Fixes babel#7597

Ensure that `Symbol` exists and is a function before using it. We ran into an issue with the usage of `Symbol` breaking on ie11 because it is not supported.
sharmilajesupaul · Oct 31, 2018 · 0ba8392 · 0ba8392
1 parent de80aef
commit 0ba8392
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Showing 3 changed files with 23 additions and 5 deletions.
diff --git a/packages/babel-helpers/src/helpers.js b/packages/babel-helpers/src/helpers.js
@@ -1539,7 +1539,8 @@ helpers.decorate = helper("7.0.2")`
       value: "Descriptor",
       configurable: true,
     };
-    Object.defineProperty(obj, Symbol.toStringTag, desc);
+
+    if (typeof Symbol === 'function' && Symbol.toStringTag) Object.defineProperty(obj, Symbol.toStringTag, desc);
 
     if (element.kind === "field") obj.initializer = element.initializer;
 
@@ -1653,7 +1654,8 @@ helpers.decorate = helper("7.0.2")`
     };
 
     var desc = { value: "Descriptor", configurable: true };
-    Object.defineProperty(obj, Symbol.toStringTag, desc);
+
+    if (typeof Symbol === 'function' && Symbol.toStringTag) Object.defineProperty(obj, Symbol.toStringTag, desc);
 
     return obj;
   }

diff --git a/packages/babel-runtime/helpers/esm/iterableToArray.js b/packages/babel-runtime/helpers/esm/iterableToArray.js
@@ -1,3 +1,11 @@
 export default function _iterableToArray(iter) {
-  if (Symbol.iterator in Object(iter) || Object.prototype.toString.call(iter) === "[object Arguments]") return Array.from(iter);
-}
+  if (
+    Array.isArray(iter)
+    || typeof iter === 'string'
+    || (typeof Symbol === 'function' && Symbol.iterator in Object(iter))
+    || (iter && 'length' in iter)
+    || (typeof Map !== 'undefined' && iter instanceof Map)
+    || (typeof Set !== 'undefined' && iter instanceof Set)
+    || Object.prototype.toString.call(iter) === "[object Arguments]"
+  ) return Array.from(iter);
+}
diff --git a/packages/babel-runtime/helpers/iterableToArray.js b/packages/babel-runtime/helpers/iterableToArray.js
@@ -1,5 +1,13 @@
 function _iterableToArray(iter) {
-  if (Symbol.iterator in Object(iter) || Object.prototype.toString.call(iter) === "[object Arguments]") return Array.from(iter);
+  if (
+    Array.isArray(iter)
+    || typeof iter === 'string'
+    || (typeof Symbol === 'function' && Symbol.iterator in Object(iter))
+    || (iter && 'length' in iter)
+    || (typeof Map !== 'undefined' && iter instanceof Map)
+    || (typeof Set !== 'undefined' && iter instanceof Set)
+    || Object.prototype.toString.call(iter) === "[object Arguments]"
+  ) return Array.from(iter);
 }
 
 module.exports = _iterableToArray;