[clang-tools-extra] [clang-tidy] Add modernize-substr-to-starts-with check (PR #116033)

[via cfe-commits]

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@@ -173,7 +222,80 @@ void UseStartsEndsWithCheck::registerMatchers(MatchFinder *Finder) {
       this);
 }
 
+void UseStartsEndsWithCheck::handleSubstrMatch(const MatchFinder::MatchResult &Result) {
+  const auto *SubstrCall = Result.Nodes.getNodeAs<CXXMemberCallExpr>("substr_fun");
+  const auto *PositiveComparison = Result.Nodes.getNodeAs<Expr>("positiveComparison");
+  const auto *NegativeComparison = Result.Nodes.getNodeAs<Expr>("negativeComparison");
+  
+  if (!SubstrCall || (!PositiveComparison && !NegativeComparison))
+    return;
+
+  bool Negated = NegativeComparison != nullptr;
----------------
EugeneZelenko wrote:

```suggestion
  const bool Negated = NegativeComparison != nullptr;
```

https://github.com/llvm/llvm-project/pull/116033