oxc/const-comparisons Correctness
What it does
Checks for redundant or logically impossible comparisons. This includes:
- Ineffective double comparisons against constants.
- Impossible comparisons involving constants.
- Redundant comparisons where both operands are the same (e.g., a < a).
Why is this bad?
Such comparisons can lead to confusing or incorrect logic in the program. In many cases:
- Only one of the comparisons has any effect on the result, suggesting that the programmer might have made a mistake, such as flipping one of the comparison operators or using the wrong variable.
- Comparisons like a < a or a >= a are always false or true respectively, making the logic redundant and potentially misleading.
Example
Examples of incorrect code for this rule:
javascript
status_code <= 400 && status_code > 500;
status_code < 200 && status_code <= 299;
status_code > 500 && status_code >= 500;
a < a; // Always false
a >= a; // Always trueExamples of correct code for this rule:
javascript
status_code >= 400 && status_code < 500;
500 <= status_code && 600 > status_code;
500 <= status_code && status_code <= 600;
a < b;
a <= b;