treewide: drop trivial leaf virtual inheritance

this does nothing on classes that are never used as base classes and
have only a single base class of their own. all of these classes are
also made final to prove that they are indeed in this category. once
we need to derive any of them we can erase their `final` specifiers.

Change-Id: I4bd8e50a58815227392b5a5a762fda4542d15bae

lix/libcmd/repl-interacter.hh

@@ -32,7 +32,7 @@ public:
     virtual ~ReplInteracter(){};
 };
 
-class ReadlineLikeInteracter : public virtual ReplInteracter
+class ReadlineLikeInteracter final : public ReplInteracter
 {
     std::string historyFile;
 public:
@@ -50,7 +50,7 @@ public:
     virtual ~ReadlineLikeInteracter() override;
 };
 
-class AutomationInteracter : public virtual ReplInteracter
+class AutomationInteracter final : public ReplInteracter
 {
 public:
     AutomationInteracter() = default;

lix/libstore/build/local-derivation-goal.cc

@@ -966,7 +966,7 @@ bool LocalDerivationGoal::isAllowed(const DerivedPath & req)
 }
 
 
-struct RestrictedStoreConfig : virtual LocalFSStoreConfig
+struct RestrictedStoreConfig final : LocalFSStoreConfig
 {
     using LocalFSStoreConfig::LocalFSStoreConfig;
     const std::string name() override { return "Restricted Store"; }

lix/libstore/dummy-store.cc

@@ -3,7 +3,7 @@
 
 namespace nix {
 
-struct DummyStoreConfig : virtual StoreConfig {
+struct DummyStoreConfig final : StoreConfig {
     using StoreConfig::StoreConfig;
 
     const std::string name() override { return "Dummy Store"; }
@@ -16,7 +16,7 @@ struct DummyStoreConfig : virtual StoreConfig {
     }
 };
 
-struct DummyStore : public virtual Store
+struct DummyStore final : public Store
 {
     DummyStoreConfig config_;
 

lix/libstore/http-binary-cache-store.cc

@@ -8,7 +8,7 @@ namespace nix {
 
 MakeError(UploadToHTTP, Error);
 
-struct HttpBinaryCacheStoreConfig : virtual BinaryCacheStoreConfig
+struct HttpBinaryCacheStoreConfig final : BinaryCacheStoreConfig
 {
     using BinaryCacheStoreConfig::BinaryCacheStoreConfig;
 
@@ -22,7 +22,7 @@ struct HttpBinaryCacheStoreConfig : virtual BinaryCacheStoreConfig
     }
 };
 
-class HttpBinaryCacheStore : public virtual BinaryCacheStore
+class HttpBinaryCacheStore final : public BinaryCacheStore
 {
 private:
 

lix/libstore/legacy-ssh-store.cc

@@ -44,7 +44,7 @@ struct LegacySSHStoreConfigWithLog : LegacySSHStoreConfig
     const Setting<int> logFD{this, -1, "log-fd", "file descriptor to which SSH's stderr is connected"};
 };
 
-struct LegacySSHStore : public virtual Store
+struct LegacySSHStore final : public Store
 {
     LegacySSHStoreConfigWithLog config_;
 

lix/libstore/local-binary-cache-store.cc

@@ -7,7 +7,7 @@
 
 namespace nix {
 
-struct LocalBinaryCacheStoreConfig : virtual BinaryCacheStoreConfig
+struct LocalBinaryCacheStoreConfig final : BinaryCacheStoreConfig
 {
     using BinaryCacheStoreConfig::BinaryCacheStoreConfig;
 
@@ -21,7 +21,7 @@ struct LocalBinaryCacheStoreConfig : virtual BinaryCacheStoreConfig
     }
 };
 
-class LocalBinaryCacheStore : public virtual BinaryCacheStore
+class LocalBinaryCacheStore final : public BinaryCacheStore
 {
 private:
 

lix/libstore/local-store.hh

@@ -37,7 +37,7 @@ struct OptimiseStats
     uint64_t blocksFreed = 0;
 };
 
-struct LocalStoreConfig : virtual LocalFSStoreConfig
+struct LocalStoreConfig final : LocalFSStoreConfig
 {
     using LocalFSStoreConfig::LocalFSStoreConfig;
 

lix/libstore/s3-binary-cache-store.cc

@@ -184,7 +184,7 @@ S3Helper::FileTransferResult S3Helper::getObject(
     return res;
 }
 
-struct S3BinaryCacheStoreConfig : virtual BinaryCacheStoreConfig
+struct S3BinaryCacheStoreConfig final : BinaryCacheStoreConfig
 {
     using BinaryCacheStoreConfig::BinaryCacheStoreConfig;
 

lix/libstore/ssh-store.cc

@@ -27,7 +27,7 @@ struct SSHStoreConfig : virtual RemoteStoreConfig, virtual CommonSSHStoreConfig
     }
 };
 
-class SSHStore : public virtual RemoteStore
+class SSHStore final : public RemoteStore
 {
     SSHStoreConfig config_;
 

lix/nix/config.cc

@@ -7,7 +7,7 @@
 
 using namespace nix;
 
-struct CmdConfig : virtual MultiCommand
+struct CmdConfig final : MultiCommand
 {
     CmdConfig() : MultiCommand(RegisterCommand::getCommandsFor({"config"}))
     { }

lix/nix/derivation.cc

@@ -2,7 +2,7 @@
 
 using namespace nix;
 
-struct CmdDerivation : virtual MultiCommand
+struct CmdDerivation final : MultiCommand
 {
     CmdDerivation() : MultiCommand(RegisterCommand::getCommandsFor({"derivation"}))
     { }

lix/nix/realisation.cc

@@ -5,7 +5,7 @@
 
 using namespace nix;
 
-struct CmdRealisation : virtual MultiCommand
+struct CmdRealisation final : MultiCommand
 {
     CmdRealisation() : MultiCommand(RegisterCommand::getCommandsFor({"realisation"}))
     { }

lix/nix/registry.cc

@@ -204,7 +204,7 @@ struct CmdRegistryPin : RegistryCommand, EvalCommand
     }
 };
 
-struct CmdRegistry : virtual MultiCommand
+struct CmdRegistry final : MultiCommand
 {
     CmdRegistry()
         : MultiCommand({

lix/nix/store.cc

@@ -2,7 +2,7 @@
 
 using namespace nix;
 
-struct CmdStore : virtual MultiCommand
+struct CmdStore final : MultiCommand
 {
     CmdStore() : MultiCommand(RegisterCommand::getCommandsFor({"store"}))
     { }