45 lines
1.2 KiB
JavaScript

import remapAsyncToGenerator from "@babel/helper-remap-async-to-generator";
import syntaxAsyncGenerators from "@babel/plugin-syntax-async-generators";
export default function({ types: t }) {
const yieldStarVisitor = {
Function(path) {
path.skip();
},
YieldExpression({ node }, state) {
if (!node.delegate) return;
const callee = state.addHelper("asyncGeneratorDelegate");
node.argument = t.callExpression(callee, [
t.callExpression(state.addHelper("asyncIterator"), [node.argument]),
t.memberExpression(
state.addHelper("asyncGenerator"),
t.identifier("await"),
),
]);
},
};
return {
inherits: syntaxAsyncGenerators,
visitor: {
Function(path, state) {
if (!path.node.async || !path.node.generator) return;
path.traverse(yieldStarVisitor, state);
remapAsyncToGenerator(path, state.file, {
wrapAsync: t.memberExpression(
state.addHelper("asyncGenerator"),
t.identifier("wrap"),
),
wrapAwait: t.memberExpression(
state.addHelper("asyncGenerator"),
t.identifier("await"),
),
});
},
},
};
}