OpenCut/rust/crates/bridge/src/bridge.rs

50 lines
1.2 KiB
Rust

use proc_macro::TokenStream;
use quote::quote;
use syn::{ItemFn, parse_macro_input};
#[proc_macro_attribute]
pub fn export(_attr: TokenStream, item: TokenStream) -> TokenStream {
let function = parse_macro_input!(item as ItemFn);
let js_name = snake_to_camel(&function.sig.ident.to_string());
quote! {
#[cfg_attr(feature = "wasm", ::wasm_bindgen::prelude::wasm_bindgen(js_name = #js_name))]
#function
}
.into()
}
fn snake_to_camel(name: &str) -> String {
let mut camel = String::with_capacity(name.len());
let mut should_uppercase_next = false;
for character in name.chars() {
if character == '_' {
should_uppercase_next = true;
continue;
}
if should_uppercase_next {
camel.push(character.to_ascii_uppercase());
should_uppercase_next = false;
continue;
}
camel.push(character);
}
camel
}
#[cfg(test)]
mod tests {
use super::snake_to_camel;
#[test]
fn converts_snake_case_to_camel_case() {
assert_eq!(snake_to_camel("do_something"), "doSomething");
assert_eq!(snake_to_camel("a_b_c"), "aBC");
assert_eq!(snake_to_camel("already"), "already");
}
}