[clang-tools-extra] [clang-tidy] Support direct initialization in modernize smart pointer (PR #154732)

[Liu Ke via cfe-commits]

https://github.com/Sockke created https://github.com/llvm/llvm-project/pull/154732

Support for direct initialization detection in modernize smart pointer checks.


>From d09ad7261bf36a941ee07596f64a8ac02b7be54a Mon Sep 17 00:00:00 2001
From: Sockke <liuke.gehry at bytedance.com>
Date: Thu, 21 Aug 2025 18:42:20 +0800
Subject: [PATCH] [clang-tidy] Support direct initialization in modernize smart
 pointer

---
 .../modernize/MakeSmartPtrCheck.cpp           | 29 ++++++++++---------
 .../checkers/modernize/make-shared.cpp        |  2 ++
 .../checkers/modernize/make-unique.cpp        |  2 ++
 3 files changed, 20 insertions(+), 13 deletions(-)

diff --git a/clang-tools-extra/clang-tidy/modernize/MakeSmartPtrCheck.cpp b/clang-tools-extra/clang-tidy/modernize/MakeSmartPtrCheck.cpp
index deef3586628c6..b7e7d5fc049a4 100644
--- a/clang-tools-extra/clang-tidy/modernize/MakeSmartPtrCheck.cpp
+++ b/clang-tools-extra/clang-tidy/modernize/MakeSmartPtrCheck.cpp
@@ -81,18 +81,16 @@ void MakeSmartPtrCheck::registerMatchers(ast_matchers::MatchFinder *Finder) {
   auto IsPlacement = hasAnyPlacementArg(anything());
 
   Finder->addMatcher(
-      traverse(
-          TK_AsIs,
-          cxxBindTemporaryExpr(has(ignoringParenImpCasts(
-              cxxConstructExpr(
-                  hasType(getSmartPointerTypeMatcher()), argumentCountIs(1),
-                  hasArgument(
-                      0, cxxNewExpr(hasType(pointsTo(qualType(hasCanonicalType(
-                                        equalsBoundNode(PointerType))))),
-                                    CanCallCtor, unless(IsPlacement))
-                             .bind(NewExpression)),
-                  unless(isInTemplateInstantiation()))
-                  .bind(ConstructorCall))))),
+      traverse(TK_AsIs,
+               cxxConstructExpr(
+                   hasType(getSmartPointerTypeMatcher()), argumentCountIs(1),
+                   hasArgument(
+                       0, cxxNewExpr(hasType(pointsTo(qualType(hasCanonicalType(
+                                         equalsBoundNode(PointerType))))),
+                                     CanCallCtor, unless(IsPlacement))
+                              .bind(NewExpression)),
+                   unless(isInTemplateInstantiation()))
+                   .bind(ConstructorCall)),
       this);
 
   Finder->addMatcher(
@@ -190,9 +188,14 @@ void MakeSmartPtrCheck::checkConstruct(SourceManager &SM, ASTContext *Ctx,
     ConstructCallEnd = ConstructCallStart.getLocWithOffset(LAngle);
   }
 
+  std::string FinalMakeSmartPtrFunctionName = MakeSmartPtrFunctionName.str();
+  auto Parents = Ctx->getParents(*Construct);
+  if (!Parents.empty() && Parents[0].get<clang::Decl>())
+      FinalMakeSmartPtrFunctionName = ExprStr.str() + " = " + MakeSmartPtrFunctionName.str();
+
   Diag << FixItHint::CreateReplacement(
       CharSourceRange::getCharRange(ConstructCallStart, ConstructCallEnd),
-      MakeSmartPtrFunctionName);
+      FinalMakeSmartPtrFunctionName);
 
   // If the smart_ptr is built with brace enclosed direct initialization, use
   // parenthesis instead.
diff --git a/clang-tools-extra/test/clang-tidy/checkers/modernize/make-shared.cpp b/clang-tools-extra/test/clang-tidy/checkers/modernize/make-shared.cpp
index e57f45c4127f9..65ece773b7c1f 100644
--- a/clang-tools-extra/test/clang-tidy/checkers/modernize/make-shared.cpp
+++ b/clang-tools-extra/test/clang-tidy/checkers/modernize/make-shared.cpp
@@ -109,6 +109,8 @@ void basic() {
   }
 
   std::shared_ptr<int> R(new int());
+  // CHECK-MESSAGES: :[[@LINE-1]]:24: warning: use std::make_shared instead
+  // CHECK-FIXES: std::shared_ptr<int> R = std::make_shared<int>();
   std::shared_ptr<int> S(new int);
 
   // Create the shared_ptr as a parameter to a function.
diff --git a/clang-tools-extra/test/clang-tidy/checkers/modernize/make-unique.cpp b/clang-tools-extra/test/clang-tidy/checkers/modernize/make-unique.cpp
index e665ca0a15a68..13103c735276a 100644
--- a/clang-tools-extra/test/clang-tidy/checkers/modernize/make-unique.cpp
+++ b/clang-tools-extra/test/clang-tidy/checkers/modernize/make-unique.cpp
@@ -154,6 +154,8 @@ void basic() {
   }
 
   std::unique_ptr<int> R(new int());
+  // CHECK-MESSAGES: :[[@LINE-1]]:24: warning: use std::make_unique instead
+  // CHECK-FIXES: std::unique_ptr<int> R = std::make_unique<int>();
   std::unique_ptr<int> S(new int);
 
   // Create the unique_ptr as a parameter to a function.