use String#casecmp for case insensitive comparison (#20369)

Contributed by Go MAEDA.

git-svn-id: http://svn.redmine.org/redmine/trunk@14484 e93f8b46-1217-0410-a6f0-8f06a7374b81

app/controllers/account_controller.rb

@@ -102,7 +102,7 @@ class AccountController < ApplicationController
         token = Token.new(:user => user, :action => "recovery")
         if token.save
           # Don't use the param to send the email
-          recipent = user.mails.detect {|e| e.downcase == email.downcase} || user.mail
+          recipent = user.mails.detect {|e| email.casecmp(e) == 0} || user.mail
           Mailer.lost_password(token, recipent).deliver
           flash[:notice] = l(:notice_account_lost_email_sent)
           redirect_to signin_path

app/helpers/application_helper.rb

@@ -609,7 +609,7 @@ module ApplicationHelper
       parsed << text
       if tag
         if closing
-          if tags.last == tag.downcase
+          if tags.last.casecmp(tag) == 0
             tags.pop
           end
         else

app/models/custom_field.rb

@@ -144,7 +144,7 @@ class CustomField < ActiveRecord::Base
     possible_values_options = possible_values_options(customized)
     if possible_values_options.present?
       keyword = keyword.to_s.downcase
-      if v = possible_values_options.detect {|text, id| text.downcase == keyword}
+      if v = possible_values_options.detect {|text, id| keyword.casecmp(text)  == 0}
         if v.is_a?(Array)
           v.last
         else

app/models/mail_handler.rb

@@ -92,7 +92,7 @@ class MailHandler < ActionMailer::Base
     @handler_options = options
     sender_email = email.from.to_a.first.to_s.strip
     # Ignore emails received from the application emission address to avoid hell cycles
-    if sender_email.downcase == Setting.mail_from.to_s.strip.downcase
+    if sender_email.casecmp(Setting.mail_from.to_s.strip) == 0
       if logger
         logger.info  "MailHandler: ignoring email from Redmine emission address [#{sender_email}]"
       end
@@ -547,18 +547,19 @@ class MailHandler < ActionMailer::Base
     assignable = issue.assignable_users
     assignee = nil
     assignee ||= assignable.detect {|a|
-                   a.mail.to_s.downcase == keyword ||
-                     a.login.to_s.downcase == keyword
+                   keyword.casecmp(a.mail.to_s) == 0 ||
+                     keyword.casecmp(a.login.to_s) == 0
                  }
     if assignee.nil? && keyword.match(/ /)
       firstname, lastname = *(keyword.split) # "First Last Throwaway"
       assignee ||= assignable.detect {|a|
-                     a.is_a?(User) && a.firstname.to_s.downcase == firstname &&
-                       a.lastname.to_s.downcase == lastname
+                     a.is_a?(User) &&
+                       firstname.casecmp(a.firstname.to_s) == 0 &&
+                       lastname.casecmp(a.lastname.to_s) == 0
                    }
     end
     if assignee.nil?
-      assignee ||= assignable.detect {|a| a.name.downcase == keyword}
+      assignee ||= assignable.detect {|a| keyword.casecmp(a.name) == 0}
     end
     assignee
   end

app/models/principal.rb

@@ -130,7 +130,7 @@ class Principal < ActiveRecord::Base
     if principal.nil?
       -1
     elsif self.class.name == principal.class.name
-      self.to_s.downcase <=> principal.to_s.downcase
+      self.to_s.casecmp(principal.to_s)
     else
       # groups after users
       principal.class.name <=> self.class.name

app/models/project.rb

@@ -531,7 +531,7 @@ class Project < ActiveRecord::Base
   end
 
   def <=>(project)
-    name.downcase <=> project.name.downcase
+    name.casecmp(project.name)
   end
 
   def to_s