Rename and name hiding/conflicts

[JayBazuzi]

Given this input:

function f() {
    const x = 1;
    {
        const y = 2;
        {
            return x;
        }
    }
}

• Rename x to y
• Rename y to x

Both should be rejected as errors.

[JayBazuzi]

I can't tell if either of these are handled correctly right now, but figured I should open an issue to track it anyway.

[devill]

Hah! Interesting! It should be super easy to add a fixture test. Just tell the agent to create a fixture test for this, it will most likely get it the first time :)

[fletchgqc]

Sorry, I didn't notice that @JayBazuzi was already working on this when I created #76.

@devill the contribution guidelines say that one should assign oneself an issue when one starts work. But by default, I don't have permission to do that.

[devill]

@fletchgqc I assigned you! I'll have to update the guideline, because I didn't know that people can't assign themselves by default :)

[JayBazuzi]

Now renaming x->y is correctly detected as an error, but renaming y->x is not. This should be reopened.