Make the scope optional

spec/googleauth/get_application_default_spec.rb

@@ -104,6 +104,18 @@ describe '#get_application_default' do
       end
     end
 
+    it 'succeeds with default file without a scope' do
+      ENV.delete(@var_name) unless ENV[@var_name].nil?
+      Dir.mktmpdir do |dir|
+        key_path = File.join(dir, '.config',
+                             CredentialsLoader::WELL_KNOWN_PATH)
+        FileUtils.mkdir_p(File.dirname(key_path))
+        File.write(key_path, cred_json_text)
+        ENV['HOME'] = dir
+        expect(Google::Auth.get_application_default).to_not be_nil
+      end
+    end
+
     it 'succeeds without default file or env if on compute engine' do
       stubs = Faraday::Adapter::Test::Stubs.new do |stub|
         stub.get('/') do |_env|

spec/googleauth/service_account_spec.rb

@@ -47,8 +47,8 @@ describe Google::Auth::ServiceAccountCredentials do
   before(:example) do
     @key = OpenSSL::PKey::RSA.new(2048)
     @client = ServiceAccountCredentials.new(
-        'https://www.googleapis.com/auth/userinfo.profile',
-        StringIO.new(cred_json_text))
+        StringIO.new(cred_json_text),
+        'https://www.googleapis.com/auth/userinfo.profile')
   end
 
   def make_auth_stubs(opts = {})

spec/googleauth/user_refresh_spec.rb

@@ -47,8 +47,8 @@ describe Google::Auth::UserRefreshCredentials do
   before(:example) do
     @key = OpenSSL::PKey::RSA.new(2048)
     @client = UserRefreshCredentials.new(
-        'https://www.googleapis.com/auth/userinfo.profile',
-        StringIO.new(cred_json_text))
+        StringIO.new(cred_json_text),
+        'https://www.googleapis.com/auth/userinfo.profile')
   end
 
   def make_auth_stubs(opts = {})