[clang-tools-extra] [clang-tidy] add check to suggest replacement of nested std::min or std::max with initializer lists (PR #85572)

[Julian Schmidt via cfe-commits]

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@@ -0,0 +1,199 @@
+//===--- MinMaxUseInitializerListCheck.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 "MinMaxUseInitializerListCheck.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+#include "clang/Frontend/CompilerInstance.h"
+#include "clang/Lex/Lexer.h"
+
+using namespace clang::ast_matchers;
+
+namespace clang::tidy::modernize {
+
+MinMaxUseInitializerListCheck::MinMaxUseInitializerListCheck(
+    StringRef Name, ClangTidyContext *Context)
+    : ClangTidyCheck(Name, Context),
+      Inserter(Options.getLocalOrGlobal("IncludeStyle",
+                                        utils::IncludeSorter::IS_LLVM),
+               areDiagsSelfContained()) {}
+
+void MinMaxUseInitializerListCheck::storeOptions(
+    ClangTidyOptions::OptionMap &Opts) {
+  Options.store(Opts, "IncludeStyle", Inserter.getStyle());
+}
+
+void MinMaxUseInitializerListCheck::registerMatchers(MatchFinder *Finder) {
+  Finder->addMatcher(
+      callExpr(
+          callee(functionDecl(hasName("::std::max"))),
+          anyOf(hasArgument(
+                    0, callExpr(callee(functionDecl(hasName("::std::max"))))),
+                hasArgument(
+                    1, callExpr(callee(functionDecl(hasName("::std::max")))))),
+          unless(
+              hasParent(callExpr(callee(functionDecl(hasName("::std::max")))))))
+          .bind("topCall"),
+      this);
+
+  Finder->addMatcher(
+      callExpr(
+          callee(functionDecl(hasName("::std::min"))),
+          anyOf(hasArgument(
+                    0, callExpr(callee(functionDecl(hasName("::std::min"))))),
+                hasArgument(
+                    1, callExpr(callee(functionDecl(hasName("::std::min")))))),
+          unless(
+              hasParent(callExpr(callee(functionDecl(hasName("::std::min")))))))
+          .bind("topCall"),
+      this);
+}
+
+void MinMaxUseInitializerListCheck::registerPPCallbacks(
+    const SourceManager &SM, Preprocessor *PP, Preprocessor *ModuleExpanderPP) {
+  Inserter.registerPreprocessor(PP);
+}
+
+void MinMaxUseInitializerListCheck::check(
+    const MatchFinder::MatchResult &Match) {
+  const CallExpr *TopCall = Match.Nodes.getNodeAs<CallExpr>("topCall");
----------------
5chmidti wrote:

If the type is already on the right-hand-side, then you can use `auto` to declare the variable.

https://github.com/llvm/llvm-project/pull/85572