Prettier lint error isn't fixable

Prettier 1.14.3 Playground link

--parser babylon
--single-quote
--trailing-comma es5

Input:

function set(key, value) {
  // DEV NOTE: We use assign here to create a new object so that Ember can
  // register and rollback the changes to availableHours
  const time = Object.assign({}, this.get('time'));
  const selectedPeriod = this.get('selectedPeriod');
  time.hour = (Number(value) % 12) + (selectedPeriod == 'PM' ? 12 : 0);
  this.set('time', time);
  return value;
}

Output:

function set(key, value) {
  // DEV NOTE: We use assign here to create a new object so that Ember can
  // register and rollback the changes to availableHours
  const time = Object.assign({}, this.get('time'));
  const selectedPeriod = this.get('selectedPeriod');
  time.hour = (Number(value) % 12) + (selectedPeriod == 'PM' ? 12 : 0);
  this.set('time', time);
  return value;
}

Expected behavior:

I’ve been running into a pretty frustrating issue where I keep getting a Prettier error, running the autoformatter doesn’t fit it, and then when I fix it manually, I get another error that the original formatting is correct.

Here’s the error:

30:19  error  Replace `(Number(value)·%·12)` with `Number(value)·%·12`  prettier/prettier
69:19  error  Replace `(time.hour·%·12)` with `time.hour·%·12`          prettier/prettier

But when I fix it manually, it shows this error:

30:19  error  Replace `Number(value)·%·12` with `(Number(value)·%·12)`  prettier/prettier
69:19  error  Replace `time.hour·%·12` with `(time.hour·%·12)`          prettier/prettier

And the autoformatter doesn’t notice it at all.

Any thoughts on what I can do? I’m not sure if this issue is in Prettier’s domain or if it’s an issue with the ESLint plugin.

[lydell]

Ok, thanks!

What you need to do now is to reduce your config. Keep removing stuff until the error goes away, or you’re left with the minimal setup to reproduce the problem. Then post all of the files and steps to reproduce here. The easiest way is to make a new repo and put everything there. Let me know if you need any help with any of that!

[jackiehluo]

The “autoformatter” just refers to:

prettier --write --single-quote --trailing-comma es5 'addon/**/*.js' 'app/**/*.js' 'config/**/*.js' 'tests/**/*.js'

I’m using Ember, so ESLint gets run as a part of ember test, and ESLint is both disagreeing with Prettier and disagreeing with itself. Running the above Prettier command never shows any formatting issues. Running ESLint shows a Prettier error, and then if I fix the error, it says that my original code was correct and throws a new lint error that contradicts the prior one.

We’re already using eslint-config-prettier!