eslint-plugin-react/docs/rules/jsx-tag-spacing.md

Validate whitespace in and around the JSX opening and closing brackets (react/jsx-tag-spacing)

Enforce or forbid spaces after the opening bracket, before the closing bracket, before the closing bracket of self-closing elements, and between the angle bracket and slash of JSX closing or self-closing elements.

Fixable: This rule is automatically fixable using the --fix flag on the command line.

Rule Details

This rule checks the whitespace inside and surrounding the JSX syntactic elements.

This rule takes one argument, an object with 4 possible keys: closingSlash, beforeSelfClosing, afterOpening, and beforeClosing. Each key can receive the value "allow" to disable that specific check.

The default values are:

{
  "closingSlash": "never",
  "beforeSelfClosing": "always",
  "afterOpening": "never",
  "beforeClosing": "allow"
}

The options for each sub-option are documented in the following subsections.

closingSlash

This check can be set to "always", "never" or "allow" (to disable it).

If it is "never", the check warns whenever a space is separating the two characters in the JSX tokens </ and />. If it is "always" then it warns whenever a space is missing separating the mentioned two characters. The default value of this check is "never".

The following patterns are considered warnings when configured "never":

<App/ >
<input/
>
<Provider>< /Provider>

The following patterns are not considered warnings when configured "never":

<App/>
<input/>
<Provider></Provider>

The following patterns are considered warnings when configured "always":

<Hello/>
<Goodbye></Goodbye>

The following patterns are not considered warnings when configured "always":

<Hello/ >
<Goodbye>< /Goodbye>

beforeSelfClosing

This check can be set to "always", "never" or "allow" (to disable it).

If it is "always", the check warns whenever a space is missing before the closing bracket. If "never" then it warns if a space is present before the closing bracket. The default value of this check is "always".

The following patterns are considered warnings when configured "always":

<Hello/>
<Hello firstname="John"/>

The following patterns are not considered warnings when configured "always":

<Hello />
<Hello firstName="John" />
<Hello
  firstName="John"
  lastName="Smith"
/>

The following patterns are considered warnings when configured "never":

<Hello />
<Hello firstName="John" />

The following patterns are not considered warnings when configured "never":

<Hello/>
<Hello firstname="John"/>
<Hello
  firstName="John"
  lastName="Smith"
/>

afterOpening

This check can be set to "always", "never", "allow-multiline" or "allow" (to disable it).

If it is "always", the check warns whenever a space is missing after the opening bracket of either a JSX opening element or closing element. If "never" then it warns if a space is present after the opening bracket of either a JSX opening element or closing element. If "allow-multiline" then it behaves like "never", but allows if the separator includes a newline character. The default value of this check is "never".

The following patterns are considered warnings when configured "always":

<Hello></Hello>
<Hello firstname="John"/>
<Hello
  firstName="John"
  lastName="Smith"
/>

The following patterns are not considered warnings when configured "always":

< Hello></ Hello>
< Hello firstName="John"/>
<
  Hello
  firstName="John"
  lastName="Smith"
/>

The following patterns are considered warnings when configured "never":

< Hello></ Hello>
< Hello firstName="John"/>
<
  Hello
  firstName="John"
  lastName="Smith"
/>

The following patterns are not considered warnings when configured "never":

<Hello></Hello>
<Hello firstname="John"/>
<Hello
  firstName="John"
  lastName="Smith"
/>

The following patterns are considered warnings when configured "allow-multiline":

< Hello></ Hello>
< Hello firstName="John"/>
< Hello
  firstName="John"
  lastName="Smith"
/>

The following patterns are not considered warnings when configured "allow-multiline":

<Hello></Hello>
<Hello firstName="John"/>
<
  Hello
  firstName="John"
  lastName="Smith"
/>

beforeClosing

This check can be set to "always", "never", or "allow" (to disable it).

If it is "always" the check warns whenever whitespace is missing before the closing bracket of a JSX opening element or whenever a space is missing before the closing bracket closing element. If "never", then it warns if a space is present before the closing bracket of either a JSX opening element or closing element. This rule will never warn for self closing JSX elements. The default value of this check is "allow".

The following patterns are considered warnings when configured "always":

<Hello></Hello>
<Hello></Hello >
<Hello ></Hello>

The following patterns are not considered warnings when configured "always":

<Hello ></Hello >
<Hello
  firstName="John"
>
</Hello >

The following patterns are considered warnings when configured "never":

<Hello ></Hello>
<Hello></Hello >
<Hello ></Hello >

The following patterns are not considered warnings when configured "never":

<Hello></Hello>
<Hello
  firstName="John"
>
</Hello>

When Not To Use It

You can turn this rule off if you are not concerned with the consistency of spacing in or around JSX brackets.