[RDF] Don't search for input branches when snapshotting Redefine.

hageboeck · hageboeck · commit 155dcdb55684 · 2025-08-07T11:33:02.000+02:00
When columns got redefined, snapshot was trying to still find input
columns for the outputs. That should not be the case since none of the
properties of the input branch need to be transferred.
diff --git a/tree/dataframe/src/RDFSnapshotHelpers.cxx b/tree/dataframe/src/RDFSnapshotHelpers.cxx
@@ -244,7 +244,7 @@ void SetBranchesHelper(TTree *inputTree, TTree &outputTree, ROOT::Internal::RDF:
                        void *&actionHelperBranchPtrAddress, bool isDefine)
 {
 
-   auto *inputBranch = SearchForBranch(inputTree, inputBranchName);
+   auto *inputBranch = isDefine ? nullptr : SearchForBranch(inputTree, inputBranchName);
 
    // Respect the original bufsize and splitlevel arguments
    // In particular, by keeping splitlevel equal to 0 if this was the case for `inputBranch`, we avoid

Original file line number	Diff line number	Diff line change
`@@ -244,7 +244,7 @@ void SetBranchesHelper(TTree *inputTree, TTree &outputTree, ROOT::Internal::RDF:`
`244`	`244`	`void *&actionHelperBranchPtrAddress, bool isDefine)`
`245`	`245`	`{`
`246`	`246`
`247`		`- auto *inputBranch = SearchForBranch(inputTree, inputBranchName);`
	`247`	`+ auto *inputBranch = isDefine ? nullptr : SearchForBranch(inputTree, inputBranchName);`
`248`	`248`
`249`	`249`	`// Respect the original bufsize and splitlevel arguments`
`250`	`250`	// In particular, by keeping splitlevel equal to 0 if this was the case for `inputBranch`, we avoid