Minimum reproduction of change in behaviour of LoadedPrograms in ProgramTest after solana version 1.17.6
The 1.17.6/ folder and 1.18.9/ folder contains the exact same code of loading the spl stake pool program into a ProgramTest by calling ProgramTest::add_account() on spl-stake-pool-prog.json and spl-stake-pool-prog-data.json (the program and program data accounts cloned from mainnet), and then trying to execute a transaction that calls the program against the started program test.
In 1.17.6, the program executes normally.
In 1.18.9, it hangs and eventually fails with RpcError::DeadlineExceeded. If simulating instead, it throws TransactionError::InvalidProgramForExecution. This happens even after warping the context past the program's last upgrade slot and epoch.
cd into the respective folders and run cargo test