[PATCH] D39121: [clang-tidy] Misplaced Operator in Strlen in Alloc

[Aaron Ballman via Phabricator via cfe-commits]

aaron.ballman added a comment.

In https://reviews.llvm.org/D39121#910802, @baloghadamsoftware wrote:

> I thought on something like this, but I still do not like my phrasing:
>
> "Addition operator is applied to the argument of strlen(). instead of its result; move the '+ 1' outside of the call. (Or, if it is intentional then surround the addition subexpression with parentheses to silence this warning)."
>
> Any better ideas?


Unfortunately, that is way too long of a diagnostic. We don't have hard and fast rules about diagnostic lengths, but (a) we don't use complete sentences for diagnostics, and (b) I would guesstimate that we usually try to keep them 80 characters or less (excluding expanded identifiers) and this one is 219 characters long (not counting `strlen()`).

Once we have some concrete numbers about how often this diagnostic triggers (true and false positives), that may help us pick a better approach. For instance, if this doesn't trigger any diagnostics across several large code bases, we may decide to not have any fix-it and simply tell the user `addition operator is applied to the argument of 'strlen()' instead of its result`. It'd be unfortunate not to tell the user what to do about it, but since it likely doesn't come up in practice all that often we can point any confused users to the documentation. However, if the numbers show that this comes up frequently (with true or false positives), we may go a different route.


https://reviews.llvm.org/D39121