[PATCH] D89332: [clang-tidy] performance-unnecessary-copy-initialization: Always allow std::function to be copied.

[Felix Berger via Phabricator via cfe-commits]

flx updated this revision to Diff 299471.
flx added a comment.

Use hasName matcher on the declaration of the canonical type.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D89332/new/

https://reviews.llvm.org/D89332

Files:
  clang-tools-extra/clang-tidy/performance/UnnecessaryCopyInitialization.cpp
  clang-tools-extra/test/clang-tidy/checkers/performance-unnecessary-copy-initialization.cpp


Index: clang-tools-extra/test/clang-tidy/checkers/performance-unnecessary-copy-initialization.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/performance-unnecessary-copy-initialization.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/performance-unnecessary-copy-initialization.cpp
@@ -405,3 +405,41 @@
   ExpensiveToCopyType Orig;
   const ExpensiveToCopyType Copy = freeFunctionWithDefaultArg(&Orig);
 }
+
+namespace std {
+inline namespace __1 {
+
+template <class>
+class function;
+template <class R, class... Args>
+class function<R(Args...)> {
+public:
+  function();
+  function(const function &other);
+  R operator()(Args &&...args) const;
+};
+
+} // namespace __1
+} // namespace std
+
+void negativeStdFunction() {
+  std::function<int()> Orig;
+  std::function<int()> Copy = Orig;
+  int i = Orig();
+}
+
+using Functor = std::function<int()>;
+
+void negativeAliasedStdFunction() {
+  Functor Orig;
+  Functor Copy = Orig;
+  int i = Orig();
+}
+
+typedef std::function<int()> TypedefFunc;
+
+void negativeTypedefedStdFunction() {
+  TypedefFunc Orig;
+  TypedefFunc Copy = Orig;
+  int i = Orig();
+}
Index: clang-tools-extra/clang-tidy/performance/UnnecessaryCopyInitialization.cpp
===================================================================
--- clang-tools-extra/clang-tidy/performance/UnnecessaryCopyInitialization.cpp
+++ clang-tools-extra/clang-tidy/performance/UnnecessaryCopyInitialization.cpp
@@ -40,7 +40,8 @@
       AllowedTypes(
           utils::options::parseStringList(Options.get("AllowedTypes", ""))) {}
 
-void UnnecessaryCopyInitialization::registerMatchers(MatchFinder *Finder) {
+void UnnecessaryCopyInitialization::registerMatchers(
+    internal::MatchFinder *Finder) {
   auto ConstReference = referenceType(pointee(qualType(isConstQualified())));
 
   // Match method call expressions where the `this` argument is only used as
@@ -57,17 +58,20 @@
                unless(callee(cxxMethodDecl())))
           .bind("initFunctionCall");
 
-  auto localVarCopiedFrom = [this](const internal::Matcher<Expr> &CopyCtorArg) {
+  auto localVarCopiedFrom = [this](const Matcher<Expr> &CopyCtorArg) {
     return compoundStmt(
                forEachDescendant(
                    declStmt(
                        has(varDecl(hasLocalStorage(),
                                    hasType(qualType(
-                                       hasCanonicalType(
-                                           matchers::isExpensiveToCopy()),
+                                       hasCanonicalType(allOf(
+                                           matchers::isExpensiveToCopy(),
+                                           unless(hasDeclaration(namedDecl(
+                                               hasName("::std::function")))))),
                                        unless(hasDeclaration(namedDecl(
-                                           matchers::matchesAnyListedName(
-                                               AllowedTypes)))))),
+                                           anyOf(matchers::matchesAnyListedName(
+                                                     AllowedTypes),
+                                                 isStdFunction())))))),
                                    unless(isImplicit()),
                                    hasInitializer(traverse(
                                        ast_type_traits::TK_AsIs,


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