Avoid recalculating string-literal size on root tracker construction

This is a tiiiiiiny performance optimization, but it's free.

src/catch2/internal/catch_test_case_tracker.cpp

@@ -31,9 +31,27 @@ namespace TestCaseTracking {
 
     ITracker::~ITracker() = default;
 
+    void ITracker::addChild( ITrackerPtr const& child ) {
+        m_children.push_back( child );
+    }
+
+    ITrackerPtr ITracker::findChild( NameAndLocation const& nameAndLocation ) {
+        auto it = std::find_if(
+            m_children.begin(),
+            m_children.end(),
+            [&nameAndLocation]( ITrackerPtr const& tracker ) {
+                return tracker->nameAndLocation().location ==
+                           nameAndLocation.location &&
+                       tracker->nameAndLocation().name == nameAndLocation.name;
+            } );
+        return ( it != m_children.end() ) ? *it : nullptr;
+    }
+
+
 
     ITracker& TrackerContext::startRun() {
-        m_rootTracker = std::make_shared<SectionTracker>( NameAndLocation( "{root}", CATCH_INTERNAL_LINEINFO ), *this, nullptr );
+        using namespace std::string_literals;
+        m_rootTracker = std::make_shared<SectionTracker>( NameAndLocation( "{root}"s, CATCH_INTERNAL_LINEINFO ), *this, nullptr );
         m_currentTracker = nullptr;
         m_runState = Executing;
         return *m_rootTracker;
@@ -79,26 +97,7 @@ namespace TestCaseTracking {
     bool TrackerBase::isOpen() const {
         return m_runState != NotStarted && !isComplete();
     }
-    bool TrackerBase::hasChildren() const {
-        return !m_children.empty();
-    }
 
-
-    void TrackerBase::addChild( ITrackerPtr const& child ) {
-        m_children.push_back( child );
-    }
-
-    ITrackerPtr TrackerBase::findChild( NameAndLocation const& nameAndLocation ) {
-        auto it = std::find_if( m_children.begin(), m_children.end(),
-            [&nameAndLocation]( ITrackerPtr const& tracker ){
-                return
-                    tracker->nameAndLocation().location == nameAndLocation.location &&
-                    tracker->nameAndLocation().name == nameAndLocation.name;
-            } );
-        return( it != m_children.end() )
-            ? *it
-            : nullptr;
-    }
     ITracker& TrackerBase::parent() {
         assert( m_parent ); // Should always be non-null except for root
         return *m_parent;

src/catch2/internal/catch_test_case_tracker.hpp

@@ -36,6 +36,11 @@ namespace TestCaseTracking {
     class  ITracker {
         NameAndLocation m_nameAndLocation;
 
+        using Children = std::vector<ITrackerPtr>;
+
+    protected:
+        Children m_children;
+
     public:
         ITracker(NameAndLocation const& nameAndLoc) :
             m_nameAndLocation(nameAndLoc)
@@ -54,7 +59,6 @@ namespace TestCaseTracking {
         virtual bool isComplete() const = 0; // Successfully completed or failed
         virtual bool isSuccessfullyCompleted() const = 0;
         virtual bool isOpen() const = 0; // Started but not complete
-        virtual bool hasChildren() const = 0;
         virtual bool hasStarted() const = 0;
 
         virtual ITracker& parent() = 0;
@@ -64,8 +68,20 @@ namespace TestCaseTracking {
         virtual void fail() = 0;
         virtual void markAsNeedingAnotherRun() = 0;
 
-        virtual void addChild( ITrackerPtr const& child ) = 0;
-        virtual ITrackerPtr findChild( NameAndLocation const& nameAndLocation ) = 0;
+        //! Register a nested ITracker
+        void addChild( ITrackerPtr const& child );
+        /**
+         * Returns ptr to specific child if register with this tracker.
+         *
+         * Returns nullptr if not found.
+         */
+        ITrackerPtr findChild( NameAndLocation const& nameAndLocation );
+        //! Have any children been added?
+        bool hasChildren() const {
+            return !m_children.empty();
+        }
+
+
         virtual void openChild() = 0;
 
         // Debug/ checking
@@ -109,10 +125,8 @@ namespace TestCaseTracking {
             Failed
         };
 
-        using Children = std::vector<ITrackerPtr>;
         TrackerContext& m_ctx;
         ITracker* m_parent;
-        Children m_children;
         CycleState m_runState = NotStarted;
 
     public:
@@ -121,14 +135,10 @@ namespace TestCaseTracking {
         bool isComplete() const override;
         bool isSuccessfullyCompleted() const override;
         bool isOpen() const override;
-        bool hasChildren() const override;
         bool hasStarted() const override {
             return m_runState != NotStarted;
         }
 
-        void addChild( ITrackerPtr const& child ) override;
-
-        ITrackerPtr findChild( NameAndLocation const& nameAndLocation ) override;
         ITracker& parent() override;
 
         void openChild() override;