Blacklist certain identifiers to prevent them being used (id-blacklist)

"There are only two hard things in Computer Science: cache invalidation and naming things." — Phil Karlton

Bad names can lead to hard to decipher code. Using generic names, such as data don't infer much about the code and the values it receives. This rule allows you to configure a blacklist of bad identifier names, that you don't want to see in your code.

Rule Details

This rule compares assignments and function definitions to a provided list of identifier names. If the identifier is present in the list, it will return an error.

This rule will catch blacklisted identifiers that are:

It will not catch blacklisted identifiers that are:

Options

This rule needs a a set of identifier names to blacklist, like so:

{
    "rules": {
        "id-blacklist": [2, "data", "err", "e", "cb", "callback"]
    }
}

For the rule in this example, the following patterns are considered problems:

/*eslint id-blacklist: [2, "data", "err", "e", "cb", "callback"] */

var data = {...};                  /*error Identifier 'data' is blacklisted*/

function callback() {              /*error Identifier 'callback' is blacklisted*/
    // ...
}

element.callback = function() {    /*error Identifier 'callback' is blacklisted*/
    // ...
};

var itemSet = {
    data: [...]                    /*error Identifier 'data' is blacklisted*/
};

The following patterns are not considered problems:

/*eslint id-blacklist: [2, "data", "err", "e", "cb", "callback"] */

var encodingOptions = {...};

function processFileResult() {
    // ...
}

element.successHandler = function() {
    // ...
};

var itemSet = {
    entities: [...]
};

callback()  // all function calls are ignored

foo.callback() // all function calls are ignored

foo.data // all property names that are not assignments are ignored

When Not To Use It

You can turn this rule off if you are happy for identifiers to be named freely.

Version

This rule was introduced in ESLint 2.0.0-beta.2.

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