Observe function calls

function_observe_script.lua

---@param fSrc function
---@param fDst function
---@param fResultCallback function
function hook(fSrc, fDst, fResultCallback)
    return function(...)
        --DebugUtil.printCallingFunctionLocation()
        if type(fResultCallback) == 'function' then
            if type(fDst) == 'function' then
                fDst(...)
            end
            return fResultCallback(fSrc(...))
        else
            if type(fDst) == 'function' then
                fDst(...)
            end
            return fSrc(...)
        end
    end
end


local original_function = ConfigurationManager.addConfigurationType

-- Only observe function arguments
ConfigurationManager.addConfigurationType = hook(original_function, function(...)
    print('Arguments:')
    print_r(...)
end)

-- Observe function arguments and return value from original function
ConfigurationManager.addConfigurationType = hook(original_function, function(...)
    print('Arguments:')
    print_r(...)
end, function(...)
    print('Function result:')
    print_r(...)
    
    return ...  -- IMPORTANT! pass return value(s) back to calling function
end)