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oxc/bad-comparison-sequence Correctness

This rule is turned on by default.

What it does

This rule applies when the comparison operator is applied two or more times in a row.

Why is this bad?

Because comparison operator is a binary operator, it is impossible to compare three or more operands at once. If comparison operator is used to compare three or more operands, only the first two operands are compared and the rest is compared with its result of boolean type.

Examples

Examples of incorrect code for this rule:

javascript
if (a == b == c) {
  console.log("a, b, and c are the same");
}

Examples of correct code for this rule:

javascript
if (a == b && b == c) {
  console.log("a, b, and c are the same");
}

How to use

To enable this rule using the config file or in the CLI, you can use:

json
{
  "rules": {
    "oxc/bad-comparison-sequence": "error"
  }
}
bash
oxlint --deny oxc/bad-comparison-sequence

References

Released under the MIT License.