Python & Go | Check if lines in one file are in another file

matching-lines.go

package main

import (
	"bufio"
	"fmt"
	"os"
	"strings"
)

func main() {

	var userLogins int

	usersFile, err := os.Open("users_list.txt")
	if err != nil {
		panic(err)
	}
	defer usersFile.Close()

	loginsFile, err := os.Open("logins.txt")
	if err != nil {
		panic(err)
	}
	defer loginsFile.Close()

	usersScanner := bufio.NewScanner(usersFile)
	loginsScanner := bufio.NewScanner(loginsFile)

	for usersScanner.Scan() {

		user := strings.ToLower(usersScanner.Text())

		for loginsScanner.Scan() {

			login := strings.ToLower(loginsScanner.Text())
			if user == login {
				userLogins++
			}
		}

		if err := loginsScanner.Err(); err != nil {
			panic(err)
		}
	}

	if err := usersScanner.Err(); err != nil {
		panic(err)
	}

	fmt.Printf("%d matching user logins\n", userLogins)
}

matching_lines.py

users_fh = open("users_list.txt")
logins_fh = open("logins.txt")

matching_user_logins = 0

for user in users_fh:
    user = user.strip().lower()

    # https://stackoverflow.com/questions/34553559/python-nested-loops-only-working-on-the-first-pass
    logins_fh.seek(0)

    for login in logins_fh:
        login = login.strip().lower()
        if user == login:
            matching_user_logins += 1

users_fh.close()
logins_fh.close()

print("{} matching user logins".format(matching_user_logins))

Added Go code as a separate "file" to this Gist. I'm thinking I'd be better served by setting up a small repo for this work.

Added Go code as a separate "file" to this Gist. I'm thinking I'd be better served by setting up a small repo for this work.

I spun off local test code to prototype this.

Note to self: Look in the check-if-lines-in-file-are-in-another-file branch.