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!
If the setter doesn't start with `set_*` then we currently panic, but
panicking is bad! Instead let's thread through structured errors to make
sure they make their way to the top
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 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
This commit fixes annotations that include both the `constructor` and `catch`
attributes on imported types, ensuring that we infer the right type being
returned after extracting the first type parameter of the `Result`.
Closes#735
This commit implements the `extends` attribute for `#[wasm_bindgen]` to
statically draw the inheritance hierarchy in the generated bindings, generating
appropriate `AsRef`, `AsMut`, and `From` implementations.
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.
* Make ConvertToAst trait fallible
It's got some panics, and we'll be switching those to errors!
* First example of a diagnostic-driven error
Add a diagnostic-driven error `#[wasm_bindgen]` being attached to public
functions, and add some macros to boot to make it easier to generate errors!
* Result-ify `src/parser.rs`
This commit converts all of `src/parser.rs` away from panics to using
`Diagnostic` instead. Along the way this adds a test case per changed `panic!`,
ensuring that we don't regress in these areas!
This commit starts to add infrastructure for targeted diagnostics in the
`#[wasm_bindgen]` attribute, intended eventually at providing much better errors
as they'll be pointing to exactly the code in question rather than always to a
`#[wasm_bindgen]` attribute.
The general changes are are:
* A new `Diagnostic` error type is added to the backend. A `Diagnostic` is
created with a textual error or with a span, and it can also be created from a
list of diagnostics. A `Diagnostic` implements `ToTokens` which emits a bunch
of invocations of `compile_error!` that will cause rustc to later generate
errors.
* Fallible implementations of `ToTokens` have switched to using a new trait,
`TryToTokens`, which returns a `Result` to use `?` with.
* The `MacroParse` trait has changed to returning a `Result` to propagate errors
upwards.
* A new `ui-tests` crate was added which uses `compiletest_rs` to add UI tests.
These UI tests will verify that our output improves over time and does not
regress. This test suite is added to CI as a new builder as well.
* No `Diagnostic` instances are created just yet, everything continues to panic
and return `Ok`, with the one exception of the top-level invocations of
`syn::parse` which now create a `Diagnostic` and pass it along.
This commit does not immediately improve diagnostics but the intention is that
it is laying the groundwork for improving diagnostics over time. It should
ideally be much easier to contribute improved diagnostics after this commit!
cc #601
