fix: exit with error code if nothing was read

modules/conop/src/chemdict_tool.cc

@@ -116,6 +116,11 @@ int main(int argc, char const *argv[])
     compound_lib.reset();
     cdp.SetCompoundLib(in_mem_lib);
     cdp.Parse();
+    if (cdp.GetImportedCount() == 0)
+    {
+      std::cout << "No compound imported from " << argv[2] << std::endl;
+      return 1;
+    }
     in_mem_lib->SetChemLibInfo();
     conop::CompoundLibPtr copy = in_mem_lib->Copy(argv[3]);
     if (! copy) {

modules/io/src/mol/chemdict_parser.cc

@@ -215,6 +215,7 @@ void ChemdictParser::OnEndData()
         }
       }
       lib_->AddCompound(compound_);
+      ++imported_count_;
     }
   }
 }

modules/io/src/mol/chemdict_parser.hh

@@ -44,7 +44,8 @@ public:
     bool ignore_reserved=false, bool ignore_obsolete=false):
     StarParser(stream), compound_(new conop::Compound("UNK")), 
     last_(0), loop_type_(DONT_KNOW), dialect_(dialect),
-    ignore_reserved_(ignore_reserved), ignore_obsolete_(ignore_obsolete)
+    ignore_reserved_(ignore_reserved), ignore_obsolete_(ignore_obsolete),
+    imported_count_(0)
   {
     this->InitTypeMap();
     this->InitPDBXTypeMap();
@@ -65,6 +66,12 @@ public:
   {
     lib_=lib;
   }
+
+  /// \brief Get the number of compounds that were successfully parsed
+  int GetImportedCount()
+  {
+    return imported_count_;
+  }
 private:
   void InitTypeMap();  
   void InitPDBXTypeMap();
@@ -98,6 +105,7 @@ private:
   conop::Compound::Dialect                dialect_;
   bool                                    ignore_reserved_;
   bool                                    ignore_obsolete_;
+  int                                     imported_count_;
 };