Best regex pattern to replace input function from a separate python file-CodePudding

I am new to regex so please explain how you got to the answer. Anyway I want to know the best way to match input function from a separate python file.

For example:

match.py

a = input("Enter a number")
b = input()
print(a b)

Now I want to match ONLY the input statement and replace it with a random number. I will do this in a separate file main.py. So my aim is to replace input function in the match.py with a random numbers so I can check the output will come as expected. You can think of match.py like a coding exercise where he writes the code in that file and main.py will be the file where it evaluates if the users code is right. And to do that I need to replace the input myself and check if it works for all kinds of inputs. I looked for "regex patterns for python input function" but the search did not work right. I have a current way of doing it but I don't think it works in all kinds of cases. I need a perfect pattern which works in all kinds of cases referring to the python syntax. Here is the current main.py I have (It doesn't work for all cases I mean when you write a string with single quote, it does not replace but here is the problem I can just add single quote in pattern but I also need to detect if both are used):

# Evaluating python file checking if input 2 numbers and print sum is correct

import re
import subprocess

input_pattern = re.compile(r"input\s?\([\"]?[\w]*[\"]?\)")
file = open("match.py", 'r')
read = file.read()
file.close()

code = read

matches = input_pattern.findall(code)

for match in matches:
    code = code.replace(match, '8')

file = open("match.py", 'w')
file.write(code)
file.close()

process = subprocess.Popen('python3 match.py', stdout=subprocess.PIPE, stderr=subprocess.PIPE, shell=True)

out = process.communicate()[0]
print(out == b"16\n")

file = open("match.py", 'w')
file.write(read)
file.close()

Please let me know if you don't understand this question.

CodePudding user response：

The following regex statement is very close to what you need:

input\s?\((?(?=[\"\'])[\"\'].*[\"\']\)|\))

I am using a conditional regex statement. However, I think it may need a nested conditional to avoid the situation that the user enters something like: input(' text ") But hopefully this gets you on the right track.