Success story, but had to mock require/module/exports manually

[akaihola]

I wanted to use the Easysync library in Etherpad Lite from Python. To my surprise, I succeeded with relatively little tweaking, and the test suite runs successfully.

To replicate what I did, you can install Js2Py and and run this in the root of the Etherpad Lite repository:

from pathlib import Path

import js2py.pyjs


def import_js(path, **modules):

    def require(js_path):
        for module_name, module in modules.items():
            if js_path.to_python().endswith(f'/{module_name}'):
                return module

    exports = js2py.pyjs.Scope({})
    context = js2py.EvalJs({'require': require,
                            'exports': exports,
                            'module': {'exports': exports}})
    js2py.run_file(path, context)
    return context


ETHERPAD_SRC_DIR = Path('./src')
ETHERPAD_JS_DIR = ETHERPAD_SRC_DIR / 'static/js'
changeset = import_js(ETHERPAD_JS_DIR / 'Changeset.js').exports
attributepool = import_js(ETHERPAD_JS_DIR / 'AttributePool.js').module.exports
easysync_tests = import_js(ETHERPAD_SRC_DIR / 'node/easysync_tests.js',
                           Changeset=changeset,
                           AttributePool=attributepool)

The problem I had to work around was missing support for require and catching exports or module.exports from the JavaScript modules. I wonder if I'm missing something, or whether Js2Py could improve support for JavaScript modules to make this work without extra effort? Are #57, #63 and #150 related to this?