump 0.4.0 → 0.4.1. Ships the complete component filesystem read/list fix for WASI Preview2 components under kilnd --wasi --component --wasi-fs: - SR-37 (#406): get-directories returns a guest-usable preopen list. - SR-38 (#407): file read (blocking-read) returns bytes in a guest-owned buffer with offset/EOF tracking. - SR-39 (#409): directory enumeration (read-directory / read-directory-entry). Together these make a preview2 component read and list files under a preopen, matching `wasmtime run --dir`. Closes #405. Trace: SR-39
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What
Third and final layer of #405. After SR-37 (get-directories, #406) and SR-38 (file read, #407), a preview2 component could read a file but
std::fs::read_dirstill crashed with[Runtime][E07DA] Function not found in exports:descriptor.read-directoryanddirectory-entry-stream.read-directory-entrywere unimplemented (no handler, no signature).Fix
descriptor.read-directory→result<directory-entry-stream, error-code>: snapshotsstd::fs::read_direntries as(descriptor-type, name)with a cursor, keyed by a fresh stream handle (./..excluded, matching preview2).directory-entry-stream.read-directory-entry→result<option<directory-entry>, error-code>wheredirectory-entry = record { type, name }: returns the next entry (name in a freshcabi_realloc'd guest buffer via SR-38's on-demand mechanism, extended to this call) ornoneat end.wasip2_host.rs; the record is modelled asTuple(U8, String)and the enum asU8, whichlower_results_to_retptralready lowers correctly.Verification
wasmtime run --dir .::.for bothREAD:CANARYandDIR:[…]— single-entry and a multi-entry dir with a subdir (types + ordering match).read_directory_enumerates_entries_then_none(// rivet: verifies SR-39).Also
Added
serial_testas a kiln-wasi dev-dep and marked the 5 SR-37/38/39 dispatcher tests#[serial_test::serial](they draw the global capability budget). A broader pre-existing flakiness in the same suite (unrelated capability tests, confirmed on clean main) is filed as SR-40 — not fixed here.Closes #405.
Trace: SR-39
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