[clang-tools-extra] [clang-tidy] Create bugprone-incorrect-enable-shared-from-this check (PR #102299)

[Julian Schmidt via cfe-commits]

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@@ -0,0 +1,121 @@
+// RUN: %check_clang_tidy -std=c++11 %s bugprone-incorrect-enable-shared-from-this %t
+
+// NOLINTBEGIN
+namespace std {
+    template <typename T> class enable_shared_from_this {};
+} //namespace std
+// NOLINTEND
+
+class BadClassExample : std::enable_shared_from_this<BadClassExample> {};
+// CHECK-MESSAGES: :[[@LINE-1]]:7: warning: BadClassExample is not publicly inheriting from 'std::enable_shared_from_this', will cause unintended behaviour on 'shared_from_this'. fix this by making it public inheritance [bugprone-incorrect-enable-shared-from-this]
+// CHECK-FIXES: public std::enable_shared_from_this<BadClassExample>
+
+class BadClass2Example : private std::enable_shared_from_this<BadClass2Example> {};
+// CHECK-MESSAGES: :[[@LINE-1]]:7: warning: BadClass2Example is not publicly inheriting from 'std::enable_shared_from_this', will cause unintended behaviour on 'shared_from_this'. fix this by making it public inheritance [bugprone-incorrect-enable-shared-from-this]
+// CHECK-FIXES: public std::enable_shared_from_this<BadClass2Example>
+
+struct BadStructExample : private std::enable_shared_from_this<BadStructExample> {};
+// CHECK-MESSAGES: :[[@LINE-1]]:8: warning: BadStructExample is not publicly inheriting from 'std::enable_shared_from_this', will cause unintended behaviour on 'shared_from_this'. fix this by making it public inheritance [bugprone-incorrect-enable-shared-from-this]
+// CHECK-FIXES: public std::enable_shared_from_this<BadStructExample>
+
+class GoodClassExample : public std::enable_shared_from_this<GoodClassExample> {};
+
+struct GoodStructExample : public std::enable_shared_from_this<GoodStructExample> {};
+
+struct GoodStruct2Example : std::enable_shared_from_this<GoodStruct2Example> {};
+
+class dummy_class1 {};
+class dummy_class2 {};
+
+class BadMultiClassExample : std::enable_shared_from_this<BadMultiClassExample>, dummy_class1 {};
+// CHECK-MESSAGES: :[[@LINE-1]]:7: warning: BadMultiClassExample is not publicly inheriting from 'std::enable_shared_from_this', will cause unintended behaviour on 'shared_from_this'. fix this by making it public inheritance [bugprone-incorrect-enable-shared-from-this]
----------------
5chmidti wrote:

The wording of this diagnostic case can be improved:
Either

> 'std::enable_shared_from_this', which will cause unintended

or

> 'BadMultiClassExample' not publicly inheriting

https://github.com/llvm/llvm-project/pull/102299