Check scope before wrapping

Author: zodern

lib/assignment-visitor.js

@@ -79,10 +79,15 @@ function assignmentHelper(visitor, path, childName) {
   const child = path.getValue()[childName];
   const assignedNames = utils.getNamesFromPattern(child);
   const nameCount = assignedNames.length;
+  const scope = path.getScope();
 
   // Wrap assignments to exported identifiers with `module.runSetters`.
   for (let i = 0; i < nameCount; ++i) {
-    if (visitor.exportedLocalNames[assignedNames[i]] === true) {
+    let name = assignedNames[i];
+    if (
+      visitor.exportedLocalNames[name] === true &&
+      (!scope || scope.find_owner(name).parent === null)
+    ) {
       wrap(visitor, path);
       break;
     }

lib/fast-path.js

@@ -5,6 +5,7 @@
 
 const assert = require("assert");
 const utils = require("./utils.js");
+const periscopic = require('periscopic');
 const brandKey = "reify-fast-path";
 const brand = typeof Symbol === "function"
   ? Symbol.for(brandKey)
@@ -15,6 +16,7 @@ class FastPath {
     assert.notStrictEqual(ast, null);
     assert.strictEqual(typeof ast, "object");
     this.stack = [ast];
+    this._scope = null;
   }
 
   static isInstance(value) {
@@ -102,6 +104,21 @@ class FastPath {
     return getStackAt(this, 1);
   }
 
+  getScope() {
+    if (!this._scope) {
+      this._scope = periscopic.analyze(this.stack[0]);
+    }
+
+    let node;
+    let pos = 0;
+    while (node = getNodeAt(this, pos++)) {
+      let scope = this._scope.map.get(node);
+      if (scope) {
+        return scope;
+      }
+    }
+  }
+
   replace(newValue) {
     const s = this.stack;
     const len = s.length;