TypeScript版本： 3.7.2
搜索词： commonjs export for of
代码

// @module: commonjs
// @target: esnext
let foo = '';
export { foo };
for (foo in {}) { }
for (foo of []) {}
for ({foo} of [{foo}]) {}

预期行为：

for...in 和 for...of 应该更新导出绑定。

for (_a in {}) { 
  exports.foo = foo = _a;
}
for (_b of []) {
  exports.foo = foo = _b;
}
for (_c of [{foo}]) {
  exports.foo = foo = _c.foo;
}

实际行为：

绑定未更新

** playground链接：**https://www.typescriptlang.org/play/?target=99&module=1#code/DYUwLgBAZg9jEF4IHJkG4BQIAeAHGATpAN7RwQC+msBEAFLPAJYB2ExFAlO5RjfYwgwoEANoBdbhz6F6xRhSEjR8uBUnsKQA