0bbdb53a0c
Co-authored-by: Amélie Renard <44666826+amelie-renard-sonarsource@users.noreply.github.com>
32 lines
840 B
Plaintext
32 lines
840 B
Plaintext
== Why is this an issue?
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Most checks against an `indexOf` value compare it with -1 because 0 is a valid index. Checking against `> 0` ignores the first element, which is likely a bug.
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[source,javascript]
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----
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var arr = ["blue", "red"];
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if (arr.indexOf("blue") > 0) { // Noncompliant
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// ...
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}
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----
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Moreover, if the intent is merely to check the presence of the element, and if your browser version supports it, consider using `includes` instead.
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[source,javascript]
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----
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var arr = ["blue", "red"];
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if (arr.includes("blue")) {
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// ...
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}
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----
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This rule raises an issue when an `indexOf` value retrieved from an array is tested against `> 0`.
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== Resources
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https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/includes[Array.prototype.includes()] documentation at MDN
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include::../rspecator.adoc[]
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