[PATCH] D97297: [clang-tidy] Suppress reports to patternedly named parameters in 'bugprone-easily-swappable-parameters'

[Aaron Ballman via Phabricator via cfe-commits]

aaron.ballman accepted this revision.
aaron.ballman added a comment.
This revision is now accepted and ready to land.

LGTM!



================
Comment at: clang-tools-extra/clang-tidy/bugprone/EasilySwappableParametersCheck.cpp:364-365
+                                                StringRef S2) {
+  StringRef S1Prefix = S1.take_front(S1.size() - N),
+            S2Prefix = S2.take_front(S2.size() - N);
+  return S1Prefix == S2Prefix && !S1Prefix.empty();
----------------
whisperity wrote:
> aaron.ballman wrote:
> > Should we be checking that `.size() - N` doesn't cause wraparound?
> Wraparound as in underflow? Like `2 - 8` becoming multiple millions? The incoming strings are padded to the common length.
> 
> `take_xxx` won't let you go out of bounds, even if the parameter is greater than the string's length. It will just silently return the entire string.
> Wraparound as in underflow? Like 2 - 8 becoming multiple millions? The incoming strings are padded to the common length.

They are, but I didn't see anything checking that `Threshhold` (which gets passed as `N`) isn't larger than the common string length.

> take_xxx won't let you go out of bounds, even if the parameter is greater than the string's length. It will just silently return the entire string.

Aha, that's the important bit, thanks for verifying that this is safe!


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  https://reviews.llvm.org/D97297/new/

https://reviews.llvm.org/D97297