error: the `self` argument is only allowed for functions in `impl` blocks.

       If the function is already in an `impl` block, did you perhaps forget to add `#[wasm_bindgen]` to the `impl` block?
  --> ui-tests/invalid-self.rs:11:17
   |
11 |     pub fn foo(&self) {}
   |                 ^^^^

error: the `self` argument is not allowed for `extern` functions.

       Did you perhaps mean `this`? For more information on importing JavaScript functions, see:
       https://wasm-bindgen.github.io/wasm-bindgen/examples/import-js.html
  --> ui-tests/invalid-self.rs:20:15
   |
20 |     fn render(self: &MyClass) -> String;
   |               ^^^^
