Merge #21366: refactor: replace util::Ref with std::any (C++17)

916ab0195d567fd0a9097045e73a6654c453adea remove unused class util::Ref and its unit test (Sebastian Falbesoner)
8dbb87a3932f81e23ba7afd865b9aeeb535f0c20 refactor: replace util::Ref by std::any (C++17) (Sebastian Falbesoner)
95cccf8a4b392959c1fd7ec0647e04eb13880865 util: introduce helper AnyPtr to access std::any instances (Sebastian Falbesoner)

Pull request description:

  As described in `util/ref.h`: "_This implements a small subset of the functionality in C++17's std::any class, and **can be dropped when the project updates to C++17**_". For accessing the contained object of a `std::any` instance, a helper template function `AnyPtr` is introduced (thanks to ryanofsky).

ACKs for top commit:
  hebasto:
    re-ACK 916ab0195d567fd0a9097045e73a6654c453adea, with command
  ryanofsky:
    Code review ACK 916ab0195d567fd0a9097045e73a6654c453adea. Changes since last review: rebase and replacing types with `auto`. I might have used `const auto*` and `auto*` instead of plain `auto` because I think the qualifiers are useful, but this is all good.

Tree-SHA512: fe2c3e4f5726f8ad40c61128339bb24ad11d2c261f71f7b934b1efe3e3279df14046452b0d9b566917ef61d5c7e0fd96ccbf35ff810357e305710f5002c27d47

2 files changed, 3 insertions, 35 deletions

diff --git a/src/test/ref_tests.cpp b/src/test/ref_tests.cpp
deleted file mode 100644
index 0ec0799fbc..0000000000
--- a/src/test/ref_tests.cpp
+++ /dev/null
@@ -1,33 +0,0 @@
-// Copyright (c) 2020 The Bitcoin Core developers
-// Distributed under the MIT software license, see the accompanying
-// file COPYING or http://www.opensource.org/licenses/mit-license.php.
-
-#include <util/ref.h>
-
-#include <boost/test/unit_test.hpp>
-
-BOOST_AUTO_TEST_SUITE(ref_tests)
-
-BOOST_AUTO_TEST_CASE(ref_test)
-{
-    util::Ref ref;
-    BOOST_CHECK(!ref.Has<int>());
-    BOOST_CHECK_THROW(ref.Get<int>(), NonFatalCheckError);
-    int value = 5;
-    ref.Set(value);
-    BOOST_CHECK(ref.Has<int>());
-    BOOST_CHECK_EQUAL(ref.Get<int>(), 5);
-    ++ref.Get<int>();
-    BOOST_CHECK_EQUAL(ref.Get<int>(), 6);
-    BOOST_CHECK_EQUAL(value, 6);
-    ++value;
-    BOOST_CHECK_EQUAL(value, 7);
-    BOOST_CHECK_EQUAL(ref.Get<int>(), 7);
-    BOOST_CHECK(!ref.Has<bool>());
-    BOOST_CHECK_THROW(ref.Get<bool>(), NonFatalCheckError);
-    ref.Clear();
-    BOOST_CHECK(!ref.Has<int>());
-    BOOST_CHECK_THROW(ref.Get<int>(), NonFatalCheckError);
-}
-
-BOOST_AUTO_TEST_SUITE_END()
diff --git a/src/test/rpc_tests.cpp b/src/test/rpc_tests.cpp
index 2e0fc7e48f..67e70b3bc3 100644
--- a/src/test/rpc_tests.cpp
+++ b/src/test/rpc_tests.cpp
@@ -10,9 +10,10 @@
 #include <interfaces/chain.h>
 #include <node/context.h>
 #include <test/util/setup_common.h>
-#include <util/ref.h>
 #include <util/time.h>
 
+#include <any>
+
 #include <boost/algorithm/string.hpp>
 #include <boost/test/unit_test.hpp>
 
@@ -32,7 +33,7 @@ UniValue RPCTestingSetup::CallRPC(std::string args)
     boost::split(vArgs, args, boost::is_any_of(" \t"));
     std::string strMethod = vArgs[0];
     vArgs.erase(vArgs.begin());
-    util::Ref context{m_node};
+    std::any context{&m_node};
     JSONRPCRequest request(context);
     request.strMethod = strMethod;
     request.params = RPCConvertValues(strMethod, vArgs);