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Lint Rule noNegationElse

website/src/pages/lint/rules/noNegationElse.md

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noNegationElse (since v0.7.0)

Disallow negation in the condition of an if statement if it has an else clause

Examples

Invalid

jsx
if (!true) {consequent;} else {alternate;}
<pre class="language-text"><code class="language-text">style/noNegationElse.js:1:1 <a href="https://docs.rome.tools/lint/rules/noNegationElse">lint/style/noNegationElse</a> <span style="color: #000; background-color: #ddd;"> FIXABLE </span> ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ <strong><span style="color: Orange;"> </span></strong><strong><span style="color: Orange;">⚠</span></strong> <span style="color: Orange;">Invert blocks when performing a negation test.</span> <strong><span style="color: Tomato;"> </span></strong><strong><span style="color: Tomato;">&gt;</span></strong> <strong>1 │ </strong>if (!true) {consequent;} else {alternate;} <strong> │ </strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong> <strong>2 │ </strong> <strong><span style="color: rgb(38, 148, 255);"> </span></strong><strong><span style="color: rgb(38, 148, 255);">ℹ</span></strong> <span style="color: rgb(38, 148, 255);">Suggested fix</span><span style="color: rgb(38, 148, 255);">: </span><span style="color: rgb(38, 148, 255);">Exchange alternate and consequent of the node</span> <strong>1</strong> <strong> │ </strong><span style="color: Tomato;">-</span> <span style="color: Tomato;">i</span><span style="color: Tomato;">f</span><span style="color: Tomato;"><span style="opacity: 0.8;">·</span></span><span style="color: Tomato;">(</span><span style="color: Tomato;"><strong>!</strong></span><span style="color: Tomato;">t</span><span style="color: Tomato;">r</span><span style="color: Tomato;">u</span><span style="color: Tomato;">e</span><span style="color: Tomato;">)</span><span style="color: Tomato;"><span style="opacity: 0.8;">·</span></span><span style="color: Tomato;">{</span><span style="color: Tomato;"><strong>c</strong></span><span style="color: Tomato;"><strong>o</strong></span><span style="color: Tomato;"><strong>n</strong></span><span style="color: Tomato;"><strong>s</strong></span><span style="color: Tomato;"><strong>e</strong></span><span style="color: Tomato;"><strong>q</strong></span><span style="color: Tomato;"><strong>u</strong></span><span style="color: Tomato;"><strong>e</strong></span><span style="color: Tomato;"><strong>n</strong></span><span style="color: Tomato;"><strong>t</strong></span><span style="color: Tomato;">;</span><span style="color: Tomato;">}</span><span style="color: Tomato;"><span style="opacity: 0.8;">·</span></span><span style="color: Tomato;">e</span><span style="color: Tomato;">l</span><span style="color: Tomato;">s</span><span style="color: Tomato;">e</span><span style="color: Tomato;"><span style="opacity: 0.8;">·</span></span><span style="color: Tomato;">{</span><span style="color: Tomato;"><strong>a</strong></span><span style="color: Tomato;"><strong>l</strong></span><span style="color: Tomato;"><strong>t</strong></span><span style="color: Tomato;"><strong>e</strong></span><span style="color: Tomato;"><strong>r</strong></span><span style="color: Tomato;"><strong>n</strong></span><span style="color: Tomato;"><strong>a</strong></span><span style="color: Tomato;"><strong>t</strong></span><span style="color: Tomato;"><strong>e</strong></span><span style="color: Tomato;">;</span><span style="color: Tomato;">}</span> <strong>1</strong><strong> │ </strong><span style="color: MediumSeaGreen;">+</span> <span style="color: MediumSeaGreen;">i</span><span style="color: MediumSeaGreen;">f</span><span style="color: MediumSeaGreen;"><span style="opacity: 0.8;">·</span></span><span style="color: MediumSeaGreen;">(</span><span style="color: MediumSeaGreen;">t</span><span style="color: MediumSeaGreen;">r</span><span style="color: MediumSeaGreen;">u</span><span style="color: MediumSeaGreen;">e</span><span style="color: MediumSeaGreen;">)</span><span style="color: MediumSeaGreen;"><span style="opacity: 0.8;">·</span></span><span style="color: MediumSeaGreen;">{</span><span style="color: MediumSeaGreen;"><strong>a</strong></span><span style="color: MediumSeaGreen;"><strong>l</strong></span><span style="color: MediumSeaGreen;"><strong>t</strong></span><span style="color: MediumSeaGreen;"><strong>e</strong></span><span style="color: MediumSeaGreen;"><strong>r</strong></span><span style="color: MediumSeaGreen;"><strong>n</strong></span><span style="color: MediumSeaGreen;"><strong>a</strong></span><span style="color: MediumSeaGreen;"><strong>t</strong></span><span style="color: MediumSeaGreen;"><strong>e</strong></span><span style="color: MediumSeaGreen;">;</span><span style="color: MediumSeaGreen;">}</span><span style="color: MediumSeaGreen;"><span style="opacity: 0.8;">·</span></span><span style="color: MediumSeaGreen;">e</span><span style="color: MediumSeaGreen;">l</span><span style="color: MediumSeaGreen;">s</span><span style="color: MediumSeaGreen;">e</span><span style="color: MediumSeaGreen;"><span style="opacity: 0.8;">·</span></span><span style="color: MediumSeaGreen;">{</span><span style="color: MediumSeaGreen;"><strong>c</strong></span><span style="color: MediumSeaGreen;"><strong>o</strong></span><span style="color: MediumSeaGreen;"><strong>n</strong></span><span style="color: MediumSeaGreen;"><strong>s</strong></span><span style="color: MediumSeaGreen;"><strong>e</strong></span><span style="color: MediumSeaGreen;"><strong>q</strong></span><span style="color: MediumSeaGreen;"><strong>u</strong></span><span style="color: MediumSeaGreen;"><strong>e</strong></span><span style="color: MediumSeaGreen;"><strong>n</strong></span><span style="color: MediumSeaGreen;"><strong>t</strong></span><span style="color: MediumSeaGreen;">;</span><span style="color: MediumSeaGreen;">}</span> <strong>2</strong> <strong>2</strong><strong> │ </strong> </code></pre>
jsx
!true ? consequent : alternate
<pre class="language-text"><code class="language-text">style/noNegationElse.js:1:1 <a href="https://docs.rome.tools/lint/rules/noNegationElse">lint/style/noNegationElse</a> <span style="color: #000; background-color: #ddd;"> FIXABLE </span> ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ <strong><span style="color: Orange;"> </span></strong><strong><span style="color: Orange;">⚠</span></strong> <span style="color: Orange;">Invert blocks when performing a negation test.</span> <strong><span style="color: Tomato;"> </span></strong><strong><span style="color: Tomato;">&gt;</span></strong> <strong>1 │ </strong>!true ? consequent : alternate <strong> │ </strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong> <strong>2 │ </strong> <strong><span style="color: rgb(38, 148, 255);"> </span></strong><strong><span style="color: rgb(38, 148, 255);">ℹ</span></strong> <span style="color: rgb(38, 148, 255);">Suggested fix</span><span style="color: rgb(38, 148, 255);">: </span><span style="color: rgb(38, 148, 255);">Exchange alternate and consequent of the node</span> <strong>1</strong> <strong> │ </strong><span style="color: Tomato;">-</span> <span style="color: Tomato;"><strong>!</strong></span><span style="color: Tomato;">t</span><span style="color: Tomato;">r</span><span style="color: Tomato;">u</span><span style="color: Tomato;">e</span><span style="color: Tomato;"><span style="opacity: 0.8;">·</span></span><span style="color: Tomato;">?</span><span style="color: Tomato;"><span style="opacity: 0.8;">·</span></span><span style="color: Tomato;"><strong>c</strong></span><span style="color: Tomato;"><strong>o</strong></span><span style="color: Tomato;"><strong>n</strong></span><span style="color: Tomato;"><strong>s</strong></span><span style="color: Tomato;"><strong>e</strong></span><span style="color: Tomato;"><strong>q</strong></span><span style="color: Tomato;"><strong>u</strong></span><span style="color: Tomato;"><strong>e</strong></span><span style="color: Tomato;"><strong>n</strong></span><span style="color: Tomato;"><strong>t</strong></span><span style="color: Tomato;"><span style="opacity: 0.8;">·</span></span><span style="color: Tomato;">:</span><span style="color: Tomato;"><span style="opacity: 0.8;">·</span></span><span style="color: Tomato;"><strong>a</strong></span><span style="color: Tomato;"><strong>l</strong></span><span style="color: Tomato;"><strong>t</strong></span><span style="color: Tomato;"><strong>e</strong></span><span style="color: Tomato;"><strong>r</strong></span><span style="color: Tomato;"><strong>n</strong></span><span style="color: Tomato;"><strong>a</strong></span><span style="color: Tomato;"><strong>t</strong></span><span style="color: Tomato;"><strong>e</strong></span> <strong>1</strong><strong> │ </strong><span style="color: MediumSeaGreen;">+</span> <span style="color: MediumSeaGreen;">t</span><span style="color: MediumSeaGreen;">r</span><span style="color: MediumSeaGreen;">u</span><span style="color: MediumSeaGreen;">e</span><span style="color: MediumSeaGreen;"><span style="opacity: 0.8;">·</span></span><span style="color: MediumSeaGreen;">?</span><span style="color: MediumSeaGreen;"><span style="opacity: 0.8;">·</span></span><span style="color: MediumSeaGreen;"><strong>a</strong></span><span style="color: MediumSeaGreen;"><strong>l</strong></span><span style="color: MediumSeaGreen;"><strong>t</strong></span><span style="color: MediumSeaGreen;"><strong>e</strong></span><span style="color: MediumSeaGreen;"><strong>r</strong></span><span style="color: MediumSeaGreen;"><strong>n</strong></span><span style="color: MediumSeaGreen;"><strong>a</strong></span><span style="color: MediumSeaGreen;"><strong>t</strong></span><span style="color: MediumSeaGreen;"><strong>e</strong></span><span style="color: MediumSeaGreen;"><span style="opacity: 0.8;">·</span></span><span style="color: MediumSeaGreen;">:</span><span style="color: MediumSeaGreen;"><span style="opacity: 0.8;">·</span></span><span style="color: MediumSeaGreen;"><strong>c</strong></span><span style="color: MediumSeaGreen;"><strong>o</strong></span><span style="color: MediumSeaGreen;"><strong>n</strong></span><span style="color: MediumSeaGreen;"><strong>s</strong></span><span style="color: MediumSeaGreen;"><strong>e</strong></span><span style="color: MediumSeaGreen;"><strong>q</strong></span><span style="color: MediumSeaGreen;"><strong>u</strong></span><span style="color: MediumSeaGreen;"><strong>e</strong></span><span style="color: MediumSeaGreen;"><strong>n</strong></span><span style="color: MediumSeaGreen;"><strong>t</strong></span> <strong>2</strong> <strong>2</strong><strong> │ </strong> </code></pre>

Valid

jsx
if (!true) {consequent;}
jsx
true ? consequent : alternate