In Ruby, the rule “Prefer equal? over == when comparing object_id” is important to remember because of how these two comparison methods function. The equal? method checks if the two compared references point to the exact same object, while the == method checks if the values of the two objects are the same.
This rule is crucial because when you are comparing object_id, you are actually interested in whether the two objects are the same object, not whether their values are equal. Using == can lead to unexpected results if two different objects have the same object_id.
To adhere to this rule and maintain good coding practices, always use equal? when comparing object_id. This ensures that you are accurately checking if the two objects are the same. For instance, instead of writing foo.object_id == bar.object_id, you should write foo.equal?(bar). This way, you are properly checking for object identity, not object equality.
Non-Compliant Code Examples
foo.object_id==bar.object_id
Compliant Code Examples
foo.equal?(bar)
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How to use this rule
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rulesets:- ruby-best-practices # Rules to enforce Ruby best practices.
Create a static-analysis.datadog.yml with the content above at the root of your repository
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