List used classes on an apktool decompiled application

smali_ls_classes.py

#!/usr/bin/env python3
# Public Domain
#
# Lists used classes on a apktool decompiled application
# It outputs:
    #  to stderr provided/compiled classes
    #  to stdout imported/system   classes
# Don't play with it too much, it's a bit shy
# UwU
 
import re
import os
import sys


## Extract classes from smali file
#  Args:
    #  filename@str: the path of the source file
#
#  Returns:
    #  set(EMPTY): No class found on file
    #  set(str): Contained unique classes
def extract_classes_from(filename):
	extracted_classes=set()

	with open(filename, 'r') as smali_file:
		get_classes=re.compile(r'\sL([\w/]+);').findall

		for line in smali_file:
			extracted_classes = extracted_classes.union(
				get_classes(line)
				)
	return extracted_classes


## Extracts classes recurring the files of a directory
#  Args:
    #  directory@str: path to recurse on
#
#  Returns:
    #  set(EMPTY): No class found in directory, or unsupported smali extension
    #  set(str): Unique classes contained in files
def find_all_classes_in(directory):
	classes = set()
	
	for root, _, files in os.walk(directory):
		for filename in files:
			filename = os.path.join(root, filename)
			
			if ".smali" in os.path.splitext(filename):
				classes = classes.union(
					extract_classes_from(filename)
					)
	return classes


if __name__ == "__main__":
	classes = find_all_classes_in(os.getcwd())
	provided_classes = set()

	print_stderr = sys.stderr.write
	print_stdout = sys.stdout.write

	# Print provided classes
	for smali_class in classes:
		for directory in os.listdir():
			if "smali" in directory:
				if os.path.exists(os.path.join(directory, smali_class + ".smali")):
					provided_classes.add(smali_class)
					print_stderr(smali_class+', ')
					
	# Print imported classes
	classes = classes.difference(provided_classes)
	print_stdout(', '.join('{}'.format(smali_class) for smali_class in classes))

# Di end
# Written by Hattshire in Kakoune with <3