From 035449a932690214b6df77a2c2e5d118dacb6c87 Mon Sep 17 00:00:00 2001
From: Lin Zhihao <59785146+LinZhihao-723@users.noreply.github.com>
Date: Fri, 4 Oct 2024 17:45:42 -0400
Subject: [PATCH] core: Extract `TransactionManager` from
 `clp::ffi::ir_stream::Deserializer`; Improve class' docs and require nothrow
 for its handlers. (#548)

Co-authored-by: kirkrodrigues <2454684+kirkrodrigues@users.noreply.github.com>
---
 components/core/CMakeLists.txt                |  1 +
 .../core/src/clp/TransactionManager.hpp       | 51 +++++++++++++++++++
 .../src/clp/ffi/ir_stream/Deserializer.cpp    | 49 ++----------------
 3 files changed, 55 insertions(+), 46 deletions(-)
 create mode 100644 components/core/src/clp/TransactionManager.hpp

diff --git a/components/core/CMakeLists.txt b/components/core/CMakeLists.txt
index 67eb80040..178f3e529 100644
--- a/components/core/CMakeLists.txt
+++ b/components/core/CMakeLists.txt
@@ -480,6 +480,7 @@ set(SOURCE_FILES_unitTest
         src/clp/TimestampPattern.cpp
         src/clp/TimestampPattern.hpp
         src/clp/TraceableException.hpp
+        src/clp/TransactionManager.hpp
         src/clp/type_utils.hpp
         src/clp/utf8_utils.cpp
         src/clp/utf8_utils.hpp
diff --git a/components/core/src/clp/TransactionManager.hpp b/components/core/src/clp/TransactionManager.hpp
new file mode 100644
index 000000000..fe70f5547
--- /dev/null
+++ b/components/core/src/clp/TransactionManager.hpp
@@ -0,0 +1,51 @@
+#ifndef CLP_TRANSACTIONMANAGER_HPP
+#define CLP_TRANSACTIONMANAGER_HPP
+
+#include <type_traits>
+
+namespace clp {
+/**
+ * A class that on destruction, performs different actions depending on whether a transaction
+ * succeeds or fails. The default state assumes the transaction fails.
+ * @tparam SuccessHandler A cleanup lambda to call on success.
+ * @tparam FailureHandler A cleanup lambda to call on failure.
+ */
+template <typename SuccessHandler, typename FailureHandler>
+requires(std::is_nothrow_invocable_v<SuccessHandler> && std::is_nothrow_invocable_v<FailureHandler>)
+class TransactionManager {
+public:
+    // Constructor
+    TransactionManager(SuccessHandler success_handler, FailureHandler failure_handler)
+            : m_success_handler{success_handler},
+              m_failure_handler{failure_handler} {}
+
+    // Delete copy/move constructor and assignment
+    TransactionManager(TransactionManager const&) = delete;
+    TransactionManager(TransactionManager&&) = delete;
+    auto operator=(TransactionManager const&) -> TransactionManager& = delete;
+    auto operator=(TransactionManager&&) -> TransactionManager& = delete;
+
+    // Destructor
+    ~TransactionManager() {
+        if (m_success) {
+            m_success_handler();
+        } else {
+            m_failure_handler();
+        }
+    }
+
+    // Methods
+    /**
+     * Marks the transaction as successful.
+     */
+    auto mark_success() -> void { m_success = true; }
+
+private:
+    // Variables
+    SuccessHandler m_success_handler;
+    FailureHandler m_failure_handler;
+    bool m_success{false};
+};
+}  // namespace clp
+
+#endif  // CLP_TRANSACTIONMANAGER_HPP
diff --git a/components/core/src/clp/ffi/ir_stream/Deserializer.cpp b/components/core/src/clp/ffi/ir_stream/Deserializer.cpp
index 11034c4a6..5402f9b98 100644
--- a/components/core/src/clp/ffi/ir_stream/Deserializer.cpp
+++ b/components/core/src/clp/ffi/ir_stream/Deserializer.cpp
@@ -5,7 +5,6 @@
 #include <string_view>
 #include <system_error>
 #include <tuple>
-#include <type_traits>
 #include <utility>
 #include <vector>
 
@@ -14,6 +13,7 @@
 
 #include "../../ReaderInterface.hpp"
 #include "../../time_types.hpp"
+#include "../../TransactionManager.hpp"
 #include "../KeyValuePairLogEvent.hpp"
 #include "decoding_methods.hpp"
 #include "ir_unit_deserialization_methods.hpp"
@@ -22,49 +22,6 @@
 
 namespace clp::ffi::ir_stream {
 namespace {
-/**
- * Class to perform different actions depending on whether a transaction succeeds or fails. The
- * default state assumes the transaction fails.
- * @tparam SuccessHandler A cleanup lambda to call on success.
- * @tparam FailureHandler A cleanup lambda to call on failure.
- */
-template <typename SuccessHandler, typename FailureHandler>
-requires(std::is_invocable_v<SuccessHandler> && std::is_invocable_v<FailureHandler>)
-class TransactionManager {
-public:
-    // Constructor
-    TransactionManager(SuccessHandler success_handler, FailureHandler failure_handler)
-            : m_success_handler{success_handler},
-              m_failure_handler{failure_handler} {}
-
-    // Delete copy/move constructor and assignment
-    TransactionManager(TransactionManager const&) = delete;
-    TransactionManager(TransactionManager&&) = delete;
-    auto operator=(TransactionManager const&) -> TransactionManager& = delete;
-    auto operator=(TransactionManager&&) -> TransactionManager& = delete;
-
-    // Destructor
-    ~TransactionManager() {
-        if (m_success) {
-            m_success_handler();
-        } else {
-            m_failure_handler();
-        }
-    }
-
-    // Methods
-    /**
-     * Marks the transaction as successful.
-     */
-    auto mark_success() -> void { m_success = true; }
-
-private:
-    // Variables
-    SuccessHandler m_success_handler;
-    FailureHandler m_failure_handler;
-    bool m_success{false};
-};
-
 /**
  * @param tag
  * @return Whether the tag represents a schema tree node.
@@ -122,8 +79,8 @@ auto Deserializer::deserialize_to_next_log_event(clp::ReaderInterface& reader
     auto const utc_offset_snapshot{m_utc_offset};
     m_schema_tree->take_snapshot();
     TransactionManager revert_manager{
-            []() -> void {},
-            [&]() -> void {
+            []() noexcept -> void {},
+            [&]() noexcept -> void {
                 m_utc_offset = utc_offset_snapshot;
                 m_schema_tree->revert();
             }