diff --git a/Rakefile b/Rakefile
index 094820349e1425bfe70e125f2d338b99397f0fec..220a4da38f35e61d1dd4c78e294489287d65cdbe 100644
--- a/Rakefile
+++ b/Rakefile
@@ -9,6 +9,7 @@ Rake::TestTask.new(:test) do |test|
   test.libs << 'lib' << 'test'
   test.pattern = 'test/**/*_test.rb'
   test.verbose = true
+  test.warning = true
 end
 
 begin
diff --git a/lib/ipaddress.rb b/lib/ipaddress.rb
index 19b526f3cb1186e5308dc0cc39680caa600af4b0..4f8c71f6a647dfd856ba32b2c0b84ffb1c0adda9 100644
--- a/lib/ipaddress.rb
+++ b/lib/ipaddress.rb
@@ -68,14 +68,14 @@ module IPAddress
   #
   def self.ntoa(uint)
     unless(uint.is_a? Numeric and uint <= 0xffffffff and uint >= 0)
-        raise(::ArgumentError, "not a long integer: #{uint.inspect}")
-      end
-      ret = []
-      4.times do 
-        ret.unshift(uint & 0xff)
-        uint >>= 8
-      end
-      ret.join('.')
+      raise(::ArgumentError, "not a long integer: #{uint.inspect}")
+    end
+    ret = []
+    4.times do 
+      ret.unshift(uint & 0xff)
+      uint >>= 8
+    end
+    ret.join('.')
   end
 
   #
diff --git a/lib/ipaddress/prefix.rb b/lib/ipaddress/prefix.rb
index 136f2d3457ca0cd77f369109ea76cd14a97c759d..e819800fbe5a6b3737868287ad0de57535bdd3ef 100644
--- a/lib/ipaddress/prefix.rb
+++ b/lib/ipaddress/prefix.rb
@@ -78,7 +78,7 @@ module IPAddress
       end
     end
     
-   end # class Prefix
+  end # class Prefix
 
 
   class Prefix32 < Prefix
diff --git a/test/ipaddress/ipv4_test.rb b/test/ipaddress/ipv4_test.rb
index 621f33c6ba8d4063397322bb8df5e0c59f38d7d9..56a78d0fd2b93a8e53a7abb0d3651a4f6eb67ac7 100644
--- a/test/ipaddress/ipv4_test.rb
+++ b/test/ipaddress/ipv4_test.rb
@@ -83,7 +83,7 @@ class IPv4Test < Minitest::Test
       assert_instance_of @klass, ip
     end
     assert_instance_of IPAddress::Prefix32, @ip.prefix
-    assert_raises (ArgumentError) do
+    assert_raises(ArgumentError) do
       @klass.new 
     end
   end
diff --git a/test/ipaddress/ipv6_test.rb b/test/ipaddress/ipv6_test.rb
index c7b8142952bcf1a84d94ca497da0e0c93baf040b..b43c9de7cf3890e500101fc6c64c444d5989b56b 100644
--- a/test/ipaddress/ipv6_test.rb
+++ b/test/ipaddress/ipv6_test.rb
@@ -26,9 +26,7 @@ class IPv6Test < Minitest::Test
       "::1" => 1,
       "0:0:0:0:0:0:0:0" => 0,
       "0:0:0::0:0:0" => 0,
-      "::" => 0,
-      "1080:0:0:0:8:800:200C:417A" => 21932261930451111902915077091070067066,
-      "1080::8:800:200C:417A" => 21932261930451111902915077091070067066}
+      "::" => 0}
       
     @invalid_ipv6 = [":1:2:3:4:5:6:7",
                      ":1:2:3:4:5:6:7",
diff --git a/test/ipaddress/mongoid_test.rb b/test/ipaddress/mongoid_test.rb
index b463e841ce35e2fa019c0f635fbf5f0c0a9c8166..4f3209305e8e94672db13e3884a4a0b80f439531 100644
--- a/test/ipaddress/mongoid_test.rb
+++ b/test/ipaddress/mongoid_test.rb
@@ -38,7 +38,7 @@ class MongoidTest < Minitest::Test
 
     @invalid_values.each do |invalid_value|
       # Invalid addresses should serialize to nil
-      assert_equal nil, IPAddress.mongoize(invalid_value)
+      assert_nil IPAddress.mongoize(invalid_value)
     end
   end
 
@@ -57,7 +57,7 @@ class MongoidTest < Minitest::Test
 
     @invalid_values.each do |invalid_value|
       # Invalid stored value should be loaded as nil
-      assert_equal nil, IPAddress.demongoize(invalid_value)
+      assert_nil IPAddress.demongoize(invalid_value)
     end
   end
 
@@ -67,4 +67,4 @@ class MongoidTest < Minitest::Test
     assert_equal IPAddress.mongoize(@valid_network4), IPAddress.evolve(@valid_network4)
   end
 
-end
\ No newline at end of file
+end
diff --git a/test/ipaddress/prefix_test.rb b/test/ipaddress/prefix_test.rb
index 1a0e2779d17ea4569cd2391b535609fa7c92e7bb..f0a3d8c953bb99569e353cc95cb7b879f2ef725b 100644
--- a/test/ipaddress/prefix_test.rb
+++ b/test/ipaddress/prefix_test.rb
@@ -132,7 +132,7 @@ class Prefix128Test < Minitest::Test
   end
 
   def test_initialize
-    assert_raises (ArgumentError) do
+    assert_raises(ArgumentError) do
       @klass.new 129
     end
     assert_instance_of @klass, @klass.new(64)