Variable Scope Problem

[YiWen-y]

Version

0.10.0

Test case

var foo = function() {
    var x = 3;
    if (x > 0) {
        let x = 7;
        print(x);
    }
    print(x);
};
foo();

Execution steps

.jsvu/hermes Testcase.js

Output

7 7

Expected behavior

7 3

Description

The correct output of the test case should be 7 3 while hermes outputs 7 7. I think hermes fails to deal with the scope of the global and local variable x, where hermes may treat the local variable x at line 4 as the global variable, leading to output 7 at line 7.

[neildhar]

Hi @YiWen-y, Hermes does not support block scoping, and we instead rely on Babel transforms to lower cases like these into something that can run in Hermes. Please see #575 for more details.