Cheats: Simplify code merging on import

The save file already does replacement.

src/core/cheats.cpp

@@ -581,7 +581,7 @@ std::string Cheats::FormatCodeForFile(const CodeInfo& code)
     fmt::format_to(appender, "OptionRange = {}:{}\n", code.option_range_start, code.option_range_end);
   }
 
-  fmt::format_to(appender, "{}\n", code.body);
+  fmt::format_to(appender, "{}\n\n", code.body, code.body.ends_with('\n') ? "\n" : "");
   return std::string(buf.begin(), buf.end());
 }
 
@@ -700,18 +700,6 @@ bool Cheats::SaveCodesToFile(const char* path, const CodeInfoList& codes, Error*
   return true;
 }
 
-void Cheats::MergeCheatList(CodeInfoList* dst, CodeInfoList src)
-{
-  for (CodeInfo& code : src)
-  {
-    CodeInfo* existing_code = FindCodeInInfoList(*dst, code.name);
-    if (existing_code)
-      *existing_code = std::move(code);
-    else
-      dst->push_back(std::move(code));
-  }
-}
-
 std::string Cheats::GetChtFilename(const std::string_view serial, std::optional<GameHash> hash, bool cheats)
 {
   return Path::Combine(cheats ? EmuFolders::Cheats : EmuFolders::Patches, GetChtTemplate(serial, hash, false));

src/core/cheats.h

@@ -116,9 +116,6 @@ extern bool UpdateCodeInFile(const char* path, const std::string_view name, cons
 /// Updates or adds multiple codes to the file, rewriting it.
 extern bool SaveCodesToFile(const char* path, const CodeInfoList& codes, Error* error);
 
-/// Merges two cheat lists, with any duplicates in the new list taking precedence.
-extern void MergeCheatList(CodeInfoList* dst, CodeInfoList src);
-
 /// Returns the path to a new cheat/patch cht for the specified serial and hash.
 extern std::string GetChtFilename(const std::string_view serial, std::optional<GameHash> hash, bool cheats);
 

src/duckstation-qt/gamecheatsettingswidget.cpp

@@ -488,8 +488,7 @@ void GameCheatSettingsWidget::importCodes(const std::string& file_contents)
     return;
   }
 
-  Cheats::MergeCheatList(&m_codes, std::move(new_codes));
-  if (!Cheats::SaveCodesToFile(getPathForSavingCheats().c_str(), m_codes, &error))
+  if (!Cheats::SaveCodesToFile(getPathForSavingCheats().c_str(), new_codes, &error))
   {
     QMessageBox::critical(this, tr("Error"),
                           tr("Failed to save file:\n%1").arg(QString::fromStdString(error.GetDescription())));