Add missing const.

38 files changed, 72 insertions, 65 deletions

diff --git a/src/actormanager.h b/src/actormanager.h
index f7e306b2a..df5d7ab38 100644
--- a/src/actormanager.h
+++ b/src/actormanager.h
@@ -251,10 +251,10 @@ class ActorManager final: public ConfigListener
 
         void addIgnorePickupItem(const std::string &name);
 
-        void setPriorityAttackMobs(std::list<std::string> mobs)
+        void setPriorityAttackMobs(const std::list<std::string> &mobs)
         { mPriorityAttackMobs = mobs; }
 
-        void setAttackMobs(std::list<std::string> mobs)
+        void setAttackMobs(const std::list<std::string> &mobs)
         { mAttackMobs = mobs; }
 
         int getPriorityAttackMobsSize() const A_WARN_UNUSED
diff --git a/src/animationdelayload.h b/src/animationdelayload.h
index 1fd4731ef..6b5216a64 100644
--- a/src/animationdelayload.h
+++ b/src/animationdelayload.h
@@ -41,7 +41,7 @@ class AnimationDelayLoad final
 
         void load();
 
-        void setAction(std::string action)
+        void setAction(const std::string &action)
         { mAction = action; }
 
     private:
diff --git a/src/avatar.h b/src/avatar.h
index 03050a06f..60e68a948 100644
--- a/src/avatar.h
+++ b/src/avatar.h
@@ -115,7 +115,7 @@ public:
     std::string getMap() const A_WARN_UNUSED
     { return mMap; }
 
-    void setMap(std::string map)
+    void setMap(const std::string &map)
     { mMap = map; }
 
     int getX() const A_WARN_UNUSED
@@ -169,7 +169,7 @@ public:
     const std::string &getIp() const A_WARN_UNUSED
     { return mIp; }
 
-    void setIp(std::string ip)
+    void setIp(const std::string &ip)
     { mIp = ip; }
 
     bool getPoison() const A_WARN_UNUSED
diff --git a/src/being/actorsprite.cpp b/src/being/actorsprite.cpp
index 29fa1290c..75d337bd5 100644
--- a/src/being/actorsprite.cpp
+++ b/src/being/actorsprite.cpp
@@ -208,7 +208,7 @@ void ActorSprite::updateStatusEffect(const int index, const bool newStatus)
     handleStatusEffect(effect, index);
 }
 
-void ActorSprite::handleStatusEffect(StatusEffect *const effect,
+void ActorSprite::handleStatusEffect(const StatusEffect *const effect,
                                      const int effectId)
 {
     if (!effect)
diff --git a/src/being/actorsprite.h b/src/being/actorsprite.h
index 76e90182d..fd90aba09 100644
--- a/src/being/actorsprite.h
+++ b/src/being/actorsprite.h
@@ -210,7 +210,7 @@ protected:
      * \param The StatusEffect to effect
      * \param effectId -1 for stun, otherwise the effect index
      */
-    virtual void handleStatusEffect(StatusEffect *const effect,
+    virtual void handleStatusEffect(const StatusEffect *const effect,
                                     const int effectId);
 
     void setupSpriteDisplay(const SpriteDisplay &display,
diff --git a/src/being/being.h b/src/being/being.h
index 793454ca2..2a6ec9195 100644
--- a/src/being/being.h
+++ b/src/being/being.h
@@ -474,7 +474,7 @@ class Being : public ActorSprite, public ConfigListener
         /**
          * Sets the walk speed in pixels per second.
          */
-        void setWalkSpeed(Vector speed)
+        void setWalkSpeed(const Vector &speed)
         { mWalkSpeed = speed; mSpeed = speed.x; }
 
         /**
@@ -725,7 +725,7 @@ class Being : public ActorSprite, public ConfigListener
         const std::string &getIp() const A_WARN_UNUSED
         { return mIp; }
 
-        void setIp(std::string ip)
+        void setIp(const std::string &ip)
         { mIp = ip; }
 
         unsigned int getPvpRank() const A_WARN_UNUSED
@@ -791,7 +791,7 @@ class Being : public ActorSprite, public ConfigListener
         const std::string getComment() const A_WARN_UNUSED
         { return mComment; }
 
-        void setComment(std::string n)
+        void setComment(const std::string &n)
         { mComment = n; }
 
         static void clearCache();
@@ -829,7 +829,7 @@ class Being : public ActorSprite, public ConfigListener
 
         void updatePercentHP();
 
-        void setRaceName(std::string name)
+        void setRaceName(const std::string &name)
         { mRaceName = name; }
 
         std::string getRaceName() const A_WARN_UNUSED
diff --git a/src/being/beingcacheentry.h b/src/being/beingcacheentry.h
index af60a9090..c2c9aa513 100644
--- a/src/being/beingcacheentry.h
+++ b/src/being/beingcacheentry.h
@@ -97,7 +97,7 @@ class BeingCacheEntry final
         std::string getIp() const
         { return mIp; }
 
-        void setIp(std::string ip)
+        void setIp(const std::string &ip)
         { mIp = ip; }
 
         bool isAdvanced() const
diff --git a/src/client.cpp b/src/client.cpp
index ce4cd081b..83147d34c 100644
--- a/src/client.cpp
+++ b/src/client.cpp
@@ -2053,7 +2053,7 @@ void Client::initConfigDir()
  * Initializes the home directory. On UNIX and FreeBSD, ~/.mana is used. On
  * Windows and other systems we use the current working directory.
  */
-void Client::initServerConfig(std::string serverName)
+void Client::initServerConfig(const std::string &serverName)
 {
     mServerConfigDir = mConfigDir + dirSeparator + serverName;
 
diff --git a/src/client.h b/src/client.h
index 0d7749e3f..7d83cf789 100644
--- a/src/client.h
+++ b/src/client.h
@@ -368,7 +368,7 @@ private:
 
     void initScreenshotDir();
 
-    void initServerConfig(std::string serverName);
+    void initServerConfig(const std::string &serverName);
 
     static void initFeatures();
 
diff --git a/src/gui/widgets/button.h b/src/gui/widgets/button.h
index 015faf009..716ed7728 100644
--- a/src/gui/widgets/button.h
+++ b/src/gui/widgets/button.h
@@ -158,7 +158,7 @@ class Button final : public Widget,
 
         void mouseReleased(MouseEvent& event) override final;
 
-        void setDescription(std::string text)
+        void setDescription(const std::string &text)
         { mDescription = text; }
 
         std::string getDescription() const A_WARN_UNUSED
diff --git a/src/gui/windows/socialwindow.cpp b/src/gui/windows/socialwindow.cpp
index 6a17514d6..4e22595a6 100644
--- a/src/gui/windows/socialwindow.cpp
+++ b/src/gui/windows/socialwindow.cpp
@@ -588,7 +588,7 @@ public:
             being->setDamageTaken(0);
     }
 
-    Avatar* findAvatarbyName(std::string name)
+    Avatar* findAvatarbyName(const std::string &name)
     {
         std::vector<Avatar*> *const avatars = mBeings->getMembers();
         if (!avatars)
diff --git a/src/gui/windows/statuswindow.cpp b/src/gui/windows/statuswindow.cpp
index f2473241c..a45c206f5 100644
--- a/src/gui/windows/statuswindow.cpp
+++ b/src/gui/windows/statuswindow.cpp
@@ -706,7 +706,7 @@ std::string StatusWindow::translateLetter(const char *const letters)
     return std::string(buf);
 }
 
-std::string StatusWindow::translateLetter2(std::string letters)
+std::string StatusWindow::translateLetter2(const std::string &letters)
 {
     if (letters.size() < 5)
         return "";
diff --git a/src/gui/windows/statuswindow.h b/src/gui/windows/statuswindow.h
index 797e7647f..2beeea586 100644
--- a/src/gui/windows/statuswindow.h
+++ b/src/gui/windows/statuswindow.h
@@ -95,7 +95,7 @@ class StatusWindow final : public Window,
 
     private:
         static std::string translateLetter(const char *const letters);
-        static std::string translateLetter2(std::string letters);
+        static std::string translateLetter2(const std::string &letters);
 
         /**
          * Status Part
diff --git a/src/maplayer.cpp b/src/maplayer.cpp
index 2db140d67..7db90b956 100644
--- a/src/maplayer.cpp
+++ b/src/maplayer.cpp
@@ -850,7 +850,7 @@ ObjectsLayer::~ObjectsLayer()
     mTiles = nullptr;
 }
 
-void ObjectsLayer::addObject(std::string name, const int type,
+void ObjectsLayer::addObject(const std::string &name, const int type,
                              const unsigned x, const unsigned y,
                              unsigned dx, unsigned dy)
 {
diff --git a/src/maplayer.h b/src/maplayer.h
index 88db82214..ad2378010 100644
--- a/src/maplayer.h
+++ b/src/maplayer.h
@@ -283,13 +283,13 @@ class MapItem final
         const std::string &getComment() const A_WARN_UNUSED
         { return mComment; }
 
-        void setComment(std::string comment)
+        void setComment(const std::string &comment)
         { mComment = comment; }
 
         const std::string &getName() const A_WARN_UNUSED
         { return mName; }
 
-        void setName(std::string name)
+        void setName(const std::string &name)
         { mName = name; }
 
         void draw(Graphics *const graphics, const int x, const int y,
@@ -313,7 +313,7 @@ class ObjectsLayer final
 
         ~ObjectsLayer();
 
-        void addObject(std::string name, const int type,
+        void addObject(const std::string &name, const int type,
                        const unsigned x, const unsigned y,
                        unsigned dx, unsigned dy);
 
diff --git a/src/net/ea/network.cpp b/src/net/ea/network.cpp
index 128ca2996..61a9499d0 100644
--- a/src/net/ea/network.cpp
+++ b/src/net/ea/network.cpp
@@ -86,7 +86,7 @@ Network::~Network()
     TcpNet::quit();
 }
 
-bool Network::connect(ServerInfo server)
+bool Network::connect(const ServerInfo &server)
 {
     if (mState != IDLE && mState != NET_ERROR)
     {
diff --git a/src/net/ea/network.h b/src/net/ea/network.h
index 08f9d7c71..57102d7e3 100644
--- a/src/net/ea/network.h
+++ b/src/net/ea/network.h
@@ -42,7 +42,7 @@ class Network
 
         virtual ~Network();
 
-        bool connect(ServerInfo server);
+        bool connect(const ServerInfo &server);
 
         void disconnect();
 
diff --git a/src/render/graphics.cpp b/src/render/graphics.cpp
index 5437e6737..24c3ab69e 100644
--- a/src/render/graphics.cpp
+++ b/src/render/graphics.cpp
@@ -547,7 +547,7 @@ void Graphics::setWindowSize(const int width A_UNUSED,
 #endif
 }
 
-bool Graphics::pushClipArea(Rect area)
+bool Graphics::pushClipArea(const Rect &area)
 {
     // Ignore area with a negate width or height
     // by simple pushing an empty clip area
diff --git a/src/render/graphics.h b/src/render/graphics.h
index 541bb789d..ce612193c 100644
--- a/src/render/graphics.h
+++ b/src/render/graphics.h
@@ -419,7 +419,7 @@ class Graphics
          * @return False if the the new area lays outside the current clip 
          *         area.
          */
-        virtual bool pushClipArea(Rect area);
+        virtual bool pushClipArea(const Rect &area);
 
         /**
          * Removes the top most clip area from the stack.
diff --git a/src/render/graphicsdef.hpp b/src/render/graphicsdef.hpp
index b11f88249..29cdc4a0f 100644
--- a/src/render/graphicsdef.hpp
+++ b/src/render/graphicsdef.hpp
@@ -37,7 +37,7 @@ public:
 
     void endDraw();
 
-    bool pushClipArea(Rect area) override final;
+    bool pushClipArea(const Rect &area) override final;
 
     void popClipArea() override final;
 
diff --git a/src/render/mobileopenglgraphics.cpp b/src/render/mobileopenglgraphics.cpp
index 3db76a616..65b6b291a 100644
--- a/src/render/mobileopenglgraphics.cpp
+++ b/src/render/mobileopenglgraphics.cpp
@@ -961,7 +961,7 @@ SDL_Surface* MobileOpenGLGraphics::getScreenshot()
     return screenshot;
 }
 
-bool MobileOpenGLGraphics::pushClipArea(Rect area)
+bool MobileOpenGLGraphics::pushClipArea(const Rect &area)
 {
     int transX = 0;
     int transY = 0;
diff --git a/src/render/normalopenglgraphics.cpp b/src/render/normalopenglgraphics.cpp
index 8f3659936..bb8eed230 100644
--- a/src/render/normalopenglgraphics.cpp
+++ b/src/render/normalopenglgraphics.cpp
@@ -1223,7 +1223,7 @@ SDL_Surface* NormalOpenGLGraphics::getScreenshot()
     return screenshot;
 }
 
-bool NormalOpenGLGraphics::pushClipArea(Rect area)
+bool NormalOpenGLGraphics::pushClipArea(const Rect &area)
 {
     int transX = 0;
     int transY = 0;
diff --git a/src/render/nullopenglgraphics.cpp b/src/render/nullopenglgraphics.cpp
index 919b43c10..6497a7b5a 100644
--- a/src/render/nullopenglgraphics.cpp
+++ b/src/render/nullopenglgraphics.cpp
@@ -938,7 +938,7 @@ SDL_Surface* NullOpenGLGraphics::getScreenshot()
     return nullptr;
 }
 
-bool NullOpenGLGraphics::pushClipArea(Rect area)
+bool NullOpenGLGraphics::pushClipArea(const Rect &area)
 {
     int transX = 0;
     int transY = 0;
diff --git a/src/render/safeopenglgraphics.cpp b/src/render/safeopenglgraphics.cpp
index 177cfecb5..d5c9981a3 100644
--- a/src/render/safeopenglgraphics.cpp
+++ b/src/render/safeopenglgraphics.cpp
@@ -529,7 +529,7 @@ SDL_Surface* SafeOpenGLGraphics::getScreenshot()
     return screenshot;
 }
 
-bool SafeOpenGLGraphics::pushClipArea(Rect area)
+bool SafeOpenGLGraphics::pushClipArea(const Rect &area)
 {
     int transX = 0;
     int transY = 0;
diff --git a/src/render/sdl2graphics.cpp b/src/render/sdl2graphics.cpp
index 2b70a8ab0..25a689ddf 100644
--- a/src/render/sdl2graphics.cpp
+++ b/src/render/sdl2graphics.cpp
@@ -670,7 +670,7 @@ void SDLGraphics::endDraw()
     popClipArea();
 }
 
-bool SDLGraphics::pushClipArea(Rect area)
+bool SDLGraphics::pushClipArea(const Rect &area)
 {
     const bool result = Graphics::pushClipArea(area);
 
diff --git a/src/render/sdl2softwaregraphics.cpp b/src/render/sdl2softwaregraphics.cpp
index a176b6905..e5943f7c7 100644
--- a/src/render/sdl2softwaregraphics.cpp
+++ b/src/render/sdl2softwaregraphics.cpp
@@ -1125,7 +1125,7 @@ void SDL2SoftwareGraphics::endDraw()
     popClipArea();
 }
 
-bool SDL2SoftwareGraphics::pushClipArea(Rect area)
+bool SDL2SoftwareGraphics::pushClipArea(const Rect &area)
 {
     const bool result = Graphics::pushClipArea(area);
 
diff --git a/src/render/sdlgraphics.cpp b/src/render/sdlgraphics.cpp
index ac304b7ab..9b852689d 100644
--- a/src/render/sdlgraphics.cpp
+++ b/src/render/sdlgraphics.cpp
@@ -1122,7 +1122,7 @@ void SDLGraphics::endDraw()
     popClipArea();
 }
 
-bool SDLGraphics::pushClipArea(Rect area)
+bool SDLGraphics::pushClipArea(const Rect &area)
 {
     const bool result = Graphics::pushClipArea(area);
     const ClipRect &carea = mClipStack.top();
diff --git a/src/render/surfacegraphics.h b/src/render/surfacegraphics.h
index 44c2691ae..ab569acb0 100644
--- a/src/render/surfacegraphics.h
+++ b/src/render/surfacegraphics.h
@@ -63,7 +63,7 @@ class SurfaceGraphics final : public Graphics
         void endDraw() override final
         { }
 
-        bool pushClipArea(Rect rect A_UNUSED) override final
+        bool pushClipArea(const Rect &rect A_UNUSED) override final
         { return true; }
 
         void popClipArea() override final
diff --git a/src/resources/beinginfo.cpp b/src/resources/beinginfo.cpp
index 8b76d7e2a..d7ecb8136 100644
--- a/src/resources/beinginfo.cpp
+++ b/src/resources/beinginfo.cpp
@@ -155,9 +155,12 @@ const Attack *BeingInfo::getAttack(const int id) const
     return (i == mAttacks.end()) ? empty : (*i).second;
 }
 
-void BeingInfo::addAttack(const int id, std::string action,
-                          std::string skyAction, std::string waterAction,
-                          const int effectId, const int hitEffectId,
+void BeingInfo::addAttack(const int id,
+                          const std::string &action,
+                          const std::string &skyAction,
+                          const std::string &waterAction,
+                          const int effectId,
+                          const int hitEffectId,
                           const int criticalHitEffectId,
                           const int missEffectId,
                           const std::string &missileParticle)
diff --git a/src/resources/beinginfo.h b/src/resources/beinginfo.h
index 31725d218..81a1f749d 100644
--- a/src/resources/beinginfo.h
+++ b/src/resources/beinginfo.h
@@ -117,9 +117,13 @@ class BeingInfo final
         const SoundInfo &getSound(const ItemSoundEvent event)
                                   const A_WARN_UNUSED;
 
-        void addAttack(const int id, std::string action, std::string skyAttack,
-                       std::string waterAttack, const int effectId,
-                       const int hitEffectId, const int criticalHitEffectId,
+        void addAttack(const int id,
+                       const std::string &action,
+                       const std::string &skyAttack,
+                       const std::string &waterAttack,
+                       const int effectId,
+                       const int hitEffectId,
+                       const int criticalHitEffectId,
                        const int missEffectId,
                        const std::string &missileParticle);
 
diff --git a/src/test/testmain.cpp b/src/test/testmain.cpp
index fbd7588ef..cae4aa3b7 100644
--- a/src/test/testmain.cpp
+++ b/src/test/testmain.cpp
@@ -274,7 +274,7 @@ int TestMain::readValue(const int ver, int def)
     return def;
 }
 
-int TestMain::invokeTest(std::string test)
+int TestMain::invokeTest(const std::string &test)
 {
     mConfig.setValue("opengl", static_cast<int>(RENDER_SOFTWARE));
 
@@ -292,7 +292,7 @@ int TestMain::invokeTest4()
     return ret;
 }
 
-int TestMain::invokeSoftwareRenderTest(std::string test)
+int TestMain::invokeSoftwareRenderTest(const std::string &test)
 {
     mConfig.setValue("opengl", static_cast<int>(RENDER_SOFTWARE));
     mConfig.write();
@@ -301,7 +301,7 @@ int TestMain::invokeSoftwareRenderTest(std::string test)
     return ret;
 }
 
-int TestMain::invokeFastOpenGLRenderTest(std::string test)
+int TestMain::invokeFastOpenGLRenderTest(const std::string &test)
 {
     mConfig.setValue("opengl", static_cast<int>(RENDER_NORMAL_OPENGL));
     mConfig.write();
@@ -310,7 +310,7 @@ int TestMain::invokeFastOpenGLRenderTest(std::string test)
     return ret;
 }
 
-int TestMain::invokeFastOpenBatchTest(std::string test)
+int TestMain::invokeFastOpenBatchTest(const std::string &test)
 {
     mConfig.setValue("opengl", static_cast<int>(RENDER_NORMAL_OPENGL));
     mConfig.write();
@@ -319,7 +319,7 @@ int TestMain::invokeFastOpenBatchTest(std::string test)
     return ret;
 }
 
-int TestMain::invokeSafeOpenGLRenderTest(std::string test)
+int TestMain::invokeSafeOpenGLRenderTest(const std::string &test)
 {
     mConfig.setValue("opengl", static_cast<int>(RENDER_SAFE_OPENGL));
     mConfig.write();
diff --git a/src/test/testmain.h b/src/test/testmain.h
index c46e6a1fc..72411417e 100644
--- a/src/test/testmain.h
+++ b/src/test/testmain.h
@@ -50,7 +50,7 @@ class TestMain final
     private:
         void initConfig();
 
-        int invokeTest(std::string test);
+        int invokeTest(const std::string &test);
 
         int invokeTest3();
 
@@ -58,13 +58,13 @@ class TestMain final
 
         int invokeTest7();
 
-        int invokeSoftwareRenderTest(std::string test);
+        int invokeSoftwareRenderTest(const std::string &test);
 
-        int invokeFastOpenGLRenderTest(std::string test);
+        int invokeFastOpenGLRenderTest(const std::string &test);
 
-        int invokeFastOpenBatchTest(std::string test);
+        int invokeFastOpenBatchTest(const std::string &test);
 
-        int invokeSafeOpenGLRenderTest(std::string test);
+        int invokeSafeOpenGLRenderTest(const std::string &test);
 
         void testsMain();
 
diff --git a/src/textcommand.h b/src/textcommand.h
index 2011e90c2..9c807badc 100644
--- a/src/textcommand.h
+++ b/src/textcommand.h
@@ -125,13 +125,13 @@ class TextCommand final
         TextCommandType getCommandType() const A_WARN_UNUSED
         { return mCommandType; }
 
-        void setCommand(std::string command)
+        void setCommand(const std::string &command)
         { mCommand = command; }
 
-        void setComment(std::string comment)
+        void setComment(const std::string &comment)
         { mComment = comment; }
 
-        void setSymbol(std::string symbol)
+        void setSymbol(const std::string &symbol)
         { mSymbol = symbol; }
 
         void setId(const unsigned int id)
@@ -140,7 +140,7 @@ class TextCommand final
         void setTargetType(const SpellTarget targetType)
         { mTargetType = targetType; }
 
-        void setIcon(std::string icon)
+        void setIcon(const std::string &icon)
         { mIcon = icon; loadImage(); }
 
         void setMana(const unsigned int mana)
diff --git a/src/tileset.h b/src/tileset.h
index 77140544e..05508658a 100644
--- a/src/tileset.h
+++ b/src/tileset.h
@@ -55,7 +55,7 @@ class Tileset final : public ImageSet
         /**
          * Set tileset property.
          */
-        void setProperties(std::map<std::string, std::string> props)
+        void setProperties(const std::map<std::string, std::string> &props)
         { mProperties = props; }
 
         /**
diff --git a/src/utils/stringutils.cpp b/src/utils/stringutils.cpp
index f47f724a8..e7b850510 100644
--- a/src/utils/stringutils.cpp
+++ b/src/utils/stringutils.cpp
@@ -283,7 +283,7 @@ std::string removeSpriteIndex(std::string str)
     return str;
 }
 
-const char* getSafeUtf8String(std::string text)
+const char* getSafeUtf8String(const std::string &text)
 {
     const size_t sz = text.size();
     const size_t size = sz + UTF8_MAX_SIZE;
diff --git a/src/utils/stringutils.h b/src/utils/stringutils.h
index 7cf924d98..cd04006ef 100644
--- a/src/utils/stringutils.h
+++ b/src/utils/stringutils.h
@@ -149,7 +149,7 @@ std::string extractNameFromSprite(std::string str) A_WARN_UNUSED;
 
 std::string removeSpriteIndex(std::string str) A_WARN_UNUSED;
 
-const char* getSafeUtf8String(std::string text) A_WARN_UNUSED;
+const char* getSafeUtf8String(const std::string &text) A_WARN_UNUSED;
 
 void getSafeUtf8String(std::string text, char *const buf);
 
diff --git a/src/utils/translation/poparser.cpp b/src/utils/translation/poparser.cpp
index c105bf0da..bcb577f84 100644
--- a/src/utils/translation/poparser.cpp
+++ b/src/utils/translation/poparser.cpp
@@ -42,7 +42,7 @@ PoParser::PoParser() :
 {
 }
 
-void PoParser::openFile(std::string name)
+void PoParser::openFile(const std::string &name)
 {
     const ResourceManager *const resman = ResourceManager::getInstance();
     if (!resman)
@@ -228,14 +228,14 @@ PoDict *PoParser::getEmptyDict()
     return new PoDict("");
 }
 
-bool PoParser::checkLang(std::string lang)
+bool PoParser::checkLang(const std::string &lang)
 {
     // check is po file exists
     const ResourceManager *const resman = ResourceManager::getInstance();
     return resman->exists(getFileName(lang));
 }
 
-std::string PoParser::getFileName(std::string lang)
+std::string PoParser::getFileName(const std::string &lang)
 {
     // get po file name from lang name
 //    logger->log("getFileName: translations/%s.po", lang.c_str());
diff --git a/src/utils/translation/poparser.h b/src/utils/translation/poparser.h
index 41598442b..d57dde061 100644
--- a/src/utils/translation/poparser.h
+++ b/src/utils/translation/poparser.h
@@ -39,15 +39,15 @@ class PoParser final
                      const std::string &restrict fileName = "",
                      PoDict *restrict const dict = nullptr);
 
-        static bool checkLang(std::string lang);
+        static bool checkLang(const std::string &lang);
 
         static PoDict *getEmptyDict();
 
     private:
-        void setLang(std::string lang)
+        void setLang(const std::string &lang)
         { mLang = lang; }
 
-        void openFile(std::string name);
+        void openFile(const std::string &name);
 
         bool readLine();
 
@@ -57,7 +57,7 @@ class PoParser final
 
         bool checkLine() const;
 
-        static std::string getFileName(std::string lang);
+        static std::string getFileName(const std::string &lang);
 
         PoDict *getDict() const;