Changes in component.rs

1b59b579 - Add support for map type (#12216)

Mon, 09 Mar 2026 23:34:21 +0000

Add support for map type (#12216)* Add support for map typeSigned-off-by: Yordis Prieto * Add Map and MapEntry classes to support key/value pairs in component modelThis commit introduces the Map and MapEntry classes, enabling the representation of map values in the component model. The Map class allows for the creation and iteration of key/value pairs, enhancing the functionality of the wasmtime component API. Additionally, the .gitignore file is updated to exclude build artifacts from the crates/c-api directory.* Add wasm_component_model_map configuration support* Format code* Format C code* Enhance component model to support HashMap typeThis commit introduces support for HashMap in the component model, allowing maps to be represented as list> in the canonical ABI. It includes implementations for the ComponentType, Lower, and Lift traits for HashMap, enabling type checking, lowering to flat representations, and lifting from memory. Additionally, the maximum depth for type generation in the fuzzing utility is updated to accommodate the new map type.* Refactor component configuration to introduce map supportThis commit removes the previous wasm features configuration and adds new functions for creating a map-configured engine. The `map_config` and `map_engine` functions are introduced to facilitate the use of the component model with maps in tests, ensuring that the engine is properly configured for map types in the component model.* Add new WAST test for map types and remove map type definitions from existing testsThis commit introduces a new WAST test file specifically for testing various map types in the component model. Additionally, it removes the redundant map type definitions from the existing types.wast file to streamline the test suite.* Update component fuzzing and dynamic tests to replace call_and_post_return with call* Format code* Refactor HashMap usage in typed.rs to use wasmtime_environ collections* Fix HashMap initialization and insertion to handle potential errors in typed.rs* Refactor HashMap handling in typed.rs to use lower_map_iter for improved iteration and memory management. Introduce new implementations for ComponentType, Lower, and Lift traits for std::collections::HashMap, enhancing support for map types in the component model.* Fix map adapter trampoline compilation and alignment bugsThe translate_map function had two categories of bugs preventing mapadapter trampolines from working:1. Wasm stack discipline: local_set_new_tmp emits LocalSet which pops from the stack, but was called when the stack was empty (to "pre-allocate" locals). Fixed by computing values first, then calling local_set_new_tmp to consume them—matching translate_list's pattern. Also removed an erroneous LocalTee that left an orphan value on the stack. Affected: src_byte_len, dst_byte_len, cur_src_ptr, cur_dst_ptr.2. Pointer advancement: after value translation, the pointer still points at the value start. The code only advanced by trailing padding instead of value_size + trailing_padding, causing every loop iteration to re-read the same memory.Also fixes entry layout to use proper record alignment rules (entryalign = max(key_align, value_align), value at aligned offset).* Refactor map entry layout calculations to use canonical ABI* Remove unnecessary clone of map pairs during loweringVal::Map already holds Vec<(Val, Val)> which derefs to &[(Val, Val)],matching lower_map's signature directly. The intermediate Vec allocationand deep clone of every key/value pair was redundant.* Deduplicate map lift logic between HashMap implementations* Deduplicate list and map sequence translation scaffolding* Fix cargo fmt formatting issues* Deduplicate map typecheck logic* Deduplicate map lowering with linear_lower_map_to_flat and linear_lower_map_to_memory helpers* Clean up lift_try_map: use drop, move TryHashMap import to module scope* Fix CI: arbtest overflow and no-std HashMap lift_map- component_fuzz: use saturating_sub in generate_hashable_key to prevent underflow when fuel is 0 and Enum variant is chosen- typed: remove incorrect ? operators in lift_map for hashbrown::HashMap (with_capacity and insert don't return Result)* Store map tuple layout in TypeMapCompute map entry ABI and value offsets once during type building, and reuse that metadata in runtime map lift/lower paths instead of recalculating tuple layout at each call site.* Refactor map ABI argument passingBundle map lift/lower layout and type metadata into a small MapAbi32 helper so map helper calls stay concise without changing behavior.* Fix CI: enable component_model_map in fuzzing and handle map in arbitrary_valThe fuzzer's component_api oracle was generating map types but the enginedidn't have the map feature enabled, and arbitrary_val had no arm forType::Map. Enable component_model_map in the store helper (matching howcomponent_model_async is forced on) and implement arbitrary value generationfor map types.---------Signed-off-by: Yordis Prieto List of files: /wasmtime-44.0.1/crates/test-util/src/component.rs

c09aa380 - deprecate `[Typed]Func::post_return[_async]` and make them no-ops (#12498)

Tue, 03 Feb 2026 19:13:45 +0000

deprecate `[Typed]Func::post_return[_async]` and make them no-ops (#12498)* deprecate `[Typed]Func::post_return[_async]` and make them no-opsWith the advent of the Component Model concurrency ABI and it's `task.return`intrinsic, post-return functions have been informally deprecated and areexpected to be removed for WASI 1.0 and the corresponding stable edition of theComponent Model. Consequently, it does not make sense anymore to requireembedders to explicitly call the post-return function after using`[Typed]Func::call[_async]`.As of this commit, `[Typed]Func::post_return[_async]` are no-ops. Instead, thepost-return function is called automatically as part of`[Typed]Func::call[_async]` if present, which is how`[Typed]Func::call_concurrent` has worked all along. In addition, this commitfixes and tests a couple of cases where the task and/or thread was beingdisposed of before the post-return function was called.* address review feedback* test post-return function in more scenariosSpecifically, I've split the `invoke_post_return` test into multiple tests:- using `TypedFunc::call`- using `TypedFunc::call_async` with concurrency support enabled- using `TypedFunc::call_async` with concurrency support disabled- using `Func::call_async` with concurrency support disabled- using `TypedFunc::call_concurrent`* remove GCC/clang-specific deprecation attributeThis broke the MSVC build.* bless bindgen output* remove obsolete post-return functions and fieldsNow that post-return calls are handled internally without requiring explicitaction by the embedder, we can avoid unnecessary bookkeeping. List of files: /wasmtime-44.0.1/crates/test-util/src/component.rs

cc8d04f4 - Remove need for explicit `Config::async_support` knob (#12371)

Fri, 23 Jan 2026 02:46:45 +0000

Remove need for explicit `Config::async_support` knob (#12371)* Refactor component model host function definitionsPush the `async`-ness down one layer.* Remove need for explicit `Config::async_support` knobThis commit is an attempt to step towards reconciling "old async" and"new async" in Wasmtime. The old async style is the original asyncsupport in Wasmtime with `call_async`, `func_wrap_async`, etc, where themain property is that the store is "locked" during an async operation.Put another way, a store can only execute at most one async operation ata time. This is in contrast to "new async" support in Wasmtime with thecomponent-model-async (WASIp3) support, where stores can have more thanone async operation in flight at once.This commit does not fully reconcile these differences, but it doesremove one hurdle along the way: `Config::async_support`. Since thebeginning of Wasmtime this configuration knob has existed to explicitlydemarcate a config/engine/store as "this thing requires `async` stuffinternally." This has started to make less and less sense over timewhere the line between sync and async has become more murky with WASIp3where the two worlds comingle. The goal of this commit is to deprecate`Config::async_support` and make the function not actually do anything.In isolation this can't simply be done, however, because there are manyload-bearing aspects of Wasmtime that rely on this `async_support` knob.For example once epochs + yielding are enabled it's required that allWasm is executed on a fiber lest it hit an epoch and not know how toyield. That means that this commit is not a simple removal of`async_support` but instead a refactoring/rearchitecting of how async isused internally within Wasmtime. The high-level ideas within Wasmtimenow are:* A `Store` has a "requires async" boolean stored within it.* All configuration options which end up requiring async, such as yielding with epochs, turn this boolean on.* Creation of host functions which use async (e.g. `func_wrap_{async,concurrent}`) will also turn this option on.* Synchronous API entrypoints into Wasmtime ensure that this boolean is disabled.* Asynchronous APIs are usable at any time.This means that the concept of an async store vs a sync store is nowgone. All stores are equally capable of executing sync/async, and thechange now is that dynamically some stores will require that async isused with certain configuration. Additionally all panicking conditionsaround `async_support` have been converted to errors instead. Allrelevant APIs already returned an error and things are murky enough nowthat it's not necessarily trivial to get this right at the embedderlevel. In the interest of avoiding panics all detected async mismatchesare now first-class `wasmtime::Error` values.The end result of this commit is that `Config::async_support` is adeprecated `#[doc(hidden)]` function that does nothing. While manyinternal changes happened as well as having new tests for all this sortof behavior this is not expected to have a great impact on externalconsumers. In general a deletion of `async_support(true)` is in theoryall that's required. This is intended to make it easier to think aboutasync/sync/etc in the future with WASIp3 and eventually reconcile`func_wrap_async` and `func_wrap_concurrent` for example. That's leftfor future refactorings however.prtest:full* Review comments* Fix CI failures List of files: /wasmtime-44.0.1/crates/test-util/src/component.rs

162fe0f8 - Migrate test utils to `wasmtime::error` (#12272)

Wed, 07 Jan 2026 22:44:22 +0000

Migrate test utils to `wasmtime::error` (#12272) List of files: /wasmtime-44.0.1/crates/test-util/src/component.rs

cd4657b2 - test-util: Use `wasmtime_environ::error` instead of `anyhow` (#12209)

Mon, 22 Dec 2025 21:24:09 +0000

test-util: Use `wasmtime_environ::error` instead of `anyhow` (#12209)* fix Cargo.toml deps* test-util: Use `wasmtime_environ::error` instead of `anyhow` List of files: /wasmtime-44.0.1/crates/test-util/src/component.rs

b221fca7 - update `component-model-async` plumbing (#11123)

Thu, 03 Jul 2025 22:03:59 +0000

update `component-model-async` plumbing (#11123)* [DO NOT MERGE] update `component-model-async` plumbingThis pulls in the latest Component Model async ABI code from the`wasip3-prototyping` repo, including various API refactors and spec updates.This includes all the changes to the `wasmtime` crate from `wasip3-prototyping`_except_ that the `concurrent` submodule and child submodules contain onlynon-functional stubs. For that reason, and the fact thate.g. `Func::call_async` is now implemented in terms of `Func::call_concurrent`,most of the component model tests are failing. This commit is not meant to bemerged as-is; a follow-up commit (to be PR'd separately) will contain the real`concurrent` implementation, at which point the tests will pass again. I'msplitting these into separate PRs to make review easier.Signed-off-by: Joel Dice * Undo wit-bindgen changesNo longer necessary after other refactors* Move back to crates.io-based wit-bindgen* Undo upgrade of http-body-util(deferred for future PR)* Add back in arbitrary use of asyncLooks like it may have been lost by accident* Make imports more conventional for Wasmtime* Some minor changes* Privatize a component field* Cut down a bit on #[cfg]* Undo a no-longer-necessary `pub`* add doc comments for `{Future,Stream,ErrorContext}Any`Signed-off-by: Joel Dice * rename `concurrent` stub module to `concurrent_disabled`...and avoid panicking in the stubs.Signed-off-by: Joel Dice * fix test regressionSigned-off-by: Joel Dice * revert `call_async` and `post_return_impl` changesThese will need to wait until the `component-model-async` feature is fullyimplemented.Signed-off-by: Joel Dice * remove unused structSigned-off-by: Joel Dice * add `Options::callback` fieldThis isn't used yet, but will be used when the real `component-model-async`implementation is merged.Signed-off-by: Joel Dice * Remove no-longer-needed feature* Trim reexports from WasmtimeSome of these are no longer needed or can be avoided with small changes.Some deps are likely needed in the next commit but they'll be best addedthere.* Update test expectations* More trimming of Cargo.toml* Defer `*Buffer` traits to next PRNot needed for this PR I believe.* Use conventional Wasmtime imports + remove dummy_waker* Reduce duplication in `*_disabled`* Remove some unncessary bounds* Remove some `for<'a>` bounds where unnecessary* Remove another bound* Defer more functions to the next PR`drop_fibers` is different in the next PR, so defer it to then.* Remove some reexports no longer necessaryBindings generation changed awhile back so these aren't needed, deferthe implementations to the next PR.* Remove unnecessary dropThis was already moved to `run_manual_drop_routines`* Defer a `pub(crate)` to a future PR* Expand comments in traphandlers* Defer some types to the next PR* Update linker documentation* Add `Send`/`Sync` bounds to `ComponentType`This commit is extracted from from review of #11123 and #11127. Whilenot literally present in those PRs it's my own personal conclusion thatit's best to just go ahead and add these bounds at the "base" of thecomponent trait hierarchy. The current implementation in #11123 addsbounds in many locations and this would remove the need to add boundseverywhere and instead have everything inherited through the `Lift` and`Lower` traits.This raises the question of: why? The main conclusion that I've reachedleading to this change is that Wasmtime currently will store `R`, areturn value, on the stack during the lowering process back into linearmemory. This might involve allocation, however, meaning that wasm can beinvoked and a context switch could happen. For Wasmtime's `unsafe impl`of `Send` and `Sync` on fibers to be sound it requires that thisstack-local variable is also `Send` and `Sync` as it's an entirelyuser-provided type. Thus I've concluded that for results it's alwaysrequired for these to be both `Send` and `Sync` (or at the very least,`Send`).Given that I've gone ahead and updated to require both `Send` and `Sync`for both params and results. This is not expected to actually have anyimpact in practice since all primitives are already `Send`/`Sync` (minus`Rc` impls all removed here) and all `bindgen!`-generated types arecompositions of `Send`/`Sync` primitives meaning that they're also`Send` and `Sync`.* Remove some now-unnecessary bounds* Fix build after #11160* Remove some now-unnecessary duplicate bounds* Uncomment test that now works* Undo accidental doc wrap* Clarify comment on `Value` typesDon't leave `TODO` in public-facing documentation ideally* Actually resolve the conflict (forgot to commit)* Avoid returning boxed futures in APIs* Defer making constructors more public to a future PR* Make a method name more conventional* Refactor `linear_lift_into_from_memory`* Drop the `max_count` parameter in favor of slicing the `WasmList` itself. Avoids situations such as what happens if `max_count` is larger than the length of the list.* Don't have the default implementation collect to a vector and then push all that onto a different vector. Instead push each item individually through `extend`.* De-indent a block of code added* Remove unsafety from `prepare_call`Mostly move the parameters themselves to the closure to avoid rawpointers/drop/etc.This will have the consequence of in the future `call_async` is going tonow require `Params: 'static` but that seems more-or-less inevitable atthis point.* Go back to returning box, alas.* Apply same treatment to lift functionMake it a closure and reduce some levels of indirection of the variousfunctions in play.* Refactor `lower_params` to require less context.Relax the bounds on the closure specified since it's immediately calledand then additionally take out parameters/captures that the closure cancarry itself.* Don't pass extraneous `Instance` parameterThis can now be inferred from `Func`.* Clean up some SAFETY comments* Generalize the signature of `lift_results`* Move `lift_results` function to `Func`Also rename the lift/lower helpers to `with_{lift,lower}_context`* Remove parameter from `with_lift_context`Like `with_lower_context` this is fine to capture in the closure passedin.* Simplify the dynamic lifting logicDon't call `with_lift_context` in two locations, only call it once witha dynamic parameter.* Refactor away the `Func::lift_results_sync` helper* Use `with_lift_context` in `call_raw`* Simplify a call to `Func::call_unchecked_raw`* Ungate `with_lift_context` to fix non-cm-async build* Fix compile (bad cherry-pick conflict resolution)* Use `with_lower_context` in `call_raw`Trying to unify the async/concurrent paths as much as possible.* Move params out of `call_raw`Let closures capture the params, no need to thread it through as anunnecessary argument.* Clean up unsafety in `Func::call_raw`* Accurately mark `call_raw` itself as `unsafe`, then document why callers should be safe.* Don't have one large `unsafe` block in `call_raw`, instead split it up with separate safety comments.* Move a one-off type definition closer to its use* Avoid intermediate allocations in dynamic calls* Simplify a future-return site* Deduplicate checking parameter count* Simplify a future invocation with `?`* Simplify a variable declaration* Simplify some function signatures* Remove outdated safety comment* Refactor to not require `Params: 'static` on `call_async`* Remove no-longer-necessary SAFETY comment* Fix typos* Add a fast-path with no `Box` for sync host functionsSpeeds up host calls by ~20% and puts them back on parity with thebeforehand numbers Wasmtime has.* Synchronize signatures of async/concurrent dynamic callsUse slices for both instead of vecs for one and slices for the other.Required some slight rejiggering. Apparently one can solve a closureproblem with another closure, then one surely has no more closureproblems.* Fix non-cm-async build---------Signed-off-by: Joel Dice Co-authored-by: Alex Crichton List of files: /wasmtime-44.0.1/crates/test-util/src/component.rs

7dba8efd - Rename `Lift` and `Lower` trait methods (#11070)

Fri, 20 Jun 2025 18:52:21 +0000

Rename `Lift` and `Lower` trait methods (#11070)* `Lower::lower` becomes `Lower::linear_lower_to_flat`* `Lower::store` becomes `Lower::linear_lower_to_memory`* `Lift::lift` becomes `Lift::linear_lift_from_flat`* `Lift::load` becomes `Lift::linear_lift_from_memory`This renaming is to distinguish these linear-memory methods from the GC versionsthat will be added in follow up commits.No functional changes here, just renaming. List of files: /wasmtime-44.0.1/crates/test-util/src/component.rs

ca7081a2 - Consolidate "util" crates for testing (#10423)

Thu, 20 Mar 2025 15:08:47 +0000

Consolidate "util" crates for testing (#10423)* Consolidate "util" crates for testingThis commit consolidates all of the existing crates we have for testinginto a smaller set of crates. Specifically:* `crates/misc/component-fuzz-util` => `wasmtime-test-util` + `component-fuzz` feature* `crates/misc/component-test-util` => `wasmtime-test-util` + `component` feature* `crates/wast-util` => `wasmtime-test-util` + `wast` feature* `crates/misc/component-macro-test` => `wasmtime-test-macros`The goal is to have one location we put various test helpers/macrosrather than our current organically-grown many locations. This isinspired by the test failure on #10405 where I'd like to refactor moreinfrastructure to a "test util" location but it wasn't clear where toput it so I wanted to do this refactoring first.* Remove unused file List of files: /wasmtime-44.0.1/crates/test-util/src/component.rs