v1.12.8

CHANGELOG.md

@@ -1,3 +1,7 @@
+# 1.12.8
+
+ * Temporarily forbid `AssignmentExpression` destructuring outside of `ExpressionStatement`.
+
 # 1.12.7
 
  * Update to latest `acorn-6to5`.

doc/differences.md

@@ -64,7 +64,7 @@ better suited if you'd like a full ES6 environment with polyfills and all.
 | Browser support              | ✓    | ✓       | ✓      |        |                |             |
 | Array comprehension          | ✓    | ✓       |        |        | ✓              |             |
 | Arrow functions              | ✓    | ✓       | ✓      | ✓      | ✓              | ✓           |
-| Async functions              | ✓    |         | ✓      |        |                |             |
+| Async functions              | ✓    | ✓       | ✓      |        |                |             |
 | Classes                      | ✓    | ✓       | ✓      | ✓      | ✓              | ✓           |
 | Computed property names      | ✓    | ✓       | ✓      | ✓      | ✓              |             |
 | Constants                    | ✓    | ✓       |        |        | ✓              |             |

lib/6to5/transformation/transformers/destructuring.js

@@ -146,6 +146,12 @@ exports.ExpressionStatement = function (node, parent, file, scope) {
   return nodes;
 };
 
+exports.AssignmentExpression = function (node, parent, file) {
+  if (parent.type === "ExpressionStatement") return;
+  if (!t.isPattern(node.left)) return;
+  throw file.errorWithNode(node, "AssignmentExpression destructuring outside of a ExpressionStatement is forbidden due to current 6to5 limitations");
+};
+
 exports.VariableDeclaration = function (node, parent, file, scope) {
   if (t.isForInStatement(parent) || t.isForOfStatement(parent)) return;
 

package.json

@@ -1,7 +1,7 @@
 {
   "name": "6to5",
   "description": "Turn ES6 code into readable vanilla ES5 with source maps",
-  "version": "1.12.7",
+  "version": "1.12.8",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
   "homepage": "https://github.com/6to5/6to5",
   "repository": {

test/fixtures/transformation/destructuring/assignment-expression/actual.js

@@ -0,0 +1 @@
+console.log([x] = [123]);

test/fixtures/transformation/destructuring/assignment-expression/options.json

@@ -0,0 +1,3 @@
+{
+  "throws": "AssignmentExpression destructuring outside of a ExpressionStatement is forbidden due to current 6to5 limitations"
+}