Simplify logic

lib/msf/ui/console/command_dispatcher/db.rb

@@ -888,12 +888,12 @@ class Db
       query.find_each do |core|
 
         # Exclude non-blank username creds if that's what we're after
-        if user && user.empty? && !(core.public && core.public.username.blank?)
+        if user == "" && !(core.public && core.public.username.blank?)
           next
         end
 
         # Exclude non-blank password creds if that's what we're after
-        if pass && pass.empty? && !(core.private && core.private.data.blank?)
+        if pass == "" && !(core.private && core.private.data.blank?)
           next
         end
 

spec/lib/msf/ui/console/command_dispatcher/db_spec.rb

@@ -145,7 +145,7 @@ describe Msf::Ui::Console::CommandDispatcher::Db do
 
         context "and when the username is blank" do
           it "should show a user that matches the given expression" do
-            db.cmd_creds("-u", blank_username )
+            db.cmd_creds("-u", blank_username)
             @output.should =~ [
               "Credentials",
               "===========",
@@ -158,7 +158,7 @@ describe Msf::Ui::Console::CommandDispatcher::Db do
         end
         context "and when the password is blank" do
           it "should show a user that matches the given expression" do
-            db.cmd_creds("-P", blank_password )
+            db.cmd_creds("-P", blank_password)
             @output.should =~ [
               "Credentials",
               "===========",