Make /world the default path for DD4hep conditions when no ':' appears in the name

Det/LbDD4hep/include/LbDD4hep/ConditionAccessorHolder.h

@@ -108,12 +108,15 @@ namespace LHCb::Det::LbDD4hep {
   protected:
     dd4hep::Condition::key_type getKey() const {
       const auto colonPos = m_key.value().find_first_of( ':' );
-      if ( colonPos == std::string::npos ) {
-        throw std::runtime_error( "Expected a ':' in condition key " + m_key.value() );
+      if ( colonPos != std::string::npos ) {
+        auto                           path = m_key.value().substr( 0, colonPos );
+        auto                           hash = dd4hep::ConditionKey::itemCode( m_key.value().substr( colonPos + 1 ) );
+        dd4hep::ConditionKey::KeyMaker m( dd4hep::detail::hash32( path ), hash );
+        return m.hash;
       }
-      auto                           path = m_key.value().substr( 0, colonPos );
-      auto                           hash = dd4hep::ConditionKey::itemCode( m_key.value().substr( colonPos + 1 ) );
-      dd4hep::ConditionKey::KeyMaker m( dd4hep::detail::hash32( path ), hash );
+      // otherwise default path is "/world"
+      dd4hep::ConditionKey::KeyMaker m( dd4hep::detail::hash32( "/world" ),
+                                        dd4hep::ConditionKey::itemCode( m_key.value() ) );
       return m.hash;
     }
 

Det/LbDD4hep/src/DD4hepSvc.cpp

@@ -44,8 +44,13 @@ namespace {
    */
   dd4hep::Condition::key_type makeKey( std::string const& s ) {
     auto colonPos = s.find_first_of( ':' );
-    auto hi       = dd4hep::ConditionKey::itemCode( s.substr( 0, colonPos ) );
-    auto low      = dd4hep::ConditionKey::itemCode( colonPos == std::string::npos ? "" : s.substr( colonPos + 1 ) );
+    if ( colonPos != std::string::npos ) {
+      auto hi  = dd4hep::ConditionKey::itemCode( s.substr( 0, colonPos ) );
+      auto low = dd4hep::ConditionKey::itemCode( s.substr( colonPos + 1 ) );
+      return ( ( (dd4hep::Condition::key_type)hi ) << 32 ) | ( low & 0xffffffff );
+    }
+    auto hi  = dd4hep::ConditionKey::itemCode( "/world" );
+    auto low = dd4hep::ConditionKey::itemCode( s );
     return ( ( (dd4hep::Condition::key_type)hi ) << 32 ) | ( low & 0xffffffff );
   }
 } // namespace
@@ -209,7 +214,8 @@ namespace LHCb::Det::LbDD4hep {
     auto [deName, condKey] = LHCb::Detector::parseConditionIdentifier( output );
     auto de                = m_description.detector( std::string{deName} );
 
-    if ( this->msgLevel( MSG::DEBUG ) ) debug() << "Adding shared derivation for  " << output << endmsg;
+    if ( this->msgLevel( MSG::DEBUG ) )
+      debug() << "Adding shared derivation for  " << deName << ":" << condKey << endmsg;
 
     // Preparing the dependency to add
     auto dependency = std::make_unique<dd4hep::cond::ConditionDependency>( de, std::string{condKey},