enforce consistent indentation (indent-legacy)

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

This rule was deprecated in ESLint v4.0.0.

ESLint 4.0.0 introduced a rewrite of the indent rule, which now reports more errors than it did in previous versions. To ease the process of migrating to 4.0.0, the indent-legacy rule was introduced as a snapshot of the indent rule from ESLint 3.x. If your build is failing after the upgrade to 4.0.0, you can disable indent and enable indent-legacy as a quick fix. Eventually, you should switch back to the indent rule to get bugfixes and improvements in future versions.


There are several common guidelines which require specific indentation of nested blocks and statements, like:

function hello(indentSize, type) {
    if (indentSize === 4 && type !== 'tab') {
        console.log('Each next indentation will increase on 4 spaces');
    }
}

These are the most common scenarios recommended in different style guides:

Rule Details

This rule enforces a consistent indentation style. The default style is 4 spaces.

Options

This rule has a mixed option:

For example, for 2-space indentation:

{
    "indent": ["error", 2]
}

Or for tabbed indentation:

{
    "indent": ["error", "tab"]
}

Examples of incorrect code for this rule with the default options:

/*eslint indent: "error"*/

if (a) {
  b=c;
  function foo(d) {
    e=f;
  }
}

Examples of correct code for this rule with the default options:

/*eslint indent: "error"*/

if (a) {
    b=c;
    function foo(d) {
        e=f;
    }
}

This rule has an object option:

Level of indentation denotes the multiple of the indent specified. Example:

tab

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

/*eslint indent: ["error", "tab"]*/

if (a) {
     b=c;
function foo(d) {
           e=f;
 }
}

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

/*eslint indent: ["error", "tab"]*/

if (a) {
/*tab*/b=c;
/*tab*/function foo(d) {
/*tab*//*tab*/e=f;
/*tab*/}
}

SwitchCase

Examples of incorrect code for this rule with the 2, { "SwitchCase": 1 } options:

/*eslint indent: ["error", 2, { "SwitchCase": 1 }]*/

switch(a){
case "a":
    break;
case "b":
    break;
}

Examples of correct code for this rule with the 2, { "SwitchCase": 1 } option:

/*eslint indent: ["error", 2, { "SwitchCase": 1 }]*/

switch(a){
  case "a":
    break;
  case "b":
    break;
}

VariableDeclarator

Examples of incorrect code for this rule with the 2, { "VariableDeclarator": 1 } options:

/*eslint indent: ["error", 2, { "VariableDeclarator": 1 }]*/
/*eslint-env es6*/

var a,
    b,
    c;
let a,
    b,
    c;
const a = 1,
    b = 2,
    c = 3;

Examples of correct code for this rule with the 2, { "VariableDeclarator": 1 } options:

/*eslint indent: ["error", 2, { "VariableDeclarator": 1 }]*/
/*eslint-env es6*/

var a,
  b,
  c;
let a,
  b,
  c;
const a = 1,
  b = 2,
  c = 3;

Examples of correct code for this rule with the 2, { "VariableDeclarator": 2 } options:

/*eslint indent: ["error", 2, { "VariableDeclarator": 2 }]*/
/*eslint-env es6*/

var a,
    b,
    c;
let a,
    b,
    c;
const a = 1,
    b = 2,
    c = 3;

Examples of correct code for this rule with the 2, { "VariableDeclarator": { "var": 2, "let": 2, "const": 3 } } options:

/*eslint indent: ["error", 2, { "VariableDeclarator": { "var": 2, "let": 2, "const": 3 } }]*/
/*eslint-env es6*/

var a,
    b,
    c;
let a,
    b,
    c;
const a = 1,
      b = 2,
      c = 3;

outerIIFEBody

Examples of incorrect code for this rule with the options 2, { "outerIIFEBody": 0 }:

/*eslint indent: ["error", 2, { "outerIIFEBody": 0 }]*/

(function() {

  function foo(x) {
    return x + 1;
  }

})();


if(y) {
console.log('foo');
}

Examples of correct code for this rule with the options 2, {"outerIIFEBody": 0}:

/*eslint indent: ["error", 2, { "outerIIFEBody": 0 }]*/

(function() {

function foo(x) {
  return x + 1;
}

})();


if(y) {
   console.log('foo');
}

MemberExpression

Examples of incorrect code for this rule with the 2, { "MemberExpression": 1 } options:

/*eslint indent: ["error", 2, { "MemberExpression": 1 }]*/

foo
.bar
.baz()

Examples of correct code for this rule with the 2, { "MemberExpression": 1 } option:

/*eslint indent: ["error", 2, { "MemberExpression": 1 }]*/

foo
  .bar
  .baz();

// Any indentation is permitted in variable declarations and assignments.
var bip = aardvark.badger
                  .coyote;

FunctionDeclaration

Examples of incorrect code for this rule with the 2, { "FunctionDeclaration": {"body": 1, "parameters": 2} } option:

/*eslint indent: ["error", 2, { "FunctionDeclaration": {"body": 1, "parameters": 2} }]*/

function foo(bar,
  baz,
  qux) {
    qux();
}

Examples of correct code for this rule with the 2, { "FunctionDeclaration": {"body": 1, "parameters": 2} } option:

/*eslint indent: ["error", 2, { "FunctionDeclaration": {"body": 1, "parameters": 2} }]*/

function foo(bar,
    baz,
    qux) {
  qux();
}

Examples of incorrect code for this rule with the 2, { "FunctionDeclaration": {"parameters": "first"} } option:

/*eslint indent: ["error", 2, {"FunctionDeclaration": {"parameters": "first"}}]*/

function foo(bar, baz,
  qux, boop) {
  qux();
}

Examples of correct code for this rule with the 2, { "FunctionDeclaration": {"parameters": "first"} } option:

/*eslint indent: ["error", 2, {"FunctionDeclaration": {"parameters": "first"}}]*/

function foo(bar, baz,
             qux, boop) {
  qux();
}

FunctionExpression

Examples of incorrect code for this rule with the 2, { "FunctionExpression": {"body": 1, "parameters": 2} } option:

/*eslint indent: ["error", 2, { "FunctionExpression": {"body": 1, "parameters": 2} }]*/

var foo = function(bar,
  baz,
  qux) {
    qux();
}

Examples of correct code for this rule with the 2, { "FunctionExpression": {"body": 1, "parameters": 2} } option:

/*eslint indent: ["error", 2, { "FunctionExpression": {"body": 1, "parameters": 2} }]*/

var foo = function(bar,
    baz,
    qux) {
  qux();
}

Examples of incorrect code for this rule with the 2, { "FunctionExpression": {"parameters": "first"} } option:

/*eslint indent: ["error", 2, {"FunctionExpression": {"parameters": "first"}}]*/

var foo = function(bar, baz,
  qux, boop) {
  qux();
}

Examples of correct code for this rule with the 2, { "FunctionExpression": {"parameters": "first"} } option:

/*eslint indent: ["error", 2, {"FunctionExpression": {"parameters": "first"}}]*/

var foo = function(bar, baz,
                   qux, boop) {
  qux();
}

CallExpression

Examples of incorrect code for this rule with the 2, { "CallExpression": {"arguments": 1} } option:

/*eslint indent: ["error", 2, { "CallExpression": {"arguments": 1} }]*/

foo(bar,
    baz,
      qux
);

Examples of correct code for this rule with the 2, { "CallExpression": {"arguments": 1} } option:

/*eslint indent: ["error", 2, { "CallExpression": {"arguments": 1} }]*/

foo(bar,
  baz,
  qux
);

Examples of incorrect code for this rule with the 2, { "CallExpression": {"arguments": "first"} } option:

/*eslint indent: ["error", 2, {"CallExpression": {"arguments": "first"}}]*/

foo(bar, baz,
  baz, boop, beep);

Examples of correct code for this rule with the 2, { "CallExpression": {"arguments": "first"} } option:

/*eslint indent: ["error", 2, {"CallExpression": {"arguments": "first"}}]*/

foo(bar, baz,
    baz, boop, beep);

ArrayExpression

Examples of incorrect code for this rule with the 2, { "ArrayExpression": 1 } option:

/*eslint indent: ["error", 2, { "ArrayExpression": 1 }]*/

var foo = [
    bar,
baz,
      qux
];

Examples of correct code for this rule with the 2, { "ArrayExpression": 1 } option:

/*eslint indent: ["error", 2, { "ArrayExpression": 1 }]*/

var foo = [
  bar,
  baz,
  qux
];

Examples of incorrect code for this rule with the 2, { "ArrayExpression": "first" } option:

/*eslint indent: ["error", 2, {"ArrayExpression": "first"}]*/

var foo = [bar,
  baz,
  qux
];

Examples of correct code for this rule with the 2, { "ArrayExpression": "first" } option:

/*eslint indent: ["error", 2, {"ArrayExpression": "first"}]*/

var foo = [bar,
           baz,
           qux
];

ObjectExpression

Examples of incorrect code for this rule with the 2, { "ObjectExpression": 1 } option:

/*eslint indent: ["error", 2, { "ObjectExpression": 1 }]*/

var foo = {
    bar: 1,
baz: 2,
      qux: 3
};

Examples of correct code for this rule with the 2, { "ObjectExpression": 1 } option:

/*eslint indent: ["error", 2, { "ObjectExpression": 1 }]*/

var foo = {
  bar: 1,
  baz: 2,
  qux: 3
};

Examples of incorrect code for this rule with the 2, { "ObjectExpression": "first" } option:

/*eslint indent: ["error", 2, {"ObjectExpression": "first"}]*/

var foo = { bar: 1,
  baz: 2 };

Examples of correct code for this rule with the 2, { "ObjectExpression": "first" } option:

/*eslint indent: ["error", 2, {"ObjectExpression": "first"}]*/

var foo = { bar: 1,
            baz: 2 };

Compatibility

Version

This rule was introduced in ESLint 4.0.0-alpha.0.

Resources