💅 lint/complexity/noUselessFragments recommends removing useful fragments

[Lordfirespeed]

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  Enabled rules:
  performance/noDelete
  suspicious/noCatchAssign
  suspicious/noUnsafeNegation
  complexity/useLiteralKeys
  style/useImportType
  complexity/noMultipleSpacesInRegularExpressionLiterals
  a11y/useValidLang
  complexity/noUselessEmptyExport
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  correctness/noConstantCondition
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  suspicious/noDuplicateParameters
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  correctness/noUnknownProperty
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  complexity/noUselessTernary
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  suspicious/noCompareNegZero
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  correctness/noSwitchDeclarations
  a11y/noAutofocus
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  suspicious/noControlCharactersInRegex
  complexity/noUselessTypeConstraint
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  complexity/noUselessRename
  style/useNumberNamespace
  complexity/noUselessConstructor
  a11y/noAccessKey
  style/useExponentiationOperator
  style/noUnusedTemplateLiteral
  complexity/noUselessSwitchCase
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  a11y/noNoninteractiveElementToInteractiveRole
  style/noCommaOperator
  suspicious/noDuplicateAtImportRules
  suspicious/useIsArray
  a11y/noHeaderScope
  complexity/noUselessFragments
  suspicious/noMisrefactoredShorthandAssign
  complexity/noForEach
  suspicious/noClassAssign
  suspicious/noEmptyBlock
  suspicious/noFunctionAssign

Workspace:
  Open Documents:               0

Rule name

lint/complexity/noUselessFragments

Playground link

Link

Expected result

Fragments containing HTML escapes (e.g.  ) inside expression escapes { ... } should not be considered useless.

Code of Conduct

• I agree to follow Biome's Code of Conduct

[elawad]

Ran into the same issue. In an expression you can use \u00a0.

[ematipico]

Is there a reason why you use that instead of <>{" "}</>?

[Lordfirespeed]

Is there a reason why you use that instead of <>{" "}</>?

My phone has actually perfectly demoed why:

Regular space can cause unwanted line-breaks.

[ematipico]

But do you have a demo in a react JSX project that causes that?

[Lordfirespeed]

I don't see why the playground link supplied with the issue is insufficient

[ematipico]

I don't see why the playground link supplied with the issue is insufficient

Two reasons:

• I want to understand the use case
• I didn't understand the answer to my initial question, because I don't understand how GitHub rendering some markdown is related to JSX. That's why asked for a reproduction, that shows the differences

[Lordfirespeed]

I want to understand the use case

Here's one:

import * as React from "react"

const myStrings = [ "foo", "bar", undefined, "baz" ] as const

export default function TestPage() {
  return <div>
    {myStrings.map((value, index) =>
      <div>
        {value ?? <>&nbsp;</>}
      </div>
    )}
  </div>
}

The blank line is desired. With " ", the space is perceived by the HTML parser as structurally insignificant whitespace, so its enclosing <div /> is considered empty and does not render at all.

I hope you understand this is just one example, and   can be used to ensure a (blank) line-height is rendered in myriad scenarios.

I don't understand how GitHub rendering some markdown is related to JSX

That was something of a jest on my part, so I'm sorry it confused you.
You intended to convey <>{" "}</>but the content appeared to me as <>{" "}</>, which illustrates why the use of   can be necessary - I found that ironic.