Awesome

eslint-plugin-json-files

ESLint JSON processor and rules

You'll first need to install ESLint:

$ npm i eslint --save-dev

Next, install eslint-plugin-json-files:

$ npm install eslint-plugin-json-files --save-dev

Note: If you installed ESLint globally (using the -g flag) then you must also install eslint-plugin-json-files globally.

Add json-files to the plugins section of your .eslintrc configuration file. You can omit the eslint-plugin- prefix:

{
    "plugins": [
        "json-files"
    ]
}

Then configure the rules you want to use under the rules section.

{
    "rules": {
        "json-files/rule-name": "error"
    }
}

Don't forget to use the extension option.

eslint . --ext js,json

Rule ID	Description
json-files/ensure-repository-directory	ensure repository/directory in package.json
json-files/ensure-volta-extends	ensure volta-extends in package.json
json-files/ensure-workspaces	ensure workspace globs in package.json resolve to directories
json-files/eol-last	require or disallow newline at the end of package.json
json-files/no-branch-in-dependencies	prevent branches in package.json dependencies
json-files/require-engines	require the engines field in package.json
json-files/require-license	require a license in package.json
json-files/require-unique-dependency-names	prevent duplicate packages in dependencies and devDependencies
json-files/restrict-ranges	restrict the dependency ranges in package.json
json-files/sort-package-json	enforce package.json sorting
json-files/validate-schema	require a valid JSON Schema

I wouldn't mind getting this merged into eslint-plugin-node or eslint-plugin-json.