Error in Safari when loading without-a-bundler-no-modules example

[j-devel]

Describe the Bug

We see an error in Safari when loading the without-a-bundler-no-modules example.

Steps to Reproduce

1. git clone https://github.com/rustwasm/wasm-bindgen
2. cp -r wasm-bindgen/examples/without-a-bundler-no-modules .
3. cd without-a-bundler-no-modules
4. wasm-pack build --target no-modules
5. Statically serve the without-a-bundler-no-modules directory and visit index.html using Safari.

Actual Behavior

The example doesn't load leaving an error in the developer console:

ReferenceError: Can't find variable: wasm_bindgen

Analysis

By loading generated pkg/without_a_bundler_no_modules.js:

let wasm_bindgen;
...

wasm_bindgen is expected to be globally exported, which works fine in Chrome/Firefox, but not in Safari. In case of Safari, the scoping behavior seems different; the let variable becomes scoped in the <script> block (a relevant case here).

As a workaround, should we update crates/cli-support/src/js/mod.rs so that it generates JS like the following instead?

var wasm_bindgen;
...

[alexcrichton]

Thanks for the report! This is a copy-paste typo where type=module isn't supposed to be there.