enforce consistent line breaks after opening and before closing 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 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 theconsistent
option is set totrue
-
"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 theminProperties
option. (SeeminProperties
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';
Compatibility
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.
Related Rules
Version
This rule was introduced in ESLint 2.12.0.
Resources
© OpenJS Foundation and other contributors
Licensed under the MIT License.
https://eslint.org/docs/rules/object-curly-newline