♻️ Extract SASL::Authenticators#normalize_name [🚧 tests]

This was used in several different places, so it's better to DRY up the
implementation.

Author: nevans

lib/net/imap.rb

@@ -1342,7 +1342,7 @@ def starttls(**options)
     def authenticate(mechanism, *creds,
                      sasl_ir: config.sasl_ir,
                      **props, &callback)
-      mechanism = mechanism.to_s.tr("_", "-").upcase
+      mechanism = SASL::Authenticators.normalize_name(mechanism)
       authenticator = SASL.authenticator(mechanism, *creds, **props, &callback)
       cmdargs = ["AUTHENTICATE", mechanism]
       if sasl_ir && capable?("SASL-IR") && auth_capable?(mechanism) &&

lib/net/imap/sasl/authentication_exchange.rb

@@ -81,7 +81,7 @@ def self.build(client, mechanism, *args, sasl_ir: true, **kwargs, &block)
 
         def initialize(client, mechanism, authenticator, sasl_ir: true)
           @client = client
-          @mechanism = -mechanism.to_s.upcase.tr(?_, ?-)
+          @mechanism = Authenticators.normalize_name(mechanism)
           @authenticator = authenticator
           @sasl_ir = sasl_ir
           @processed = false

lib/net/imap/sasl/authenticators.rb

@@ -21,6 +21,10 @@ module Net::IMAP::SASL
   # ScramSHA1Authenticator for examples.
   class Authenticators
 
+    # Normalize the mechanism name as an uppercase string, with underscores
+    # converted to dashes.
+    def self.normalize_name(mechanism) -mechanism.to_s.upcase.tr(?_, ?-) end
+
     # Create a new Authenticators registry.
     #
     # This class is usually not instantiated directly.  Use SASL.authenticators
@@ -65,7 +69,7 @@ def names; @authenticators.keys end
     # lazily loaded from <tt>Net::IMAP::SASL::#{name}Authenticator</tt> (case is
     # preserved and non-alphanumeric characters are removed..
     def add_authenticator(name, authenticator = nil)
-      key = -name.to_s.upcase.tr(?_, ?-)
+      key = Authenticators.normalize_name(name)
       authenticator ||= begin
         class_name = "#{name.gsub(/[^a-zA-Z0-9]/, "")}Authenticator".to_sym
         auth_class = nil
@@ -79,12 +83,12 @@ def add_authenticator(name, authenticator = nil)
 
     # Removes the authenticator registered for +name+
     def remove_authenticator(name)
-      key = -name.to_s.upcase.tr(?_, ?-)
+      key = Authenticators.normalize_name(name)
       @authenticators.delete(key)
     end
 
     def mechanism?(name)
-      key = -name.to_s.upcase.tr(?_, ?-)
+      key = Authenticators.normalize_name(name)
       @authenticators.key?(key)
     end
 
@@ -105,7 +109,7 @@ def mechanism?(name)
     #   only.  Protocol client users should see refer to their client's
     #   documentation, e.g. Net::IMAP#authenticate.
     def authenticator(mechanism, ...)
-      key = -mechanism.to_s.upcase.tr(?_, ?-)
+      key = Authenticators.normalize_name(mechanism)
       auth = @authenticators.fetch(key) do
         raise ArgumentError, 'unknown auth type - "%s"' % key
       end