fix: early return when instance is not iterable

babel · Sep 5, 2019 · 017b026 · 017b026
1 parent 2e7bea4
commit 017b026
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Showing 2 changed files with 11 additions and 1 deletion.
diff --git a/packages/babel-helpers/src/helpers.js b/packages/babel-helpers/src/helpers.js
@@ -943,7 +943,7 @@ helpers.iterableToArrayLimit = helper("7.0.0-beta.0")`
     // _e = _iteratorError
     // _i = _iterator
     // _s = _step
-
+    if (!Symbol.iterator in Object(arr)) return;
     var _arr = [];
     var _n = true;
     var _d = false;
@@ -969,6 +969,7 @@ helpers.iterableToArrayLimit = helper("7.0.0-beta.0")`
 
 helpers.iterableToArrayLimitLoose = helper("7.0.0-beta.0")`
   export default function _iterableToArrayLimitLoose(arr, i) {
+    if (!Symbol.iterator in Object(arr)) return;
     var _arr = [];
     for (var _iterator = arr[Symbol.iterator](), _step; !(_step = _iterator.next()).done;) {
       _arr.push(_step.value);

diff --git a/...ges/babel-plugin-transform-destructuring/test/fixtures/destructuring/non-iterable/exec.js b/...ges/babel-plugin-transform-destructuring/test/fixtures/destructuring/non-iterable/exec.js
@@ -0,0 +1,9 @@
+expect(
+  () => {
+    var [foo, bar] = undefined;
+  }).toThrow("Invalid attempt to destructure non-iterable instance");
+
+expect(
+  () => {
+    var foo = [ ...undefined ];
+  }).toThrow("Invalid attempt to spread non-iterable instance");