[python] Improve CPyCppyy heuristic for Clone methods #18423
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Thank you very much for making this PR and explaining the problem in the commit message!
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The heuristic checks if the token "Clone" is present in the method name being called and gives Python the ownership of the returned object. This is valid behaviour for methods such as `TObject::Clone` where the ownership of the returned value is given to the caller. But the `CPPOverload::Set` method gets as the method name being called the actual function name concatenated with the full template argument list. For example, given the function ``` template <typename T> void foo(); ``` When it passes through this method its name will be `foo<T>`. This behaviour has an undesired side-effect. When `T` is a type with the token `Clone` in its name, then the heuristic will trigger and Python will take ownership of the return value. This is the root cause of the problem seen at root-project#16725, where `T` is `TClonesArray`. This commit improves on the heuristic by stripping the template argument list from the method name before checking for the presence of the token. Co-authored-by: Jonas Rembser <jonas.rembser@cern.ch>
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Test Results 18 files 18 suites 4d 9h 38m 20s ⏱️ Results for commit 091a5ca. |
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The heuristic checks if the token "Clone" is present in the method name being called and gives Python the ownership of the returned object. This is valid behaviour for methods such as
TObject::Clonewhere the ownership of the returned value is given to the caller. But theCPPOverload::Setmethod gets as the method name being called the actual function name concatenated with the full template argument list. For example, given the functionWhen it passes through this method its name will be
foo<T>. This behaviour has an undesired side-effect. WhenTis a type with the tokenClonein its name, then the heuristic will trigger and Python will take ownership of the return value. This is the root cause of the problem seen at #16725, whereTisTClonesArray.This commit improves on the heuristic by stripping the template argument list from the method name before checking for the presence of the token.
Fixes #16725
Hopefully supersedes #18416