[RF] Fix RooAbsCollection::contentsString() for empty collections

TomasDado · guitargeek · commit 5fc24b4b8167 · 2025-10-25T12:14:03.000+02:00
Closes #20189.
diff --git a/roofit/roofitcore/src/RooAbsCollection.cxx b/roofit/roofitcore/src/RooAbsCollection.cxx
@@ -1143,7 +1143,9 @@ std::string RooAbsCollection::contentsString() const
     retVal += ",";
   }
 
-  retVal.erase(retVal.end()-1);
+  if (!retVal.empty()) {
+    retVal.erase(retVal.end()-1);
+  }
 
   return retVal;
 }

Original file line number	Diff line number	Diff line change
`@@ -1143,7 +1143,9 @@ std::string RooAbsCollection::contentsString() const`
`1143`	`1143`	`retVal += ",";`
`1144`	`1144`	`}`
`1145`	`1145`
`1146`		`- retVal.erase(retVal.end()-1);`
	`1146`	`+ if (!retVal.empty()) {`
	`1147`	`+ retVal.erase(retVal.end()-1);`
	`1148`	`+ }`
`1147`	`1149`
`1148`	`1150`	`return retVal;`
`1149`	`1151`	`}`