Alex Crichton b762948456 Implement the local JS snippets RFC
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/6

Closes #1311
2019-03-05 08:00:47 -08:00
..
2019-03-04 09:11:23 -08:00

wasm-bindgen-macro

Implementation of the #[wasm_bindgen] attribute. See the wasm-bindgen documentation for more information about what this macro does.

Testing

Testing of this macro is done through "ui tests" in the ui-tests subdirectory of this crate. Each Rust file in this folder is compiled with the wasm_bindgen crate, and the *.stderr file sitting next to it is the asserted output of the compiler. If the output matches, the test passes, and if the output doesn't match the test fails. Note that it is also considered a failure if a test actually compiles successfully.

To add a test:

  • Create ui-tests/my-awesome-test.rs
  • Write an invalid #[wasm_bindgen] invocation, testing the error you're generating
  • Execute cargo test -p ui-tests, the test will fail
  • From within the ui-tests folder, execute ./update-all-references.sh. This should create a my-awesome-test.stderr file.
  • Inspect my-awesome-test.stderr to make sure it looks ok
  • Rerun cargo test -p ui-tests and your tests should pass!

Testing here is a work in progress, see #601 for more information.