refactor(3p/nix): Apply clang-tidy's modernize-* fixes r/787

This applies the modernization fixes listed here:

https://clang.llvm.org/extra/clang-tidy/checks/list.html

The 'modernize-use-trailing-return-type' fix was excluded due to my
personal preference (more specifically, I think the 'auto' keyword is
misleading in that position).

1 files changed, 6 insertions, 3 deletions

diff --git a/third_party/nix/src/nix/command.cc b/third_party/nix/src/nix/command.cc
index b35fb1be9898..b0efcb823dd6 100644
--- a/third_party/nix/src/nix/command.cc
+++ b/third_party/nix/src/nix/command.cc
@@ -1,11 +1,13 @@
 #include "command.hh"
 
+#include <utility>
+
 #include "derivations.hh"
 #include "store-api.hh"
 
 namespace nix {
 
-Commands* RegisterCommand::commands = 0;
+Commands* RegisterCommand::commands = nullptr;
 
 void Command::printHelp(const string& programName, std::ostream& out) {
   Args::printHelp(programName, out);
@@ -22,7 +24,8 @@ void Command::printHelp(const string& programName, std::ostream& out) {
   }
 }
 
-MultiCommand::MultiCommand(const Commands& _commands) : commands(_commands) {
+MultiCommand::MultiCommand(Commands _commands)
+    : commands(std::move(_commands)) {
   expectedArgs.push_back(ExpectedArg{
       "command", 1, true, [=](std::vector<std::string> ss) {
         assert(!command);
@@ -82,7 +85,7 @@ bool MultiCommand::processArgs(const Strings& args, bool finish) {
   }
 }
 
-StoreCommand::StoreCommand() {}
+StoreCommand::StoreCommand() = default;
 
 ref<Store> StoreCommand::getStore() {
   if (!_store) {