Commit Graph

7 Commits

Author SHA1 Message Date
Alex Crichton
68c5233f80 First refactor for WebIDL bindings
This commit starts the `wasm-bindgen` CLI tool down the road to being a
true polyfill for WebIDL bindings. This refactor is probably the first
of a few, but is hopefully the largest and most sprawling and everything
will be a bit more targeted from here on out.

The goal of this refactoring is to separate out the massive
`crates/cli-support/src/js/mod.rs` into a number of separate pieces of
functionality. It currently takes care of basically everything
including:

* Binding intrinsics
* Handling anyref transformations
* Generating all JS for imports/exports
* All the logic for how to import and how to name imports
* Execution and management of wasm-bindgen closures

Many of these are separable concerns and most overlap with WebIDL
bindings. The internal refactoring here is intended to make it more
clear who's responsible for what as well as making some existing
operations much more straightforward. At a high-level, the following
changes are done:

1. A `src/webidl.rs` module is introduced. The purpose of this module is
   to take all of the raw wasm-bindgen custom sections from the module
   and transform them into a WebIDL bindings section.

  This module has a placeholder `WebidlCustomSection` which is nowhere
  near the actual custom section but if you squint is in theory very
  similar. It's hoped that this will eventually become the true WebIDL
  custom section, currently being developed in an external crate.

  Currently, however, the WebIDL bindings custom section only covers a
  subset of the functionality we export to wasm-bindgen users. To avoid
  leaving them high and dry this module also contains an auxiliary
  custom section named `WasmBindgenAux`. This custom section isn't
  intended to have a binary format, but is intended to represent a
  theoretical custom section necessary to couple with WebIDL bindings to
  achieve all our desired functionality in `wasm-bindgen`. It'll never
  be standardized, but it'll also never be serialized :)

2. The `src/webidl.rs` module now takes over quite a bit of
   functionality from `src/js/mod.rs`. Namely it handles synthesis of an
   `export_map` and an `import_map` mapping export/import IDs to exactly
   what's expected to be hooked up there. This does not include type
   information (as that's in the bindings section) but rather includes
   things like "this is the method of class A" or "this import is from
   module `foo`" and things like that. These could arguably be subsumed
   by future JS features as well, but that's for another time!

3. All handling of wasm-bindgen "descriptor functions" now happens in a
   dedicated `src/descriptors.rs` module. The output of this module is
   its own custom section (intended to be immediately consumed by the
   WebIDL module) which is in theory what we want to ourselves emit one
   day but rustc isn't capable of doing so right now.

4. Invocations and generations of imports are completely overhauled.
   Using the `import_map` generated in the WebIDL step all imports are
   now handled much more precisely in one location rather than
   haphazardly throughout the module. This means we have precise
   information about each import of the module and we only modify
   exactly what we're looking at. This also vastly simplifies intrinsic
   generation since it's all simply a codegen part of the `rust2js.rs`
   module now.

5. Handling of direct imports which don't have a JS shim generated is
   slightly different from before and is intended to be
   future-compatible with WebIDL bindings in its full glory, but we'll
   need to update it to handle cases for constructors and method calls
   eventually as well.

6. Intrinsic definitions now live in their own file (`src/intrinsic.rs`)
   and have a separated definition for their symbol name and signature.
   The actual implementation of each intrinsic lives in `rust2js.rs`

There's a number of TODO items to finish before this merges. This
includes reimplementing the anyref pass and actually implementing import
maps for other targets. Those will come soon in follow-up commits, but
the entire `tests/wasm/main.rs` suite is currently passing and this
seems like a good checkpoint.
2019-06-05 07:52:14 -07:00
Alex Crichton
15defcfd3a Add a debug assert and more tests 2019-05-13 08:12:32 -07:00
Alex Crichton
3d43d6e5e8 Fix importing and exporting the same name
Run exports through the same identifier generation as imports to ensure
that everything gets a unique identifier and then just make sure all the
appropriate wires are hooked up when dealing with exports and imports.

Closes #1496
2019-05-03 07:15:20 -07:00
Alex Crichton
7ecf4aae87 cargo +nightly fmt --all
Rustfmt all the things!
2018-09-26 08:26:00 -07:00
Nick Fitzgerald
998d37a353 Use the JS name of an imported type for instanceof checks 2018-08-08 14:42:21 -07:00
Alex Crichton
d5b81595ec Remove support for the version attribute
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.
2018-08-06 13:30:28 -05:00
Alex Crichton
4661588171 Move most of the "simple" test to the wasm suite 2018-08-06 09:21:41 -07:00