[clang-tools-extra] [clang-tidy]Add new check readability-avoid-nested-conditional-operator (PR #78022)

[Piotr Zegar via cfe-commits]

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@@ -0,0 +1,56 @@
+//===--- AvoidNestedConditionalOperatorCheck.cpp - clang-tidy ----------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "AvoidNestedConditionalOperatorCheck.h"
+#include "clang/AST/Expr.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+#include "clang/ASTMatchers/ASTMatchers.h"
+#include "clang/Basic/DiagnosticIDs.h"
+
+using namespace clang::ast_matchers;
+
+namespace clang::tidy::readability {
+
+namespace {
+constexpr const char *Description = "don't use nested conditional operator";
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PiotrZSL wrote:

anonymous namespace is not needed for constexpr, and better would be to put that text in diag, is used only once anywy, and would be easier to find.

https://github.com/llvm/llvm-project/pull/78022