add `--options` to find unused options

[ljharb]

I'd like to run a command that ensures that for all rules I have defined, I've defined every possible compatible schema option.

For example, for the "indent" rule, http://eslint.org/docs/rules/indent points out that it can have an object option with 12 different options. I'd like a report, for that rule, of any of the 12 I've omitted in my config.

[ta2edchimp]

Uh, that's a nice idea 👍

The rules' meta property exposes all the required information about the schema of a rule:

eslint.linter.getRules().get('indent').meta.schema

[preco21]

Hi, I'm poking around the code to find out if I can contribute on it, but just stuck finding proper way to display such unused options as an output. For example, you have only specified the first argument (off, error, ...) in a rule which can accept bunch of additional and also nested options.

In this case, what would be the best to show on the output? I guess only first level of the options would be sufficient for everyone:

NOTE: The user may need to provide a value to rest of the options to clear the output.

unused options (only first level of full options shown)

indent: [0] -> 'tab' | number, [1] -> {SwitchCase, FooBar, ...} // ['error', 'tab', {SwitchCase, ...}]
padding-line-between-statements: [] -> {blankLine, prev, next} // ['error', {blankLine,prev,next}, ...]

[ljharb]

Just the names of the options and the rule, and the link to the rule docs, would be sufficient for me.

[preco21]

Is there an example of what “names of the options and the rule” would look like?

For example: https://eslint.org/docs/rules/indent

In a rule like “indent”, it may not only accept an object as a options, but also accept primitive values like “tab” or 8 along with other options. What would be the best way to deal with this case? Since a primitive value cannot describe its name unlike a key of an object, I guess showing its value type would be okay.

And there may be nested options where some object can contain another object, what would be the output in this case?

[ljharb]

I’d be interested in the kinds of options unset, but not their potential values unless it’s an enum or a boolean. In the case of indent, the object option keys is what I’m most interested in.