Use Net::HTTP instead of curl

There was some problem with command line parsing with a special character.

test/helper.rb

@@ -161,3 +161,17 @@ end
 def fixture_file(filename)
  File.join(File.dirname(__FILE__), 'fixtures', filename)
 end
+
+def assert_success_response(url)
+  Net::HTTP.get_response(URI.parse(url)) do |response|
+    assert_equal "200", response.code,
+      "Expected HTTP response code 200, got #{response.code}"
+  end
+end
+
+def assert_not_found_response(url)
+  Net::HTTP.get_response(URI.parse(url)) do |response|
+    assert_equal "404", response.code,
+      "Expected HTTP response code 404, got #{response.code}"
+  end
+end

test/storage/s3_live_test.rb

@@ -91,13 +91,13 @@ unless ENV["S3_BUCKET"].blank?
       end
 
       should "be accessible" do
-        assert_match /200 OK/, `curl -I #{@dummy.avatar.url}`
+        assert_success_response @dummy.avatar.url
       end
 
       should "be destoryable" do
         url = @dummy.avatar.url
         @dummy.destroy
-        assert_match /404 Not Found/, `curl -I #{url}`
+        assert_not_found_response url
       end
     end
 
@@ -125,17 +125,17 @@ unless ENV["S3_BUCKET"].blank?
       end
 
       should "be accessible" do
-        assert_match /200 OK/, `curl -I "#{@dummy.avatar.url}"`
+        assert_success_response @dummy.avatar.url
       end
 
       should "be accessible with an expiring url" do
-        assert_match /200 OK/, `curl -I "#{@dummy.avatar.expiring_url}"`
+        assert_success_response @dummy.avatar.expiring_url
       end
 
       should "be destroyable" do
         url = @dummy.avatar.url
         @dummy.destroy
-        assert_match /404 Not Found/, `curl -I "#{url}"`
+        assert_not_found_response url
       end
     end
   end