Helping people moving from model_mommy to model_bakery

from_mommy_to_bakery.py

"""
Migrate from model_mommy to model_bakery.

``python from_mommy_to_bakery.py --dry-run``

Please check your dependency files.
"""

import argparse
import os
import re

PACKAGE_NAME = r'\bmodel_mommy\b'
PACKAGE_NAME_PATTERN = re.compile(PACKAGE_NAME)
PACKAGE_RECIPES = r'\bmommy_recipes\b'
PACKAGE_RECIPES_PATTERN = re.compile(PACKAGE_RECIPES)
PACKAGE_LEGACY_MODULE = r'\bmommy\b'
PACKAGE_LEGACY_MODULE_PATTERN = re.compile(PACKAGE_LEGACY_MODULE)

legacy_and_new = [
    {'old': PACKAGE_NAME_PATTERN, 'new': r'model_bakery'},
    {'old': PACKAGE_RECIPES_PATTERN, 'new': r'baker_recipes'},
    {'old': PACKAGE_LEGACY_MODULE_PATTERN, 'new': r'baker'},
]
exclude = [
    'node_modules', 'venv', '.git', 'sql', 'docs',
    'from_mommy_to_bakery.py', 'Pipfile', 'Pipfile.lock'
]


def _find_changes(content, pattern, new_value):
    new_content, substitutions = re.subn(pattern, new_value, content)
    return new_content, substitutions > 0


def _rename_recipe_file(to_be_renamed, dry_run):
    if dry_run is True:
        print('Will be renamed:')
    for old_recipe_file in to_be_renamed:
        root = old_recipe_file[:old_recipe_file.rfind('/')]
        if dry_run is False:
            os.rename(old_recipe_file, f'{root}/baker_recipes.py')
        else:
            print(old_recipe_file)


def _replace_legacy_terms(file_path, dry_run):
    try:
        content = open(file_path, 'r').read()
    except UnicodeDecodeError:
        return
    changed = []
    for patterns in legacy_and_new:
        old, new = patterns['old'], patterns['new']
        content, has_changed = _find_changes(content, old, new)
        changed.append(has_changed)

    if any(changed):
        if dry_run is False:
            open(file_path, 'w').write(content)
        else:
            print(file_path)


def check_files(dry_run):
    excluded_by_gitignore = [
        folder_or_file.strip()
        for folder_or_file in open('.gitignore').readlines()
    ]
    exclude.extend(excluded_by_gitignore)

    to_be_renamed = []
    for root, dirs, files in os.walk('.', topdown=True):
        dirs[:] = [
            directory
            for directory in dirs
            if directory not in exclude
        ]

        for file_ in files:
            if file_ in exclude or not file_.endswith('.py'):
                continue                

            file_path = f'{root}/{file_}'
            if file_ == 'mommy_recipes.py':
                to_be_renamed.append(file_path)
            _replace_legacy_terms(file_path, dry_run)

    _rename_recipe_file(to_be_renamed, dry_run)


if __name__ == '__main__':
    description = 'Help you to migrate from model_mommy to model_bakery.'
    parser = argparse.ArgumentParser(description=description)
    parser.add_argument(
        '--dry-run', dest='dry_run', action='store_true',
        help='See which files will be changed.'
    )

    args = parser.parse_args()
    check_files(args.dry_run)