title: ArgumentError: wrong number of arguments (given 0, expected 1) - Ruby
body: <p>I had a test suite( hellow_world_test.rb) which has the following </p>
  
  <pre><code>#!/usr/bin/env ruby
  begin
    gem 'minitest', '&gt;= 5.0.0'
    require 'minitest/autorun'
    require_relative 'hello_world'
  rescue Gem::LoadError =&gt; e
    puts "\nMissing Dependency:\n#{e.backtrace.first} #{e.message}"
    puts 'Minitest 5.0 gem must be installed for the xRuby track.'
  rescue LoadError =&gt; e
    puts "\nError:\n#{e.backtrace.first} #{e.message}"
    puts DATA.read
    exit 1
  end
  
  # Test data version:
  # deb225e Implement canonical dataset for scrabble-score problem (#255)
  
  class HelloWorldTest &lt; Minitest::Test
    def test_no_name
      assert_equal 'Hello, World!', HelloWorld.hello()
    end
  
    def test_sample_name 
      assert_equal 'Hello, Alice!', HelloWorld.hello('Alice')
    end
  
    def test_other_sample_name
      assert_equal 'Hello, Bob!', HelloWorld.hello('Bob')
    end
  end
  
  __END__
  </code></pre>
  
  <p>On the basis of that I had implemented the code like  below</p>
  
  <pre><code>class HelloWorld
      def self.hello
          "Hello, World!"
      end
  
      def self.hello(named)
          "Hello, #{named}!"
      end
  end
  </code></pre>
  
  <p>And right now my two test cases are passing and the first test case is returning </p>
  
  <blockquote>
    <p>ArgumentError: wrong number of arguments (given 0, expected 1)
        /Users/vijay/Codes/Ruby/ruby/hello-world/hello_world.rb:7:in <code>hello'
        hello_world_test.rb:21:in</code>test_no_name'</p>
  </blockquote>
  
  <p>Can some body help me on this? </p>