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@stylistic/js/

no-multi-spaces

Multiple spaces in a row that are not used for indentation are typically mistakes. For example:

js

if(foo  === "bar") {}

It's hard to tell, but there are two spaces between foo and ===. Multiple spaces such as this are generally frowned upon in favor of single spaces:

js

if(foo === "bar") {}

Rule Details

This rule aims to disallow multiple whitespace around logical expressions, conditional expressions, declarations, array elements, object properties, sequences and function parameters.

Examples of incorrect code for this rule:

js
/*eslint @stylistic/js/no-multi-spaces: "error"*/

var a =
1;
if(foo
=== "bar") {}
a <<
b
var arr = [1,
2];
a ?
b: c
incorrect

Examples of correct code for this rule:

js
/*eslint @stylistic/js/no-multi-spaces: "error"*/

var a = 1;

if(foo === "bar") {}

a << b

var arr = [1, 2];

a ? b: c
correct

Options

This rule's configuration consists of an object with the following properties:

  • "ignoreEOLComments": true (defaults to false) ignores multiple spaces before comments that occur at the end of lines
  • "exceptions": { "Property": true, "ImportAttribute": true } ("Property" and "ImportAttribute" are the nodes specified by default) specifies nodes to ignore
  • "includeTabs": false (defaults to true) consider multiple tabs or spaces mixed with tabs as multiple spaces

ignoreEOLComments

Examples of incorrect code for this rule with the { "ignoreEOLComments": false } (default) option:

js
/*eslint @stylistic/js/no-multi-spaces: ["error", { ignoreEOLComments: false }]*/

var x = 5;
// comment
var x = 5;
/* multiline
* comment */
incorrect

Examples of correct code for this rule with the { "ignoreEOLComments": false } (default) option:

js
/*eslint @stylistic/js/no-multi-spaces: ["error", { ignoreEOLComments: false }]*/

var x = 5; // comment
var x = 5; /* multiline
 * comment
 */
correct

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

js
/*eslint @stylistic/js/no-multi-spaces: ["error", { ignoreEOLComments: true }]*/

var x = 5; // comment
var x = 5;      // comment
var x = 5; /* multiline
 * comment
 */
var x = 5;      /* multiline
 * comment
 */
correct

exceptions

To avoid contradictions with other rules that require multiple spaces, this rule has an exceptions option to ignore certain nodes.

This option is an object that expects property names to be AST node types as defined by ESTree. The easiest way to determine the node types for exceptions is to use AST Explorer with the espree parser.

The Property and ImportAttribute node types are ignored by default, because for the key-spacing rule some alignment options require multiple spaces in properties of object literals and import attributes.

Examples of correct code for the default "exceptions": { "Property": true, "ImportAttribute": true } option:

js
/*eslint @stylistic/js/no-multi-spaces: "error"*/
/*eslint key-spacing: ["error", { align: "value" }]*/

var obj = {
    first:  "first",
    second: "second"
};
correct

Examples of incorrect code for the "exceptions": { "Property": false } option:

js
/*eslint @stylistic/js/no-multi-spaces: ["error", { exceptions: { "Property": false } }]*/
/*eslint key-spacing: ["error", { align: "value" }]*/

var obj = {
    first:
"first",
second: "second" };
incorrect

Examples of correct code for the "exceptions": { "BinaryExpression": true } option:

js
/*eslint @stylistic/js/no-multi-spaces: ["error", { exceptions: { "BinaryExpression": true } }]*/

var a = 1  *  2;
correct

Examples of correct code for the "exceptions": { "VariableDeclarator": true } option:

js
/*eslint @stylistic/js/no-multi-spaces: ["error", { exceptions: { "VariableDeclarator": true } }]*/

var someVar      = 'foo';
var someOtherVar = 'barBaz';
correct

Examples of correct code for the "exceptions": { "ImportDeclaration": true } option:

js
/*eslint @stylistic/js/no-multi-spaces: ["error", { exceptions: { "ImportDeclaration": true } }]*/

import mod          from 'mod';
import someOtherMod from 'some-other-mod';
correct

includeTabs

Consider multiple tabs (\t) or spaces mixed with tabs as multiple spaces for this rule. This option defaults to true.

Example of incorrect code for this rule with the { "includeTabs": true } option:

js
/*eslint @stylistic/js/no-multi-spaces: ["error", { "includeTabs": true }]*/

var a =
1 +
2;
incorrect

When Not To Use It

If you don't want to check and disallow multiple spaces, then you should turn this rule off.

Released under the MIT License.