enforce consistent line breaks inside braces (object-curly-newline)

The --fix option on the command line can automatically fix some of the problems reported by this rule.

A number of style guides require or disallow line breaks inside of object braces and other tokens.

Rule Details

This rule enforces consistent line breaks inside braces of object literals or destructuring assignments.

Options

This rule has either a string option:

Or an object option:

You can specify different options for object literals, destructuring assignments, and named imports and exports:

{
    "object-curly-newline": ["error", {
        "ObjectExpression": "always",
        "ObjectPattern": { "multiline": true },
        "ImportDeclaration": "never",
        "ExportDeclaration": { "multiline": true, "minProperties": 3 }
    }]
}

always

Examples of incorrect code for this rule with the "always" option:

/*eslint object-curly-newline: ["error", "always"]*/
/*eslint-env es6*/

let a = {};
let b = {foo: 1};
let c = {foo: 1, bar: 2};
let d = {foo: 1,
    bar: 2};
let e = {foo() {
    dosomething();
}};

let {} = obj;
let {f} = obj;
let {g, h} = obj;
let {i,
    j} = obj;
let {k = function() {
    dosomething();
}} = obj;

Examples of correct code for this rule with the "always" option:

/*eslint object-curly-newline: ["error", "always"]*/
/*eslint-env es6*/

let a = {
};
let b = {
    foo: 1
};
let c = {
    foo: 1, bar: 2
};
let d = {
    foo: 1,
    bar: 2
};
let e = {
    foo: function() {
        dosomething();
    }
};

let {
} = obj;
let {
    f
} = obj;
let {
    g, h
} = obj;
let {
    i,
    j
} = obj;
let {
    k = function() {
        dosomething();
    }
} = obj;

never

Examples of incorrect code for this rule with the "never" option:

/*eslint object-curly-newline: ["error", "never"]*/
/*eslint-env es6*/

let a = {
};
let b = {
    foo: 1
};
let c = {
    foo: 1, bar: 2
};
let d = {
    foo: 1,
    bar: 2
};
let e = {
    foo: function() {
        dosomething();
    }
};

let {
} = obj;
let {
    f
} = obj;
let {
    g, h
} = obj;
let {
    i,
    j
} = obj;
let {
    k = function() {
        dosomething();
    }
} = obj;

Examples of correct code for this rule with the "never" option:

/*eslint object-curly-newline: ["error", "never"]*/
/*eslint-env es6*/

let a = {};
let b = {foo: 1};
let c = {foo: 1, bar: 2};
let d = {foo: 1,
    bar: 2};
let e = {foo: function() {
    dosomething();
}};

let {} = obj;
let {f} = obj;
let {g, h} = obj;
let {i,
    j} = obj;
let {k = function() {
    dosomething();
}} = obj;

multiline

Examples of incorrect code for this rule with the { "multiline": true } option:

/*eslint object-curly-newline: ["error", { "multiline": true }]*/
/*eslint-env es6*/

let a = {
};
let b = {
    foo: 1
};
let c = {
    foo: 1, bar: 2
};
let d = {foo: 1,
    bar: 2};
let e = {foo: function() {
    dosomething();
}};

let {
} = obj;
let {
    f
} = obj;
let {
    g, h
} = obj;
let {i,
    j} = obj;
let {k = function() {
    dosomething();
}} = obj;

Examples of correct code for this rule with the { "multiline": true } option:

/*eslint object-curly-newline: ["error", { "multiline": true }]*/
/*eslint-env es6*/

let a = {};
let b = {foo: 1};
let c = {foo: 1, bar: 2};
let d = {
    foo: 1,
    bar: 2
};
let e = {
    foo: function() {
        dosomething();
    }
};

let {} = obj;
let {f} = obj;
let {g, h} = obj;
let {
    i,
    j
} = obj;
let {
    k = function() {
        dosomething();
    }
} = obj;

minProperties

Examples of incorrect code for this rule with the { "minProperties": 2 } option:

/*eslint object-curly-newline: ["error", { "minProperties": 2 }]*/
/*eslint-env es6*/

let a = {
};
let b = {
    foo: 1
};
let c = {foo: 1, bar: 2};
let d = {foo: 1,
    bar: 2};
let e = {
    foo: function() {
        dosomething();
    }
};

let {
} = obj;
let {
    f
} = obj;
let {g, h} = obj;
let {i,
    j} = obj;
let {
    k = function() {
        dosomething();
    }
} = obj;

Examples of correct code for this rule with the { "minProperties": 2 } option:

/*eslint object-curly-newline: ["error", { "minProperties": 2 }]*/
/*eslint-env es6*/

let a = {};
let b = {foo: 1};
let c = {
    foo: 1, bar: 2
};
let d = {
    foo: 1,
    bar: 2
};
let e = {foo: function() {
    dosomething();
}};

let {} = obj;
let {f} = obj;
let {
    g, h
} = obj;
let {
    i,
    j
} = obj;
let {k = function() {
    dosomething();
}} = obj;

consistent

Examples of incorrect code for this rule with the default { "consistent": true } option:

/*eslint object-curly-newline: ["error", { "consistent": true }]*/
/*eslint-env es6*/

let a = {foo: 1
};
let b = {
    foo: 1};
let c = {foo: 1, bar: 2
};
let d = {
    foo: 1, bar: 2};
let e = {foo: function() {
    dosomething();
    }
};
let f = {
    foo: function() {
    dosomething();}};

let {g
} = obj;
let {
    h} = obj;
let {i, j
} = obj;
let {k, l
} = obj;
let {
    m, n} = obj;
let {
    o, p} = obj;
let {q = function() {
    dosomething();
    }
} = obj;
let {
    r = function() {
        dosomething();
    }} = obj;

Examples of correct code for this rule with the default { "consistent": true } option:

/*eslint object-curly-newline: ["error", { "consistent": true }]*/
/*eslint-env es6*/


let empty1 = {};
let empty2 = {
};
let a = {foo: 1};
let b = {
    foo: 1
};
let c = {
    foo: 1, bar: 2
};
let d = {
    foo: 1,
    bar: 2
};
let e = {foo: function() {dosomething();}};
let f = {
    foo: function() {
        dosomething();
    }
};

let {} = obj;
let {
} = obj;
let {g} = obj;
let {
    h
} = obj;
let {i, j} = obj;
let {
    k, l
} = obj;
let {m,
    n} = obj;
let {
    o,
    p
} = obj;
let {q = function() {dosomething();}} = obj;
let {
    r = function() {
        dosomething();
    }
} = obj;

ObjectExpression and ObjectPattern

Examples of incorrect code for this rule with the { "ObjectExpression": "always", "ObjectPattern": "never" } options:

/*eslint object-curly-newline: ["error", { "ObjectExpression": "always", "ObjectPattern": "never" }]*/
/*eslint-env es6*/

let a = {};
let b = {foo: 1};
let c = {foo: 1, bar: 2};
let d = {foo: 1,
    bar: 2};
let e = {foo: function() {
    dosomething();
}};

let {
} = obj;
let {
    f
} = obj;
let {
    g, h
} = obj;
let {
    i,
    j
} = obj;
let {
    k = function() {
        dosomething();
    }
} = obj;

Examples of correct code for this rule with the { "ObjectExpression": "always", "ObjectPattern": "never" } options:

/*eslint object-curly-newline: ["error", { "ObjectExpression": "always", "ObjectPattern": "never" }]*/
/*eslint-env es6*/

let a = {
};
let b = {
    foo: 1
};
let c = {
    foo: 1, bar: 2
};
let d = {
    foo: 1,
    bar: 2
};
let e = {
    foo: function() {
        dosomething();
    }
};

let {} = obj;
let {f} = obj;
let {g, h} = obj;
let {i,
    j} = obj;
let {k = function() {
    dosomething();
}} = obj;

ImportDeclaration and ExportDeclaration

Examples of incorrect code for this rule with the { "ImportDeclaration": "always", "ExportDeclaration": "never" } options:

/*eslint object-curly-newline: ["error", { "ImportDeclaration": "always", "ExportDeclaration": "never" }]*/
/*eslint-env es6*/

import {foo, bar} from 'foo-bar';
import {foo as f, bar} from 'foo-bar';
import {foo,
    bar} from 'foo-bar';

export {
   foo,
   bar
};
export {
   foo as f,
   bar
} from 'foo-bar';

Examples of correct code for this rule with the { "ImportDeclaration": "always", "ExportDeclaration": "never" } options:

/*eslint object-curly-newline: ["error", { "ImportDeclaration": "always", "ExportDeclaration": "never" }]*/
/*eslint-env es6*/

import {
    foo,
    bar
} from 'foo-bar';
import {
    foo, bar
} from 'foo-bar';
import {
    foo as f,
    bar
} from 'foo-bar';

export { foo, bar } from 'foo-bar';
export { foo as f, bar } from 'foo-bar';

Compatibility

When Not To Use It

If you don't want to enforce consistent line breaks inside braces, then it's safe to disable this rule.

Version

This rule was introduced in ESLint 2.12.0.

Resources

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