python - Recursive version of 'reload'

Question

When I'm developing Python code, I usually test it in an ad-hoc way in the interpreter. I'll import some_module, test it, find a bug, fix the bug and save, and then use the built-in reload function to reload(some_module) and test again.

However, suppose that in some_module I have import some_other_module, and while testing some_module I discover a bug in some_other_module and fix it. Now calling reload(some_module) won't recursively re-import some_other_module. I have to either manually reimport the dependency (by doing something like reload(some_module.some_other_module), or import some_other_module; reload(some_other_module), or, if I've changed a whole bunch of dependencies and lost track of what I need to reload, I need to restart the entire interpreter.

What'd be more convenient is if there were some recursive_reload function, and I could just do recursive_reload(some_module) and have Python not only reload some_module, but also recursively reload every module that some_module imports (and every module that each of those modules imports, and so on) so that I could be sure that I wasn't using an old version of any of the other modules upon which some_module depends.

I don't think there's anything built in to Python that behaves like the recursive_reload function I describe here, but is there an easy way to hack such a thing together?

Answer 1

I've run up against the same issue, and you inspired me to actually solve the problem.

from types import ModuleType

try:
    from importlib import reload  # Python 3.4+
except ImportError:
    # Needed for Python 3.0-3.3; harmless in Python 2.7 where imp.reload is just an
    # alias for the builtin reload.
    from imp import reload

def rreload(module):
    """Recursively reload modules."""
    reload(module)
    for attribute_name in dir(module):
        attribute = getattr(module, attribute_name)
        if type(attribute) is ModuleType:
            rreload(attribute)

Or, if you are using IPython, just use dreload or pass --deep-reload on startup.