feat: drop email-password session authentication.

This commit drops old email/password authentication for New function.
It violates Discord ToS and due to recent changes in rules for community resources on Discord API Docs it needs to be dropped.

discord.go

@@ -24,32 +24,12 @@ import (
 // VERSION of DiscordGo, follows Semantic Versioning. (http://semver.org/)
 const VERSION = "0.23.0"
 
-// ErrMFA will be risen by New when the user has 2FA.
-var ErrMFA = errors.New("account has 2FA enabled")
-
-// New creates a new Discord session and will automate some startup
-// tasks if given enough information to do so.  Currently you can pass zero
-// arguments and it will return an empty Discord session.
-// There are 3 ways to call New:
-//     With a single auth token - All requests will use the token blindly
-//         (just tossing it into the HTTP Authorization header);
-//         no verification of the token will be done and requests may fail.
-//         IF THE TOKEN IS FOR A BOT, IT MUST BE PREFIXED WITH `BOT `
-//         eg: `"Bot <token>"`
-//         IF IT IS AN OAUTH2 ACCESS TOKEN, IT MUST BE PREFIXED WITH `Bearer `
-//         eg: `"Bearer <token>"`
-//     With an email and password - Discord will sign in with the provided
-//         credentials.
-//     With an email, password and auth token - Discord will verify the auth
-//         token, if it is invalid it will sign in with the provided
-//         credentials. This is the Discord recommended way to sign in.
-//
-// NOTE: While email/pass authentication is supported by DiscordGo it is
-// HIGHLY DISCOURAGED by Discord. Please only use email/pass to obtain a token
-// and then use that authentication token for all future connections.
-// Also, doing any form of automation with a user (non Bot) account may result
-// in that account being permanently banned from Discord.
-func New(args ...interface{}) (s *Session, err error) {
+// New creates a new Discord session with provided token.
+// If the token is for a bot, it must be prefixed with "Bot ".
+// 		e.g. "Bot ..."
+// Or if it is an OAuth2 token, it must be prefixed with "Bearer "
+//		e.g. "Bearer ..."
+func New(token string) (s *Session, err error) {
 
 	// Create an empty Session interface.
 	s = &Session{
@@ -75,87 +55,8 @@ func New(args ...interface{}) (s *Session, err error) {
 	s.Identify.Properties.OS = runtime.GOOS
 	s.Identify.Properties.Browser = "DiscordGo v" + VERSION
 	s.Identify.Intents = MakeIntent(IntentsAllWithoutPrivileged)
-
-	// If no arguments are passed return the empty Session interface.
-	if args == nil {
-		return
-	}
-
-	// Variables used below when parsing func arguments
-	var auth, pass string
-
-	// Parse passed arguments
-	for _, arg := range args {
-
-		switch v := arg.(type) {
-
-		case []string:
-			if len(v) > 3 {
-				err = fmt.Errorf("too many string parameters provided")
-				return
-			}
-
-			// First string is either token or username
-			if len(v) > 0 {
-				auth = v[0]
-			}
-
-			// If second string exists, it must be a password.
-			if len(v) > 1 {
-				pass = v[1]
-			}
-
-			// If third string exists, it must be an auth token.
-			if len(v) > 2 {
-				s.Identify.Token = v[2]
-				s.Token = v[2] // TODO: Remove, Deprecated - Kept for backwards compatibility.
-			}
-
-		case string:
-			// First string must be either auth token or username.
-			// Second string must be a password.
-			// Only 2 input strings are supported.
-
-			if auth == "" {
-				auth = v
-			} else if pass == "" {
-				pass = v
-			} else if s.Token == "" {
-				s.Identify.Token = v
-				s.Token = v // TODO: Remove, Deprecated - Kept for backwards compatibility.
-			} else {
-				err = fmt.Errorf("too many string parameters provided")
-				return
-			}
-
-			//		case Config:
-			// TODO: Parse configuration struct
-
-		default:
-			err = fmt.Errorf("unsupported parameter type provided")
-			return
-		}
-	}
-
-	// If only one string was provided, assume it is an auth token.
-	// Otherwise get auth token from Discord, if a token was specified
-	// Discord will verify it for free, or log the user in if it is
-	// invalid.
-	if pass == "" {
-		s.Identify.Token = auth
-		s.Token = auth // TODO: Remove, Deprecated - Kept for backwards compatibility.
-	} else {
-		err = s.Login(auth, pass)
-		// TODO: Remove last s.Token part, Deprecated - Kept for backwards compatibility.
-		if err != nil || s.Identify.Token == "" || s.Token == "" {
-			if s.MFA {
-				err = ErrMFA
-			} else {
-				err = fmt.Errorf("Unable to fetch discord authentication token. %v", err)
-			}
-			return
-		}
-	}
+	s.Identify.Token = token
+	s.Token = token
 
 	return
 }