Find where regex fails to match a string using pypi package re-assert

find_regex_mismatch.py

# DESCRIPTION
# This script can be run on repl.it to find out where a regex expression
# fails.  This uses the python library re-assert that can be found here:
# https://pypi.org/project/re-assert/


# SETUP
# Use online python IDE at
# https://repl.it/languages/python3

# 1) create new file 'requiements.txt' with following content:
#    (remove the leading #)
#re-assert==1.0.0

# 2) replace the main.py file with the following and run
#    (or cut/paste this entire file
import re
from re_assert import Matches
test = Matches('\d{3}-\d{3}-\d{4}')
test.assert_matches('1123-456-7890')


# EXAMPLE 1
# cut and paste to console
test = Matches('\d{3}-\d{3}-\d{4}')   # regex here
test.assert_matches('1123-456-7890')  # expect to match

# EXAMPLE 2
# cut and paste to console
test = Matches('\d{3}-\d{3}--\d{4}')  # regex here
test.assert_matches('123-456-7890')   # expect to match