[all-commits] [llvm/llvm-project] aa56e6: [clang-tidy] Tweak 'rule of 3/5' checks to allow d...

[Roy Jacobson via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: aa56e66bf7520512fd1209cbb7d099604a5f6277
      https://github.com/llvm/llvm-project/commit/aa56e66bf7520512fd1209cbb7d099604a5f6277
  Author: Roy Jacobson <roi.jacobson1 at gmail.com>
  Date:   2023-02-26 (Sun, 26 Feb 2023)

  Changed paths:
    M clang-tools-extra/clang-tidy/cppcoreguidelines/SpecialMemberFunctionsCheck.cpp
    M clang-tools-extra/docs/clang-tidy/checks/cppcoreguidelines/special-member-functions.rst
    M clang-tools-extra/test/clang-tidy/checkers/cppcoreguidelines/special-member-functions-cxx-03.cpp
    M clang-tools-extra/test/clang-tidy/checkers/cppcoreguidelines/special-member-functions-relaxed.cpp
    M clang-tools-extra/test/clang-tidy/checkers/cppcoreguidelines/special-member-functions.cpp

  Log Message:
  -----------
  [clang-tidy] Tweak 'rule of 3/5' checks to allow defaulting a destructor outside the class.

A somewhat common code-pattern is to default a destructor in the source file and not in the header.
For example, this is the way to use smart pointers with forward-declared classes:

```c++

struct Impl;
struct A {
  ~A(); // Can't be defaulted in the header.

private:
  std::unique_ptr<Impl> impl;
};
```

To be able to use this check with this pattern, I modified the behavior with `AllowSoleDefaultDtor`
to not trigger on destructors if they aren't defined yet.
Since a declared destructor should still be defined somewhere in the program, this
won't miss bad classes, just diagnose on less translation units.

Reviewed By: carlosgalvezp

Differential Revision: https://reviews.llvm.org/D143851