[clang-tools-extra] [clang-tidy][readability-identifier-length] Add a line count threshold (PR #185319)

[Baranov Victor via cfe-commits]

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@@ -85,6 +90,28 @@ void IdentifierLengthCheck::registerMatchers(MatchFinder *Finder) {
         this);
 }
 
+static unsigned countLinesToLastUse(const VarDecl *Var,
+                                    const SourceManager *SrcMgr,
+                                    ASTContext *Ctx) {
+  const auto *ParentScope = llvm::dyn_cast<FunctionDecl>(Var->getDeclContext());
+  if (ParentScope == nullptr) {
+    return 1;
+  }
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vbvictor wrote:

I agree we should omit warning on globals. Can we add docs for it and tests.

https://github.com/llvm/llvm-project/pull/185319