FIX: nil emails are invalid

lib/email.rb

@@ -7,6 +7,9 @@ require_dependency 'email/styles'
 module Email
 
   def self.is_valid?(email)
+
+    return false unless String === email
+
     parser = Mail::RFC2822Parser.new
     parser.root = :addr_spec
     result = parser.parse(email)

spec/components/email/email_spec.rb

@@ -5,6 +5,10 @@ describe Email do
 
   describe "is_valid?" do
 
+    it 'treats a nil as invalid' do
+      expect(Email.is_valid?(nil)).to eq(false)
+    end
+
     it 'treats a good email as valid' do
       expect(Email.is_valid?('sam@sam.com')).to eq(true)
     end