Hello thank you for providing such a helpful tool. Rule S6606 (JS/TS) suggests to “Prefer using nullish coalescing operator (??) instead of a logical or (||), as it is a safer operator”. The operators have different behavior. [image] Nullish coalescing operator (??) - JavaScript | MDN …

Hello @paco , thanks for reporting this. Indeed seems the rule is not properly checking the whole union. I’ve opened a ticket to fix this behavior. Thanks Victor

[image] paco: false ?? 'text' returns ‘text’ false || 'text' returns ‘false’ Hi, I think in typing, you mixed up the return values for this part of your post. It should be the below instead. It would be nice if you modify it so as to minimize confusion for others. Thanks. false ?? 'text' …

That’s correct, unfortunately I am not able to modify or edit the post. Maybe because it is my first post or something. Funny enough I can edit this reply.

Edited, thanks for the heads up @itunuloluwa . Anyway we got the message :slight_smile:

This is also an issue when using a ternary to check if something is exactly undefined or exactly null: let x = null; // intentionally null, rather than undefined let y = x === undefined ? 100 : x.value; // causes S6606 but should not There are times when it’s important to check if a value is exact…

I’m also seeing this. The irony being suggesting the replacement is safer but actually making this change is often dangerous and changes behaviour.

FYI: FP suggesting nullish coalescing operator - #7 by michal.zgliczynski

So now it’s a couple of years later and nothing has happened. I can’t see why anyone would prefer a empty string for instance when somevariable ?? ‘default’ , while somevariable || ‘default’ works as expected. And those that really want ‘’ then simply variable||‘’ ! I would hope at least chec…

Hey @Sten_W I believe a PR was merged to fix this 17 days ago [image] FP suggesting nullish coalescing operator Report False-positive / False-negative... Hello @Alain_Picard , Based on your and other community posts, we are making this rules less strict as in the origina…

JS/TS rule S6606 suggestion to replace || with ? is ambiguous

SonarQube for IDE

Colin (Colin) July 4, 2025, 8:34pm 14

Hey @Sten_W

I believe a PR was merged to fix this 17 days ago

So we shouldn’t be far away from cutting a new version of SonarJS, which will then roll onto SonarQube Cloud and SonarQube Server/Community Build (probably in that order)

Sorry it has taken a while, but hopefully this is all resolved soon!

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JS/TS rule S6606 suggestion to replace || with ? is ambiguous

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