2015-12-21 10:43:59 +01:00

30 lines
903 B
JavaScript

import * as t from "babel-types";
export let visitor = {
Function(path) {
let params: Array = path.get("params");
// If there's a rest param, no need to loop through it. Also, we need to
// hoist one more level to get `declar` at the right spot.
let hoistTweak = t.isRestElement(params[params.length - 1]) ? 1 : 0;
let outputParamsLength = params.length - hoistTweak;
for (let i = 0; i < outputParamsLength; i++) {
let param = params[i];
if (param.isArrayPattern() || param.isObjectPattern()) {
let uid = path.scope.generateUidIdentifier("ref");
let declar = t.variableDeclaration("let", [
t.variableDeclarator(param.node, uid)
]);
declar._blockHoist = outputParamsLength - i;
path.ensureBlock();
path.get("body").unshiftContainer("body", declar);
param.replaceWith(uid);
}
}
}
};