fix: triple __proto__ in patterns should not throw

acornjs · Jan 15, 2020 · 15a87cd · 15a87cd
1 parent 4a44b8b
commit 15a87cd
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Showing 2 changed files with 7 additions and 3 deletions.
diff --git a/acorn/src/expression.js b/acorn/src/expression.js
@@ -44,9 +44,11 @@ pp.checkPropClash = function(prop, propHash, refDestructuringErrors) {
   if (this.options.ecmaVersion >= 6) {
     if (name === "__proto__" && kind === "init") {
       if (propHash.proto) {
-        if (refDestructuringErrors && refDestructuringErrors.doubleProto < 0) refDestructuringErrors.doubleProto = key.start
-        // Backwards-compat kludge. Can be removed in version 6.0
-        else this.raiseRecoverable(key.start, "Redefinition of __proto__ property")
+        if (refDestructuringErrors) {
+          if (refDestructuringErrors.doubleProto < 0)
+            refDestructuringErrors.doubleProto = key.start
+          // Backwards-compat kludge. Can be removed in version 6.0
+        } else this.raiseRecoverable(key.start, "Redefinition of __proto__ property")
       }
       propHash.proto = true
     }

diff --git a/test/tests-harmony.js b/test/tests-harmony.js
@@ -16512,3 +16512,5 @@ test("let x = 1; x = 2", {}, {ecmaVersion: 6})
 test("function *f2() { () => yield / 1 }", {}, {ecmaVersion: 6})
 
 test("({ a = 42, b: c.d } = e)", {}, {ecmaVersion: 6})
+
+test("({ __proto__: x, __proto__: y, __proto__: z }) => {}", {}, {ecmaVersion: 6})