@stylistic/

space-before-blocks

Consistency is an important part of any style guide. While it is a personal preference where to put the opening brace of blocks, it should be consistent across a whole project. Having an inconsistent style distracts the reader from seeing the important parts of the code.

Rule Details

This rule will enforce consistency of spacing before blocks. It is only applied on blocks that don’t begin on a new line.

• This rule ignores spacing which is between => and a block. The spacing is handled by the arrow-spacing rule.
• This rule ignores spacing which is between a keyword and a block. The spacing is handled by the keyword-spacing rule.
• This rule ignores spacing which is between : of a switch case and a block. The spacing is handled by the switch-colon-spacing rule.

Options

This rule takes one argument. If it is "always" then blocks must always have at least one preceding space. If "never" then all blocks should never have any preceding space. If different spacing is desired for function blocks, keyword blocks and classes, an optional configuration object can be passed as the rule argument to configure the cases separately. If any value in the configuration object is "off", then neither style will be enforced for blocks of that kind.

( e.g. { "functions": "never", "keywords": "always", "classes": "always" } )

The default is "always".

"always"

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

/*eslint @stylistic/space-before-blocks: "error"*/

if (a)
{
    b();
}

function a()
{}

for (;;)
{
    b();
}

try {} catch(a)
{}

class Foo
{
  constructor()
{}
}

incorrect

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

/*eslint @stylistic/space-before-blocks: "error"*/

if (a) {
    b();
}

if (a) {
    b();
} else{ /*no error. this is checked by `keyword-spacing` rule.*/
    c();
}

class C {
    static{} /*no error. this is checked by `keyword-spacing` rule.*/
}

function a() {}

for (;;) {
    b();
}

try {} catch(a) {}

correct

"never"

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

/*eslint @stylistic/space-before-blocks: ["error", "never"]*/

if (a) 
{
    b();
}

function a() 
{}

for (;;) 
{
    b();
}

try {} catch(a) 
{}

incorrect

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

/*eslint @stylistic/space-before-blocks: ["error", "never"]*/

if (a){
    b();
}

function a(){}

for (;;){
    b();
}

try{} catch(a){}

class Foo{
  constructor(){}
}

correct

Examples of incorrect code for this rule when configured { "functions": "never", "keywords": "always", "classes": "never" }:

/*eslint @stylistic/space-before-blocks: ["error", { "functions": "never", "keywords": "always", "classes": "never" }]*/
/*eslint-env es6*/

function a() 
{}

try {} catch(a)
{}

class Foo{
  constructor() 
{}
}

incorrect

Examples of correct code for this rule when configured { "functions": "never", "keywords": "always", "classes": "never" }:

/*eslint @stylistic/space-before-blocks: ["error", { "functions": "never", "keywords": "always", "classes": "never" }]*/
/*eslint-env es6*/

for (;;) {
  // ...
}

describe(function(){
  // ...
});

class Foo{
  constructor(){}
}

correct

Examples of incorrect code for this rule when configured { "functions": "always", "keywords": "never", "classes": "never" }:

/*eslint @stylistic/space-before-blocks: ["error", { "functions": "always", "keywords": "never", "classes": "never" }]*/
/*eslint-env es6*/

function a()
{}

try {} catch(a) 
{}

class Foo 
{
  constructor()
{}
}

incorrect

Examples of correct code for this rule when configured { "functions": "always", "keywords": "never", "classes": "never" }:

/*eslint @stylistic/space-before-blocks: ["error", { "functions": "always", "keywords": "never", "classes": "never" }]*/
/*eslint-env es6*/

if (a){
  b();
}

var a = function() {}

class Foo{
  constructor() {}
}

correct

Examples of incorrect code for this rule when configured { "functions": "never", "keywords": "never", "classes": "always" }:

/*eslint @stylistic/space-before-blocks: ["error", { "functions": "never", "keywords": "never", "classes": "always" }]*/
/*eslint-env es6*/

class Foo
{
  constructor(){}
}

incorrect

Examples of correct code for this rule when configured { "functions": "never", "keywords": "never", "classes": "always" }:

/*eslint @stylistic/space-before-blocks: ["error", { "functions": "never", "keywords": "never", "classes": "always" }]*/
/*eslint-env es6*/

class Foo {
  constructor(){}
}

correct

When Not To Use It

You can turn this rule off if you are not concerned with the consistency of spacing before blocks.

TypeScript Specific

ts/space-before-blocks

/*eslint @stylistic/ts/space-before-blocks: "error"*/

enum Breakpoint{
  Large, Mediu
m
;
}

interface State{
  currentBreakpoint: Breakpoint;
}

/*eslint @stylistic/ts/space-before-blocks: "error"*/

enum Breakpoint {
  Large, Mediu
m
;
}

interface State {
  currentBreakpoint: Breakpoint;
}

Options

In case a more specific options object is passed these blocks will follow classes configuration option.

correct

incorrect