add tests for common invalid cases

jsx-eslint · Apr 25, 2022 · 51068b3 · 51068b3
1 parent 2429bcc
commit 51068b3
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diff --git a/docs/rules/jsx-no-leaked-zero.md b/docs/rules/jsx-no-leaked-zero.md
@@ -182,3 +182,4 @@ If you are working in a typed-codebase which encourages you to always use boolea
 
 - [React docs: Inline If with Logical && Operator](https://reactjs.org/docs/conditional-rendering.html#inline-if-with-logical--operator)
 - [Good advice on JSX conditionals - Beware of zero](https://thoughtspile.github.io/2022/01/17/jsx-conditionals/)
+- [Twitter: rendering falsy values in React and React Native](https://twitter.com/kadikraman/status/1507654900376875011?s=21&t=elEXXbHhzWthrgKaPRMjNg)
diff --git a/tests/lib/rules/jsx-no-leaked-zero.js b/tests/lib/rules/jsx-no-leaked-zero.js
@@ -127,6 +127,49 @@ ruleTester.run('jsx-no-leaked-zero', rule, {
   ]),
 
   invalid: parsers.all([
+    // Common invalid cases with default options
+    {
+      code: `
+      const Example = () => {
+        return (
+          <>
+            {0 && <Something/>}
+            {'' && <Something/>}
+            {NaN && <Something/>}
+          </>
+        )
+      }
+      `,
+      errors: [
+        {
+          message: 'Potential numeric evaluation resulting in an unintentionally rendered `0`',
+          line: 5,
+          column: 14,
+        },
+        {
+          message: 'Potential numeric evaluation resulting in an unintentionally rendered `0`',
+          line: 6,
+          column: 14,
+        },
+        {
+          message: 'Potential numeric evaluation resulting in an unintentionally rendered `0`',
+          line: 7,
+          column: 14,
+        },
+      ],
+      output: `
+      const Example = () => {
+        return (
+          <>
+            {0 ? <Something/> : null}
+            {'' ? <Something/> : null}
+            {NaN ? <Something/> : null}
+          </>
+        )
+      }
+      `,
+    },
+
     // Invalid tests with both fix strategies (default)
     {
       code: `