Fix: default rest argument array elements as undefined (#14032)

packages/babel-plugin-transform-parameters/src/rest.ts

@@ -242,6 +242,8 @@ export default function convertFunctionRest(path) {
 
   let rest = node.params.pop().argument;
 
+  if (rest.name === "arguments") scope.rename(rest.name);
+
   const argsId = t.identifier("arguments");
 
   if (t.isPattern(rest)) {

packages/babel-plugin-transform-parameters/test/fixtures/parameters/default-arguments/exec.js

@@ -0,0 +1,4 @@
+function func(...arguments) {
+    return arguments;
+}
+expect(func(1, 2, 3)).toStrictEqual([1, 2, 3])

packages/babel-plugin-transform-parameters/test/fixtures/parameters/default-arguments/input.js

@@ -0,0 +1,4 @@
+function func(...arguments) {
+    console.log(arguments); // [1, 2, 3]
+}
+func(1, 2, 3);

packages/babel-plugin-transform-parameters/test/fixtures/parameters/default-arguments/output.js

@@ -0,0 +1,9 @@
+function func() {
+  for (var _len = arguments.length, _arguments = new Array(_len), _key = 0; _key < _len; _key++) {
+    _arguments[_key] = arguments[_key];
+  }
+
+  console.log(_arguments); // [1, 2, 3]
+}
+
+func(1, 2, 3);

packages/babel-plugin-transform-parameters/test/fixtures/parameters/rest-argument-with-other-arguments/exec.js

@@ -0,0 +1,5 @@
+function func(a, b, ...arguments) {
+    return [a, b, arguments];
+}
+
+expect(func('a', 'b', 1, 2, 3)).toStrictEqual(['a', 'b', [1, 2, 3]])

packages/babel-plugin-transform-parameters/test/fixtures/parameters/rest-argument-with-other-arguments/input.js

@@ -0,0 +1,5 @@
+function func(a, b, ...arguments) {
+    return [a, b, arguments];
+}
+
+func('a', 'b', 1, 2, 3)

packages/babel-plugin-transform-parameters/test/fixtures/parameters/rest-argument-with-other-arguments/output.js

@@ -0,0 +1,9 @@
+function func(a, b) {
+  for (var _len = arguments.length, _arguments = new Array(_len > 2 ? _len - 2 : 0), _key = 2; _key < _len; _key++) {
+    _arguments[_key - 2] = arguments[_key];
+  }
+
+  return [a, b, _arguments];
+}
+
+func('a', 'b', 1, 2, 3);