Make no-dupe-keys compare tokens (like no-duplicate-case does)

[robatwilliams]

I see this was originally raised as #12070 (closed). Recently #13485 made no-duplicate-case compare tokens. Seems the same arguments would apply to both and it'd make sense for both rules to work the same way?

What rule do you want to change?
no-dupe-keys

Does this change cause the rule to produce more or fewer warnings?
More

How will the change be implemented? (New option, new default behavior, etc.)?
Default behaviour

Please provide some example code that this change will affect:

const foo = {
  [a]: 1,
  [a]: 2
};

What does the rule currently do for this code?
No error

What will the rule do after it's changed?
Error

Are you willing to submit a pull request to implement this change?
I'm afraid not

[anikethsaha]

Thanks for the issue.

As mentioned #12070 already, there may be few cases still being passed by. But checking the identifier behind an option and documenting some of the cases where it would still give false positive makes sense to me as personally I faced some similar issue as well.

[mdjermanovic]

Recently #13485 made no-duplicate-case compare tokens. Seems the same arguments would apply to both and it'd make sense for both rules to work the same way?

I think it isn't quite the same.

no-duplicate-case was already based on comparing expressions. We changed the algorithm, which just slightly changed the behavior.

For no-dupe-keys, this looks like a much bigger change in behavior: from comparing only static values to comparing expressions.

That said, I'd support this feature, but only if it would be implemented behind an option.

[eslint-deprecated]

Unfortunately, it looks like there wasn't enough interest from the team
or community to implement this change. While we wish we'd be able to
accommodate everyone's requests, we do need to prioritize. We've found
that issues failing to reach accepted status after 21 days tend to
never be accepted, and as such, we close those issues.
This doesn't mean the idea isn't interesting or useful, just that it's
not something the team can commit to.

Thanks for contributing to ESLint and we appreciate your understanding.