Particularly useful in our tests, where we don't have the regular console
logging with post-facto object inspection, and instead need to provide all this
info up front.
The last write accidentally wasn't accounted for in the returned length
of the string and we unfortunately don't have any test coverage of
`encodeInto` since it requires Firefox nightly right now (and doesn't
work in Node yet).
Closes#1436
This commit adds an intrinsics to the `wasm_bindgen` crate which
accesses the `WebAssembly.Table` which is the function table of the
module. Eventually the thinking is that a module would import its own
function table via native wasm functionality (via `anyref` and such),
but until that's implemented let's add a binding for it ourselves!
Closes#1427
Because of some incorrect use of `js.push_str(..)`, we could sometimes emit code
before the ES modules imports, which is syntactically invalid:
const __exports = {};
import { Thing } from '...'; // Syntax error!
This has been fixed by making sure that the correct `imports` or `imports_post`
string is built up. We now also assert that the `js` string is empty at the
location where we add imports if we're using ES modules.
This commit fixes the `init` function when passed a
`WebAssembly.Module`. Upon closer reading of the [spec] we see there's
two possible return values from `WebAssembly.instantiate`. If passed a
`Module`, it will return only the `Instance`. If passed a buffer source,
though, it'll return an object with the module/instance.
The fix here is to check the result value is an `Instance`, and if so
assume the input must have been a module so it's paired up in the
output.
Closes#1418
[spec]: http://webassembly.github.io/spec/js-api/index.html#webassembly-namespace
Instead of doubling the size on each iteration, use precise upper limit (3 * JS length) if the string turned out not to be ASCII-only. This results in maximum of 1 reallocation instead of O(log N).
Some dummy examples of what this would change:
- 1000 of ASCII chars: no change, allocates 1000 bytes and bails out.
- 1000 ASCII chars + 1 '😃': before allocated 1000 bytes and reallocated to 2000; now allocates 1000 bytes and reallocates to 1006.
- 1000 of '😃' chars: before allocated 1000 bytes, reallocated to 2000, finally reallocated again to 4000; now allocates 1000 bytes and reallocates to 4000 right away.
Related issue: #1313
All numbers in WebAssembly are signed and then each operation on them
may optionally have an unsigned version. This means that when we pass
large signed numbers to JS they actually show up as large negative
numbers even though JS numbers can faithfully represent the type.
This is fixed by adding `>>>0` in a few locations in the generated
bindings to coerce the JS value into an unsigned value.
Closes#1388
Aside from visual deduplication, this actually fixes a bug in js2rust.rs where it didn't call `expose_is_like_none` but used `isLikeNone` inside of `arg.get_64()` branch.
Most of the CLI crates were already in the 2018 edition, and it turns
out that one of the macro crates was already in the 2018 edition so we
may as well move everything to the 2018 edition!
Always nice to remove those `extern crate` statements nowadays!
This commit also does a `cargo fmt --all` to make sure we're conforming
with style again.
Node.js doesn't currently implement `TextEncoder::encodeInto`. I've raised an upstream issue to add it - https://github.com/nodejs/node/issues/26904 - but it's likely to take some time and will be available only in new releases.
In the meanwhile, it's worth noting that Node.js already has `Buffer::write` which has pretty similar semantics, but doesn't require creating an intermediate view using `.subarray` and instead accepts pointer and length directly.
Also, Node.js has `Buffer::byteLength` helper which allows to efficiently retrieve an encoded byte length of a string upfront, and so allows us to avoid a loop with reallocations.
This change takes leverage of these methods by generating an additional Buffer-based view into the WASM memory and using it for string operations.
I'm seeing up to 35% increase in performance in string-heavy library benchmarks.
We have very few tests today so this starts to add the basics of a test
suite which compiles Cargo projects on-the-fly which will hopefully help
us bolster the amount of assertions we can make about the output.
This commit implements [RFC 8], which enables transitive and transparent
dependencies on NPM. The `module` attribute, when seen and not part of a
local JS snippet, triggers detection of a `package.json` next to
`Cargo.toml`. If found it will cause the `wasm-bindgen` CLI tool to load
and parse the `package.json` within each crate and then create a merged
`package.json` at the end.
[RFC 8]: https://github.com/rustwasm/rfcs/pull/8
This commit fixes an erroneous use-after-free which can happen in
erroneous situations in JS. It's intended that if you invoke a closure
after its environment has been destroyed that you'll immediately get an
error from Rust saying so. The JS binding generation for mutable
closures, however, accidentally did not protect against this.
Each closure has an internal reference count which is incremented while
being invoked and decremented when the invocation finishes and also when
the `Closure` in Rust is dropped. That means there's two branches where
the reference count reaches zero and the internal pointer stored in JS
needs to be set to zero. Only one, however, actually set the pointer to
zero!
This means that if a closure was destroyed while it was being invoked it
would not correctly set its internal pointer to zero. A further
invocation of the closure would then pass as seemingly valid pointer
into Rust, causing a use-after-free.
A test isn't included here specifically for this because our CI has
started failing left-and-right over this test, so this commit will
hopefully just make our CI green!
We've always wanted this to be the deterministic, but usage of `HashMap`
for example can accidentally lead to non-determinism. Looks like one was
forgotten and the bindings were nondeterministic by accident as a
result!
This commit deprecates the `--web`, `--no-modules`, and `--nodejs` flags
in favor of one `--target` flag. The motivation for this commit is to be
consistent between `wasm-bindgen` and `wasm-pack` so documentation for
one is applicable for the other (so we don't have to document everywhere
what the translation is between flags). Additionally this should make it
a bit easier to add new targets (if necessary) in the future as it won't
add to the proliferation of flags.
For now the old flags (like `--web`) continue to be accepted, but
they'll be removed during the next set of breaking changes for
`wasm-bindgen`.
This allows subverting the checks and resolution performed by the
`module` attribute added as part of [RFC 6] and has been discussed in #1343.
Closes#1343
[RFC 6]: https://github.com/rustwasm/rfcs/pull/6
This commit reverts part of the implementation of [RFC 6]. That RFC
specified that the `--browser` flag was going to be repurposed for the
new "natively loadable as ES module output", but unfortunately the
breakage is far broader than initially expected. It turns out that
`wasm-pack` passes `--browser` by default which means that a change to
break `--browser` would break all historical versions of `wasm-pack`
which is a bit much for now.
To solve this the `--browser` flag is going back to what it represents
on the current released version of `wasm-bindgen` (optimize away some
node.js checks in a few places for bundler-style output) and a new
`--web` flag is being introduced as the new deployment strategy.
[RFC 6]: https://github.com/rustwasm/rfcs/pull/6Closes#1318
This commit is an implementation of [RFC 6] which enables crates to
inline local JS snippets into the final output artifact of
`wasm-bindgen`. This is accompanied with a few minor breaking changes
which are intended to be relatively minor in practice:
* The `module` attribute disallows paths starting with `./` and `../`.
It requires paths starting with `/` to actually exist on the filesystem.
* The `--browser` flag no longer emits bundler-compatible code, but
rather emits an ES module that can be natively loaded into a browser.
Otherwise be sure to check out [the RFC][RFC 6] for more details, and
otherwise this should implement at least the MVP version of the RFC!
Notably at this time JS snippets with `--nodejs` or `--no-modules` are
not supported and will unconditionally generate an error.
[RFC 6]: https://github.com/rustwasm/rfcs/pull/6Closes#1311
Looks like `TextEncoder#encodeInto` isn't compatible when the buffer
passed in is backed by a `SharedArrayBuffer`, so if the module has a
shared thread skip the `encodeInto` optimization entirely.
This commit adds support for the recently implemented standard of
[`TextEncoder#encodeInto`][standard]. This new function is a "bring your
own buffer" style function where we can avoid an intermediate allocation
and copy by encoding strings directly into wasm's memory.
Currently we feature-detect whether `encodeInto` exists as it is only
implemented in recent browsers and not in all browsers. Additionally
this commit emits the binding using `encodeInto` by default, but this
requires `realloc` functionality to be exposed by the wasm module.
Measured locally an empty binary which takes `&str` previously took
7.6k, but after this commit takes 8.7k due to the extra code needed for
`realloc`.
[standard]: https://encoding.spec.whatwg.org/#dom-textencoder-encodeintoCloses#1172
This commit adds experimental support to `wasm-bindgen` to emit and
leverage the `anyref` native wasm type. This native type is still in a
proposal status (the reference-types proposal). The intention of
`anyref` is to be able to directly hold JS values in wasm and pass the
to imported functions, namely to empower eventual host bindings (now
renamed WebIDL bindings) integration where we can skip JS shims
altogether for many imports.
This commit doesn't actually affect wasm-bindgen's behavior at all
as-is, but rather this support requires an opt-in env var to be
configured. Once the support is stable in browsers it's intended that
this will add a CLI switch for turning on this support, eventually
defaulting it to `true` in the far future.
The basic strategy here is to take the `stack` and `slab` globals in the
generated JS glue and move them into wasm using a table. This new table
in wasm is managed at the fringes via injected shims. At
`wasm-bindgen`-time the CLI will rewrite exports and imports with shims
that actually use `anyref` if needed, performing loads/stores inside the
wasm module instead of externally in the wasm module.
This should provide a boost over what we have today, but it's not a
fantastic strategy long term. We have a more grand vision for `anyref`
being a first-class type in the language, but that's on a much longer
horizon and this is currently thought to be the best we can do in terms
of integration in the near future.
The stack/heap JS tables are combined into one wasm table. The stack
starts at the end of the table and grows down with a stack pointer (also
injected). The heap starts at the end and grows up (state managed in
linear memory). The anyref transformation here will hook up various
intrinsics in wasm-bindgen to the runtime functionality if the anyref
supoprt is enabled.
The main tricky treatment here was applied to closures, where we need JS
to use a different function pointer than the one Rust gives it to use a
JS function pointer empowered with anyref. This works by switching up a
bit how descriptors work, embedding the shims to call inside descriptors
rather than communicated at runtime. This means that we're accessing
constant values in the generated JS and we can just update the constant
value accessed.
LLVM's mergefunc pass may mean that the same descriptor function is used
for different closure invocation sites even when the closure itself is
different. This typically only happens with LTO but in theory could
happen at any time!
The assert was tripping when we tried to delete the same function table
entry twice, so instead of a `Vec<usize>` of entries to delete this
commit switches to a `HashSet<usize>` which should do the deduplication
for us and enusre that we delete each descriptor only once.
Closes#1264
We've had a lot of bug reports with upstream webpack currently and while
webpack has a fix it may take a moment to deploy. Let's try and fix
wasm-bindgen in the meantime!
Once webpack is updated we can go back to emitting a producers section
by default and publish a new version of wasm-bindgen.
This should help handle instances like the recent Webpack bug and is
also a useful flag in its own right. For now it's set to `false`, but if
the Webpack bug persists through to tomorrow we likely want to publish a
version of `wasm-bindgen` with it default set to `true`.
This commit moves `wasm-bindgen` the CLI tool from internally using
`parity-wasm` for wasm parsing/serialization to instead use `walrus`.
The `walrus` crate is something we've been working on recently with an
aim to replace the usage of `parity-wasm` in `wasm-bindgen` to make the
current CLI tool more maintainable as well as more future-proof.
The `walrus` crate provides a much nicer AST to work with as well as a
structured `Module`, whereas `parity-wasm` provides a very raw interface
to the wasm module which isn't really appropriate for our use case. The
many transformations and tweaks that wasm-bindgen does have a huge
amount of ad-hoc index management to carefully craft a final wasm
binary, but this is all entirely taken care for us with the `walrus`
crate.
Additionally, `wasm-bindgen` will ingest and rewrite the wasm file,
often changing the binary offsets of functions. Eventually with DWARF
debug information we'll need to be sure to preserve the debug
information throughout the transformations that `wasm-bindgen` does
today. This is practically impossible to do with the `parity-wasm`
architecture, but `walrus` was designed from the get-go to solve this
problem transparently in the `walrus` crate itself. (it doesn't today,
but this is planned work)
It is the intention that this does not end up regressing any
`wasm-bindgen` use cases, neither in functionality or in speed. As a
large change and refactoring, however, it's likely that at least
something will arise! We'll want to continue to remain vigilant to any
issues that come up with this commit.
Note that the `gc` crate has been deleted as part of this change, as the
`gc` crate is no longer necessary since `walrus` does it automatically.
Additionally the `gc` crate was one of the main problems with preserving
debug information as it often deletes wasm items!
Finally, this also starts moving crates to the 2018 edition where
necessary since `walrus` requires the 2018 edition, and in general it's
more pleasant to work within the 2018 edition!
This commit updates the `--debug` output of `wasm-bindgen` from the CLI
to catch all JS exceptions from imported functions, log such, and then
rethrow. It's hoped that this can be used when necessary to learn more
information about thrown exceptions and where an uncaught exception
could be causing issues with Rust code.
Closes#1176
Throw it in an `Option` and then `take()` it when we consume it to
ensure that future calls to insert data into it panic instead of
producing inconsistent JS.
We might gc a table away so if we need to export it be sure to do so
before we gc! Additionally remove an extraneous gc that snuck in at some
point, no need to do more than one.
Closes#1130
Turns out `heap.fill(undefined)` is required to ensure it's a dense
array, otherwise we'll accidentally be a sparse array and much slower
than necessary!
This commit switches strategies for storing `JsValue` from a heap/stack
to just one heap. This mirrors the new strategy for `JsValue` storage
in #1002 and should make multiplexing those strategies at
`wasm-bindgen`-time much easier.
Instead of having one array which acts as a stack for borrowed values
and one array for a heap of borrowed values, only one JS array is used
for storage of JS values now. This makes `getObject` far simpler by
simply being an array access, but it means that cloning an object now
reserves a new slot instead of reference counting it. If the old
reference counting behavior is needed it's thought that `Rc<JsValue>`
can be used in Rust.
The new "heap" has an initial stack pointer which grows downwards, and a
heap which grows upwards. The heap is a singly-linked-list which is
allocated/deallocated from. The stack grows downwards to zero and
presumably starts generating errors once it underflows. An initial stack
size of 32 is chosen as that should encompass all use cases today, but
we can eventually probably add configuration for this!
Note that the heap is initialized to all `null` for the stack and then
the initial JS values (`undefined`, `null`, `true`, `false`) are pushed
onto the heap in reserved locations.
Previously `catch` and `variadic` would exopse methods in our JS shims,
but they did so earlier than necessary. Turns out `variadic` didn't
actually need to expose anything and `catch` could do so much later!
Currently closure shims are communicated to JS at runtime, although at
runtime the same constant value is always passed to JS! More pressing,
however, work in #1002 requires knowledge of closure descriptor indices
at `wasm-bindgen` time which is not currently known.
Since the closure descriptor shims and such are already constant values,
this commit moves the descriptor function indices into the *descriptor*
for a closure/function pointer. This way we can learn about these values
at `wasm-bindgen` time instead of only knowing them at runtime.
This should have no semantic change on users of `wasm-bindgen`, although
some closure invocations may be slightly speedier because there's less
arguments being transferred over the boundary. Overall though this will
help #1002 as the closure shims that the Rust compiler generates may not
be the exact ones we hand out to JS, but rather wrappers around them
which do `anyref` business things.
This commit fixes a case in `wasm2es6js` where if an imported function
was reexported it wasn't handled correctly. This doesn't have a direct
test but came up during the development of #1002
This is split out from #1002 and is intended to fix the tool's handling
of the `start` function. For the most accurate emulation of the wasm ESM
spec I believe we need to defer execution of the start function until
all our exports are wired up which should allow valid cyclical
references during instantiation.
The fix here is to remove the start function, if one is present, and
inject an invocation of it at the end of initialization (after our
exports are wired up). This fixes tests on #1002, but doesn't have any
direct analogue for tests here just yet.
Along the way because multiple files now come out of `wasm2es6js` by
default I've added an `--out-dir` argument as well as `-o` to ensure
that a folder for all outputs can be specified.
This commit adds a new attribute to `#[wasm_bindgen]`: `start`. The
`start` attribute can be used to indicate that a function should be
executed when the module is loaded, configuring the `start` function of
the wasm executable. While this doesn't necessarily literally configure
the `start` section, it does its best!
Only one crate in a crate graph may indicate `#[wasm_bindgen(start)]`,
so it's not recommended to be used in libraries but only end-user
applications. Currently this still must be used with the `crate-type =
["cdylib"]` annotation in `Cargo.toml`.
The implementation here is somewhat tricky because of the circular
dependency between our generated JS and the wasm file that we emit. This
circular dependency makes running initialization routines (like the
`start` shim) particularly fraught with complications because one may
need to run before the other but bundlers may not necessarily respect
it. Workarounds have been implemented for various emission strategies,
for example calling the start function directly after exports are wired
up with `--no-modules` and otherwise working around what appears to be
a Webpack bug with initializers running in a different order than we'd
like. In any case, this in theory doesn't show up to the end user!
Closes#74
This generates a `*.d.ts` file for the wasm file that wasm-bindgen emits
whenever typescript is enable *in addition* to the `*.d.ts` file that
already exists for the JS shim.
Closes#1040
Recently proposed in WebAssembly/tool-conventions#65 each wasm file will
now have an optional `producers` section listing the tooling that went
into producing it. Let's add `wasm-bindgen` in when it processes a wasm
file!
This commit adds an optimization to `wasm-bindgen` to directly import
and invoke other modules' functions from the wasm module, rather than
going through a shim in the imported bindings. This will be an important
optimization in the future for the host bindings proposal, but for now
it's largely just a proof-of-concept to show that we can do it and is
unlikely to bring about many performance benefits.
The implementation in this commit is largely refactoring to reorganize a
bit how functions are imported, but the implementation happens in
`generate_import_function`.
With this commit, 71/287 imports in the `tests/wasm/main.rs` suite get
hooked up directly to the ES modules, no shims needed!
When returning a ptr/length for allocations and such wasm-bindgen's
generated JS would previously return an array with two elements. It
turns out this doesn't optimize well in all engines! (See #1031). It
looks like we can optimize the array destructuring a bit more, but this
is all generated code which doesn't need to be too readable so we can
also remove the temporary allocation entirely and just pass the second
element of this array through a global instead of the return value.
Closes#1031
This fixes a mistake in allowing a `WebAssembly.Module` to be passed to
the initialization function in `--no-modules` mode by ensuring that it
resolves to a map of an instance/module instead of just resolving to an
instance.
This commit adds a `--remove-name-section` flag to the `wasm-bindgen`
command which will remove the `name` section of the wasm file, used to
indicate the names of functions typically used in debugging. This flag
is off-by-default and will primarily be controlled by wasm-pack,
typically being passed by default with `wasm-pack build --release`.
Closes#1021
This commit removes shims, where possible, for `structural` items.
Instead of generating code that looks like:
const target = function() { this.foo(); };
exports.__wbg_thing = function(a) { target.call(getObject(a)); };
we now instead generate:
exports.__wbg_thing = function(a) { getObject(a).foo(); };
Note that this only applies to `structural` bindings, all default
bindings (as of this commit) are still using imported targets to ensure
that their binding can't change after instantiation.
This change was [detailed in RFC #5][link] as an important optimization
for `structural` bindings to ensure they've got performance parity with
today's non-`structural` default bindings.
[link]: https://rustwasm.github.io/rfcs/005-structural-and-deref.html#why-is-it-ok-to-make-structural-the-default
... and add a parallel raytracing demo!
This commit adds enough support to `wasm-bindgen` to produce a workable
wasm binary *today* with the experimental WebAssembly threads support
implemented in Firefox Nightly. I've tried to comment what's going on in
the commits and such, but at a high level the changes made here are:
* A new transformation, living in a new `wasm-bindgen-threads-xform`
crate, prepares a wasm module for parallel execution. This performs a
number of mundane tasks which I hope to detail in a blog post later on.
* The `--no-modules` output is enhanced with more support for when
shared memory is enabled, allowing passing in the module/memory to
initialize the wasm instance on multiple threads (sharing both module
and memory).
* The `wasm-bindgen` crate now offers the ability, in `--no-modules`
mode, to get a handle on the `WebAssembly.Module` instance.
* The example itself requires Xargo to recompile the standard library
with atomics and an experimental feature enabled. Afterwards it
experimentally also enables threading support in wasm-bindgen.
I've also added hopefully enough CI support to compile this example in a
builder so we can upload it and poke around live online. I hope to
detail more about the technical details here in a blog post soon as
well!
I've noticed this in a few cases where it's sometimes easy to have a
`WebAssembly.Module` on-hand for the `--no-modules` mode where you don't
want to necessarily `fetch`. This commit changes the exported
initialization function in `--no-modules` mode to support both!
This commit migrates away from using Serde for the custom section in
wasm executables. This is a refactoring of a purely-internal data
structure to `wasm-bindgen` and should have no visible functional change
on users.
The motivation for this commit is two fold:
* First, the compile times using `serde_json` and `serde_derive` for the
syntax extension isn't the most fun.
* Second, eventually we're going to want to stablize the layout of the
custom section, and it's highly unlikely to be json!
Primarily, though, the intention of this commit is to improve the
cold-cache compile time of `wasm-bindgen` by ensuring that for new users
this project builds as quickly as possible. By removing some heavyweight
dependencies from the procedural macro, `serde`, `serde_derive`, and
`serde_json`, we're able to get a pretty nice build time improvement for
the `wasm-bindgen` crate itself:
| | single-core build | parallel build |
|-------------|-------------------|----------------|
| master | 36.5s | 17.3s |
| this commit | 20.5s | 11.8s |
These are't really end-all-be-all wins but they're much better
especially on the spectrum of weaker CPUs (in theory modeled by the
single-core case showing we have 42% less CPU work in theory).
This commit fixes instantiation of the wasm module even if some of the
improted APIs don't exist. This extends the functionality initially
added in #409 to attempt to gracefully allow importing values from the
environment which don't actually exist in all contexts. In addition to
nonexistent methods being handled now entire nonexistent types are now
also handled.
I suspect that eventually we'll add a CLI flag to `wasm-bindgen` to say
"I assert everything exists, don't check it" to trim out the extra JS
glue generated here. In the meantime though this'll pave the way for a
wasm-bindgen shim to be instantiated in both a web worker and the main
thread, while using DOM-like APIs only on the main thread.
The bindings generation for a class would accidentally omit the `__wrap`
function if it was only discovered very late in the process that
`__wrap` was needed, after we'd already passed the point where we needed
to have decided that.
This commit moves struct field generation of bindings much earlier in
the binding generation process which should ensure everything is all
hooked up by the time we generate the classes themselves.
Closes#949
The `wasm-bindgen` crate is effectively the only user of this crate now
that the `wasm-gc` tool has been deprecated. It's also much easier to
keep it in this repository as it's easier to sync changes to
`parity-wasm`. I'd also like to start refactoring out utilities for
managing a `parity_wasm::Module` to share between this crate and the
other CLI support code.
This commit does a few things, including:
* Fixing the generated JS of `wasm-bindgen` to allow polyfills to work.
(a minor tweak of the generated JS)
* All examples are updated to include a Webpack-specific polyfill for
these two types to get examples working in Edge.
* A new page has been added to the guide about supported browsers. This
mentions known caveats like IE 11 requiring `wasm2js` as well as
documenting some `TextEncoder` and `TextDecoder` workarounds for Edge.
Closes#895
This commit improves the codegen for `Closure<T>`, primarily for ZST
where the closure doesn't actually capture anything. Previously
`wasm-bindgen` would unconditionally allocate an `Rc` for a fat pointer,
meaning that it would always hit the allocator even when the `Box<T>`
didn't actually contain an allocation. Now the reference count for the
closure is stored on the JS object rather than in Rust.
Some more advanced tests were added along the way to ensure that
functionality didn't regress, and otherwise the calling convention for
`Closure` changed a good deal but should still be the same user-facing.
The primary change was that the reference count reaching zero may cause
JS to need to run the destructor. It simply returns this information in
`Drop for Closure` and otherwise when calling it now also retains a
function pointer that runs the destructor.
Closes#874
This commit implements support for binding APIs that take
`Uint8ClampedArray` in JS. This is pretty rare but comes up in a
`web-sys` binding or two, and we're now able to bind these APIs instead
of having to omit the bindings.
The `Uint8ClampedArray` type is bound by using the `Clamped` marker
struct in Rust. For example this is declaring a JS API that takes
`Uint8ClampedArray`:
use wasm_bindgen::Clamped;
#[wasm_bindgen]
extern {
fn takes_clamped(a: Clamped<&[u8]>);
}
The `Clamped` type currently only works when wrapping the `&[u8]`, `&mut
[u8]`, and `Vec<u8>` types. Everything else will produce an error at
`wasm-bindgen` time.
Closes#421
All these functions are now provided by upstream compiler-builtins, so
there's no need for us to be binding them automatically. The remaining
`Math_*` functions are also no longer needed on nightly after
https://github.com/rust-lang/rust/pull/54257 but that PR isn't on beta,
so we'll need to leave these here for awhile while beta rides the trains
This commit removes the need for an injected `ConstructorToken` type and
also cleans up the story we have for generating constructors a bit.
After this commit a `constructor()` is omitted entirely if we're in
non-debug mode and there's no actual listed constructor. Additionally we
don't deal with splat arguments and rerouting constructors, Nick was
kind enough to enlighten me about `Object.create` which is creating an
instance without running the constructor!
Instances of an exported type are now created through one of two
methods:
* If `#[wasm_bindgen(constructor)]` is present, then a `constructor` is
generated with the appropriate signature. If a constructor is not
present and we're in debug mode, a throwing constructor is generated.
If we're in release mode and there's no constructor, no constructor is
generated.
* Otherwise if a binding returns an instance of a type (or otherwise
needs to manfuacture an instance, then it will cause an internal
`__wrap` function to be generated. This function will use
`Object.create` to create an instance without running the constructor.
This should ideally clean up our generated JS for classes quite a bit,
making it much more lean-and-mean!
Previously `wasm-bindgen` would take its `breaks_if_inlined` shims and
attempt to remove them entirely, replacing calls to `breaks_if_inlined`
to the imported closure factories. This worked great in that it would
remove the `breaks_if_inlined` funtion entirely, removing the "cost" of
the `#[inline(never)]`.
Unfortunately as #864 discovered this is "too clever by half". LLVM's
aggressive optimizations won't inline `breaks_if_inlined`, but it may
still change the ABI! We can't replace calls to `breaks_if_inlined` if
the signature changes, because the function its calling has a fixed signature.
This commit cops out a bit and instead of replacing calls to
`breaks_if_inlined` to the imported closure factories, we instead
rewrite calls to `__wbindgen_describe_closure` to the closure factories.
This means that the `breaks_if_inlined` shims do not get removed. It
also means that the closure factory shims have a third and final
argument (what would be the function pointer of the descriptor function)
which is dead and unused.
This should be a functional solution for now and let us iterate on a
true fix later on (if needed). For now the cost of this
`#[inline(never)]` and the extra unused argument should be quite small.
Closes#864
This commit adds support for exporting a function defined in Rust that returns a
`Result`, translating the `Ok` variant to the actual return value and the `Err`
variant to an exception that's thrown in JS.
The support for return types and descriptors was rejiggered a bit to be a bit
more abstract and more well suited for this purpose. We no longer distinguish
between functions with a return value and those without a return value.
Additionally a new trait, `ReturnWasmAbi`, is used for converting return values.
This trait is an internal implementation detail, however, and shouldn't surface
itself to users much (if at all).
Closes#841
This is intended to address #834 where we don't actually want methods scoped
like this! Instead we'll provide one unique accessor for the `window` object
itself.
This resulted in trailing whitespace in the generated file. In addition
to wasting space in a file that gets served over the wire, this also
gets highlighted as a problem when reviewing the generated file in an
editor that highlights trailing whitespace.
The output using modules already uses string formatting that carefully
avoids emitting leading and trailing blanks; adjust the --no-modules
output to match.
This commit adds an implementation of `AsRef<JsValue>` for the `Closure<T>`
type. Previously this was not possible because the `JsValue` didn't actually
exist until the closure was passed to JS, but the implementation has been
changed to ... something a bit more unconventional. The end result, however, is
that `Closure<T>` now always contains a `JsValue`.
The end result of this work is intended to be a precursor to binding callbacks
in `web-sys` as `JsValue` everywhere but still allowing usage with `Closure<T>`.
This commit adds further support for the `Global` attribute to not only emit
structural accessors but also emit functions that don't take `&self`. All
methods on a `[Global]` interface will not require `&self` and will call
functions and/or access properties on the global scope.
This should enable things like:
Window::location() // returns `Location`
Window::fetch(...) // invokes the `fetch` function
Closes#659
We currently pass a raw view into wasm's memory for `getStringFromWasm`, but if
the memory is actually shared then `TextDecoder` rejects `SharedArrayBuffer` and
won't actually decode anything. Work around this for now with an extra copy into
a local buffer, and then pass that buffer to `getStringFromWasm` whenever memory
is shared.
In addition to closing #495 this'll be useful eventually when instantiating
multiple wasm modules from Rust as you'd now be able to acquire a reference to
the current module in Rust itself.
The default of Rust wasm binaries is to export the memory that they contain, but
LLD also supports an `--import-memory` option where memory is imported into a
module instead. It's looking like importing memory is along the lines of how
shared memory wasm modules will work (they'll all import the same memory).
This commit adds support to wasm-bindgen to support modules which import memory.
Memory accessors are tweaked to no longer always assume that the wasm module
exports its memory. Additionally JS bindings will create a `memory` option
automatically because LLD always imports memory from an `env` module which won't
actually exist.
This is a pretty heavyweight dependency which accounts for a surprising amount
of runtime for larger modules in `wasm-bindgen`. We don't need 90% of the crate
and so this commit bundles a small interpreter for instructions we know are only
going to appear in describe-related functions.
This commit adds experimental support for `WeakRef` to be used to automatically
free wasm objects instead of having to always call the `free` function manually.
Note that when enabled the `free` function for all exported objects is still
generated, it's just optionally invoked by the application.
Support isn't exposed through a CLI flag right now due to the early stages of
the `WeakRef` proposal, but the env var `WASM_BINDGEN_WEAKREF` can be used to
enable this generation. Upon doing so the output can then be edited slightly as
well to work in the SpiderMonkey shell and it looks like this is working!
Closes#704
This commit implements the `JsCast` trait automatically for all imported types
in `#[wasm_bindgen] extern { ... }` blocks. The main change here was to generate
an `instanceof` shim for all imported types in case it's needed.
All imported types now also implement `AsRef<JsValue>` and `AsMut<JsValue>`
First added in #161 this never ended up panning out, so let's remove the
experimental suport which isn't actually used by anything today and hold off on
any other changes until an RFC happens.
* Tweak the implementation of heap closures
This commit updates the implementation of the `Closure` type to internally store
an `Rc` and be suitable for dropping a `Closure` during the execution of the
closure. This is currently needed for promises but may be generally useful as
well!
* Support asynchronous tests
This commit adds support for executing tests asynchronously. This is modeled
by tests returning a `Future` instead of simply executing inline, and is
signified with `#[wasm_bindgen_test(async)]`.
Support for this is added through a new `wasm-bindgen-futures` crate which is a
binding between the `futures` crate and JS `Promise` objects.
Lots more details can be found in the details of the commit, but one of the end
results is that the `web-sys` tests are now entirely contained in the same test
suite and don't need `npm install` to be run to execute them!
* Review tweaks
* Add some bindings for `Function.call` to `js_sys`
Name them `call0`, `call1`, `call2`, ... for the number of arguments being
passed.
* Use oneshots channels with `JsFuture`
It did indeed clean up the implementation!
This commit moves the `webidl/tests` folder to a new `crates/webidl-tests` crate
(to have a test-only build script) and ports them to the `#[wasm_bindgen_test]`
attribute, which should hopefully make testing much speedier for execution!
* Fix importing the same identifier from two modules
This needed a fix in two locations:
* First the generated descriptor function needed its hash to include the module
that the import came from in order to generate unique descriptor functions.
* Second the generation of the JS shim needed to handle duplicate identifiers in
a more uniform fashion, ensuring that imported names didn't clash.
* Fix importing the same name in two modules
Previously two descriptor functions with duplicate symbols were emitted, and now
only one function is emitted by using a global table to keep track of state
across macro invocations.
Currently it generates a lot of shim functions which delegate to the wasm module
when loaded, but it turns out with `export let` we can just update the bindings!
Instead of exporting a bunch of shims this updates the export functionality to
only update the `export let` directives with the direct values from the wasm
module once the module is done loading.
In addition to being more ergonomic these are much more efficient at reading
large files as they preallocate internally. This provides a nice speed boost
locally, reducing the overhead of `wasm-bindgen-test-runner` from 0.23s to
0.19s, yay!
This commit updates the test runner to only deserialize a `Module` once and then
directly pass it to the `wasm-bindgen` config, avoiding pulling in a public
dependency with the same strategy as the `wasm-gc-api` crate for now.
This reduces the runtime of this step for `wasm-bindgen-test-runner` from ~0.23s
to ~0.19s on my machine.
Since `wasmi` already has a public dependency on `parity_wasm` let's just use
it! A `clone` is much faster than a serialize + parse, reducing a `wasm-bindgen`
invocation on my machine from 0.2s to 0.18s.
Currently the `wasm-gc-api` crate doesn't expose `parity_wasm::Module` as a
public dependency which means that whenever we want to run a GC (which is twice
per `wasm-bindgen` invocation) we have to serialize and reparse the module a
lot! The `wasm-bindgen` has to serialize, `wasm-gc` then parses, `wasm-gc` then
serializes, and `wasm-bindgen` then parses.
This commit sidesteps all of these operations by ensuring that we always use the
same `parity_wasm::Module` instance, even when multiple versions of the
`parity_wasm` crate are in use. We'll get a speed boost when they happen to
align (which they always should for `wasm-bindgen`), but it'll work even if they
aren't aligned (by going through serialization).
Concretely on my machine this takes a `wasm-bindgen` invocation from 0.5s to
0.2s, a nice win!
This is a bit of a refinement of the solution from #548 to make sure that these
statics are only present on the `wasm32-*` targets, as otherwise these
descriptors are completely inert on other platforms!
* Add a test harness to directly execute wasm tests
This commits adds a few new crates and infrastructure to enable comands like:
cargo test --target wasm32-unknown-unknown
The intention here is to make it as low-friction as possible to write wasm tests
and also have them execute in a reasonable amount of time. Eventually this is
also hopefully enough support to do things like headless testing!
For now though this is defintely MVP status rather than fully fleshed out.
There's some more information at `crates/test/README.md` about how it works and
how to use it, but for now this is mainly intended to play around with locally
in this repository for our own tests.
* Port a numbe of `js-sys` tests to the new test framework
This commit ports a number of existing tests for the `js-sys` crate over to the
new test framework created in the previous commit, showing off how they can be
executed as well as drastictlly simplifying the tests themselves! This is
intended to be a proof of concept for now which we can refine over time. This
should also show off that it's possible to incrementally move over to the new
test framework.
* Bump to 0.2.12
* Update all version numbers and deps
* Update all listed authors to `["The wasm-bindgen Developers"]`
* Update `repository` links to specific paths for each crate
* Update `homepage` links to the online book
* Update all links away from `alexcrichton/wasm-bindgen`
* Add `#[doc]` directives for HTML URLs
* Update more version requirements
* Fill out CHANGELOG
* Shard the `convert.rs` module into sub-modules
Hopefully this'll make the organization a little nicer over time!
* Start adding support for optional types
This commit starts adding support for optional types to wasm-bindgen as
arguments/return values to functions. The strategy here is to add two new
traits, `OptionIntoWasmAbi` and `OptionFromWasmAbi`. These two traits are used
as a blanket impl to implement `IntoWasmAbi` and `FromWasmAbi` for `Option<T>`.
Some consequences of this design:
* It should be possible to ensure `Option<SomeForeignType>` implements to/from
wasm traits. This is because the option-based traits can be implemented for
foreign types.
* A specialized implementation is possible for all types, so there's no need for
`Option<T>` to introduce unnecessary overhead.
* Two new traits is a bit unforutnate but I can't currently think of an
alternative design that works for the above two constraints, although it
doesn't mean one doesn't exist!
* The error messages for "can't use this type here" is actually halfway decent
because it says these new traits need to be implemented, which provides a good
place to document and talk about what's going on here!
* Nested references like `Option<&T>` can't implement `FromWasmAbi`. This means
that you can't define a function in Rust which takes `Option<&str>`. It may be
possible to do this one day but it'll likely require more trait trickery than
I'm capable of right now.
* Add support for optional slices
This commit adds support for optional slice types, things like strings and
arrays. The null representation of these has a pointer value of 0, which should
never happen in normal Rust. Otherwise the various plumbing is done throughout
the tooling to enable these types in all locations.
* Fix `takeObject` on global sentinels
These don't have a reference count as they're always expected to work, so avoid
actually dropping a reference on them.
* Remove some no longer needed bindings
* Add support for optional anyref types
This commit adds support for optional imported class types. Each type imported
with `#[wasm_bindgen]` automatically implements the relevant traits and now
supports `Option<Foo>` in various argument/return positions.
* Fix building without the `std` feature
* Actually fix the build...
* Add support for optional types to WebIDL
Closes#502
This commit adds a hack to the `wasm-bindgen` CLI tool to work around #483 which
is present on nightly Rust with the recent LLVM upgrade. Hopefully this'll carry
us forward until the [upstream bug][1] is fixed.
Closes#483
[1]: https://bugs.llvm.org/show_bug.cgi?id=38184
The changes on master Rust insert debug sections now (yay!) but this means that
wasm binaries by default pick up debug sections from the standard library, so
let's remove them by default in wasm-bindgen unless `--debug` is passed
* Create a new `web-sys` crate
This will eventually contain all the WebIDL-generated bindings to Web APIs.
* ci: Test the new `web-sys` crate in CI
* web-sys: Add a small README
* web-sys: Vendor all the WebIDL files from mozilla-central
* backend: Add a pass to remove AST items that use undefined imports
This is necessary for the WebIDL frontend, which can't translate many WebIDL
constructs into equivalent wasm-bindgen AST things yet. It lets us make
incremental progress: we can generate bindings to methods we can support right
now even though there might be methods on the same interface that we can't
support yet.
* webidl: Add a bunch of missing semicolons
* webidl: Make parsing private
It was only `pub` so that we could test it, but we ended up moving towards
integration tests rather than unit tests that assert particular ASTs are parsed
from WebIDL files.
* webidl: Remove uses of undefined import types
* test-project-builder: Build projects in "very verbose" mode
This helps for debugging failing WebIDL-related tests.
* test-project-builder: Add more profiling timers
* test-project-builder: Detect when webpack-dev-server fails
Instead of going into an infinite loop, detect when webpack-dev-server fails to
start up and early exit the test.
* webidl: Specify version for dev-dependency on wasm-bindgen-backend
Instead of only a relative path.
* guide: Add section about contributing to `web-sys`
* WIP enable Event.webidl
Still need to fix and finish the test.
* Update expected webidl output
* Start out a test's status as incomplete
That way if we don't fill it in the error message doesn't look quite so bizarre
* Fix onerror function in headless mode
Otherwise we don't see any output!
* Fix package.json/node_modules handling in project generation
Make sure these are looked up in the git project root rather than the crate root
* Avoid logging body text
This was meant for debugging and is otherwise pretty noisy
* Fix a relative path
* More expected test fixes
* Fix a typo
* test-project-builder: Allow asynchronous tests
* webidl: Convert [Unforgeable] attributes into `#[wasm_bindgen(structural)]`
Fixes#432
* test-project-builder: Print generated WebIDL bindings for debugging purposes
Helps debug bad WebIDL bindings generation inside tests.
* When we can't find a descriptor, say which one can't be found
This helps when debugging things that need to become structural.
* web-sys: Test bindings for Event
* ci: Use `--manifest-path dir` instead of `cd dir && ...`
* web-sys: Just move .webidl files isntead of symlinking to enable them
* tests: Polyfill Array.prototype.values for older browsers in CI
* test-project-builder: Don't panic on poisoned headless test mutex
We only use it to serialize headless tests so that we don't try to bind the port
concurrently. Its OK to run another headless test if an earlier one panicked.
* JsValue: Add {is,as}_{object,function} methods
Allows dynamically casting values to `js::Object` and `js::Function`.
* tidy: Fix whitespace and missing semicolons
* Allow for dynamic feature detection of methods
If we create bindings to a method that doesn't exist in this implementation,
then it shouldn't fail until if/when we actually try and invoke that missing
method.
* tests: Do feature detection in Array.prototype.values test
* Add JsValue::{is_string, as_js_string} methods
And document all the cast/convert/check methods for js value.
* eslint: allow backtick string literals
* Only generate a fallback import function for non-structural imports
