require-atomic-updates complains about unrelated variable references

[dohse]

Tell us about your environment

• ESLint Version: 6.0.1
• Node Version: 10.15.3
• npm Version: 6.4.1

What parser (default, Babel-ESLint, etc.) are you using?

default

Please show your full configuration:

Configuration

---
  extends: eslint:recommended
  parserOptions:
    ecmaVersion: 2017

What did you do? Please include the actual source code causing the issue, as well as the command that you used to run ESLint.

async function f() {}

async function t() {
  for (const x of ['A', 'B', 'C']) {
    await f(x);
  }
  for (const x of ['A', 'B', 'C']) {
    await (() => f(x))();
  }
}

t();

> eslint atomic-updates.js

What did you expect to happen?

I get no error or a useful explanation what is wrong with this code.

What actually happened? Please include the actual, raw output from ESLint.

I am getting this linting error:

…/atomic-updates/atomic-updates.js
  7:3  error  Possible race condition: `const x` might be reassigned based on an outdated value of `const x`  require-atomic-updates

✖ 1 problem (1 error, 0 warnings)

Are you willing to submit a pull request to fix this bug?

I expect it to take me quiet long to understand the logic. Therefore not at this moment.

[hon2a]

I've just encountered a similar one:

try {
  result = await someAsyncCall(/* ... */)
} catch (e) {
  ctx.status = e.statusCode || 500
  ctx.body = e.error
  return
}

I'm getting an error for both of the assignment lines in the catch block:

[error] Possible race condition: `ctx.status` might be reassigned based on an outdated value of `ctx.status`. (require-atomic-updates)
[error] Possible race condition: `ctx.body` might be reassigned based on an outdated value of `ctx.body`. (require-atomic-updates)

[mysticatea]

Thank you for your report.

I confirmed it. Looks like the initializer in for-of syntax was handled as an assignment.

@hon2a Your case looks different to this issue because it doesn't contain for-of syntax. And I couldn't reproduce it: online demo.

[hon2a]

@mysticatea: Sorry, here you go. Should I create a separate issue then?

[mysticatea]

@hon2a Thanks. It looks the same issue as #11899.

[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 accepted issues failing to be implemented after 90 days tend to
never be implemented, 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.

[nicolo-ribaudo]

Another demo case: demo

export let lock = 2;

export async function f() {
  {
    let lock;
    lock;
  }
  await null;
  lock = 3;
}