Versions

object-curly-newline

Enforce consistent line breaks after opening and before closing braces

🛠 Fixable

Some problems reported by this rule are automatically fixable by the --fix command line option

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

Rule Details

This rule requires or disallows a line break between { and its following token, and between } and its preceding token of object literals or destructuring assignments.

Options

This rule has either a string option:

  • "always" requires line breaks after opening and before closing braces
  • "never" disallows line breaks after opening and before closing braces

Or an object option:

  • "multiline": true requires line breaks if there are line breaks inside properties or between properties. Otherwise, it disallows line breaks.
  • "minProperties" requires line breaks if the number of properties is at least the given integer. By default, an error will also be reported if an object contains linebreaks and has fewer properties than the given integer. However, the second behavior is disabled if the consistent option is set to true
  • "consistent": true (default) requires that either both curly braces, or neither, directly enclose newlines. Note that enabling this option will also change the behavior of the minProperties option. (See minProperties above for more information)

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 }
}]
}
  • "ObjectExpression" configuration for object literals
  • "ObjectPattern" configuration for object patterns of destructuring assignments
  • "ImportDeclaration" configuration for named imports
  • "ExportDeclaration" configuration for named exports

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';

When Not To Use It

If you don’t want to enforce consistent line breaks after opening and before closing braces, then it’s safe to disable this rule.

Compatibility

Version

This rule was introduced in ESLint v2.12.0.

Resources