[clang-tools-extra] [clang-tidy] Don't report unnamed params for misc-const-correctness (PR #184388)

[Baranov Victor via cfe-commits]

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@@ -207,6 +207,13 @@ void ConstCorrectnessCheck::check(const MatchFinder::MatchResult &Result) {
 
   assert(Variable && LocalScope && Function);
 
+  // If a variable (e.g. function parameter) is unnamed, don't report it. Being
+  // unnamed already guarantees that the variable can't be accessed, so
+  // 'const'ness (can't be modified) doesn't add extra information. Also, the
+  // messages would be awkward in this case.
+  if (Variable->getDeclName().isIdentifier() && Variable->getName().empty())
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vbvictor wrote:

Hm, thats unfortunate but understandable.
Can we then make a custom `isUnnamed` matcher with `AST_MATCHER()` macro that will essentially do what you wrote inside `check()`. And Leave a `TODO` to merge with `hasName` or move to general matchers as is.

https://github.com/llvm/llvm-project/pull/184388