Currently `#[wasm_bindgen]` generates a bunch of references to symbols that
don't actually exist on non-wasm targets, making it more difficult to get a
crate working across multiple platforms. This commit updates the symbol
references to be dummy ones that panic on non-wasm targets to allow simple
testing/benchmarking to work on native targets.
While this isn't a perfect solution for #114 it's probably as good as we can do
for now pending upstream Cargo features, so I'm gonna say that it...
Closes#114
This commit adds a `#[wasm_bindgen(version = "...")]` attribute support. This
information is eventually written into a `__wasm_pack_unstable` section.
Currently this is a strawman for the proposal in ashleygwilliams/wasm-pack#101
Using `proc-macro2`'s `nightly` feature is a good default for most use cases.
However, it causes a build error if used together with crates such as
`cssparser` that also use `proc-macro2` from a build script.
This change adds a default enabled feature `spans` that users can disable if
they need to work around this conflict.
Fixes#160.
The previous codegen wasn't enough to convince LLVM that the function pointer
was a constant value and could be aggressively inlined, so this updates the
`JsStatic` internals slightly to guarantee to LLVM that the function pointer is
constant and no dynamic dispatch is needed after all
Add support for `#[wasm_bindgen(readonly)]` which indicates that an exported
struct field is readonly and attempting to set it in JS will throw an exception.
Closes#151
Automatically infer public struct fields as "JS wants to access this" and
generate appropriate getters/setters for the field. At this time the field is
required to implement `Copy`, but we will probably want to relax that in the
future to at least encompass `JsValue` and maybe other `Clone` values as well.
Closes#121
This commit adds support for both `#![no_std]` in the wasm-bindgen runtime
support (disabled by default with an on-by-default `std` feature). This also
adds support to work and compile in the context of `#![no_std]` crates.
Closes#146
This commit overhauls the conversion traits used for types crossing the Rust/JS
boundary. Previously there were a few ad-hoc traits but now there've been
slightly reduced and decoupled.
Conversion from Rust values to JS values is now exclusively done through
`IntoWasmAbi` with no special treatment for references. Conversion from JS to
Rust is a bit trickier as we want to create references in Rust which have
implications in terms of safety. As a result there are now three traits for
this, `FromWasmAbi`, `RefFromWasmAbi`, and `RefMutFromWasmAbi`. These three
traits are implemented for various types and specially dispatched to depending
on the type of argument in the code generator.
The goal of this commit is to lay the groundwork for using these traits in
closures with straightforward-ish definitions.
This commit adds support for passing `&mut FnMut(..)` to JS via imports. These
closures cannot be invoked recursively in JS (they invalidate themselves while
they're being invoked) and otherwise work the same as `&Fn(..)` closures.
Closes#123
This commit is a complete overhaul of how the `#[wasm_bindgen]` macro
communicates type information to the CLI tool, and it's done in a somewhat...
unconventional fashion.
Today we've got a problem where the generated JS needs to understand the types
of each function exported or imported. This understanding is what enables it to
generate the appropriate JS wrappers and such. We want to, however, be quite
flexible and extensible in types that are supported across the boundary, which
means that internally we rely on the trait system to resolve what's what.
Communicating the type information historically was done by creating a four byte
"descriptor" and using associated type projections to communicate that to the
CLI tool. Unfortunately four bytes isn't a lot of space to cram information like
arguments to a generic function, tuple types, etc. In general this just wasn't
flexible enough and the way custom references were treated was also already a
bit of a hack.
This commit takes a radical step of creating a **descriptor function** for each
function imported/exported. The really crazy part is that the `wasm-bindgen` CLI
tool now embeds a wasm interpreter and executes these functions when the CLI
tool is invoked. By allowing arbitrary functions to get executed it's now *much*
easier to inform `wasm-bindgen` about complicated structures of types. Rest
assured though that all these descriptor functions are automatically unexported
and gc'd away, so this should not have any impact on binary sizes
A new internal trait, `WasmDescribe`, is added to represent a description of all
types, sort of like a serialization of the structure of a type that
`wasm-bindgen` can understand. This works by calling a special exported function
with a `u32` value a bunch of times. This means that when we run a descriptor we
effectively get a `Vec<u32>` in the `wasm-bindgen` CLI tool. This list of
integers can then be parsed into a rich `enum` for the JS generation to work
with.
This commit currently only retains feature parity with the previous
implementation. I hope to soon solve issues like #123, #104, and #111 with this
support.
This commit starts wasm-bindgen down the path of supporting closures. We
discussed this at the recent Rust All-Hands but I ended up needing to pretty
significantly scale back the ambitions of what closures are supported. This
commit is just the initial support and provides only a small amount of support
but will hopefully provide a good basis for future implementations.
Specifically this commit adds support for passing `&Fn(...)` to an *imported
function*, but nothing elese. The `&Fn` type can have any lifetime and the JS
object is invalidated as soon as the import returns. The arguments and return
value of `Fn` must currently implement the `WasmAbi` trait, aka they can't
require any conversions like strings/types/etc.
I'd like to soon expand this to `&mut FnMut` as well as `'static` closures that
can be passed around for a long time in JS, but for now I'm putting that off
until later. I'm not currently sure how to implement richer argument types, but
hopefully that can be figured out at some point!
This commit starts wasm-bindgen down a path of removing the special
casing it currently has around vectors, slices, and strings. This has
long been a thorn in wasm-bindgen's side as it doesn't handle other
kinds of vectors and otherwise is very inflexible with future additions.
Additionally it leads to a lot of duplicated-ish code throughout various
portions of codegen.
The fundamental reason for this was that two arguments were required to
be passed back to wasm, and I couldn't figure out a way to shove both
those arguments into a function argument. The new strategy here is that
there is one global stack well known to both JS and Rust which arguments
*may* also be transferred between.
By default all ABI arguments pass as literal function arguments, but if
two or more arguments need to be passed then the extra ones are all
passed through this global stack. The stack is effectively temporary
scratch space when crossing the JS/Rust boundary (both ways). No long
term storage is intended here.
The `simple` test is passing as a result of this commit, using strings
internally. The `Vector` type in the AST has been removed (yay!) and the
bulk of the implementation of slices and vectors now resides in the
`wasm-bindgen` crate itself, defining how to pass all these arguments
around. The JS generator, however, still needs to know about all the
sorts of vectors so it can generate appropriate code for JS.
Future commits will continue cleanup and get the rest of the tests
working.
