You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: prepare_test_dir.m
    path of file: ./repos/prima/matlab/tests/private
    
    the code of the file until where you have to start completion: function test_dir = prepare_test_dir(solver, test_name, test_options)
%PREPARE_TEST_DIR prepares a copy of the package in `test_dir` for the solver named `solver and test
% named `test_name`,  with options in `test_options`, which specifies the competitor etc.


    
function test_dir = prepare_test_dir(solver, test_name, test_options)
%PREPARE_TEST_DIR prepares a copy of the package in `test_dir` for the solver named `solver and test
% named `test_name`,  with options in `test_options`, which specifies the competitor etc.

if verLessThan('matlab', '9.10') && ispc
    callstack = dbstack;
    funname = callstack(1).name; % Name of the current function
    warning('%s may FAIL because ''copyfile'' of MATLAB R2020b or earlier may raise an error when handling unix symbolic links under Windows.', funname);
end