Round trip through utf-16 to clean utf-8 string

As noted in the ruby docs (http://ruby-doc.org/core-1.9.3/String.html#method-i-encode),
any conversion from an encoding to the same encoding is a no-op, covert it first to utf-16.

2 files changed, 12 insertions, 9 deletions

diff --git a/lib/normalize_string.rb b/lib/normalize_string.rb
index d850d7e05..8b54c080c 100644
--- a/lib/normalize_string.rb
+++ b/lib/normalize_string.rb
@@ -77,16 +77,20 @@ def convert_string_to_utf8(s, suggested_character_encoding=nil)
     begin
         result = normalize_string_to_utf8 s, suggested_character_encoding
     rescue EncodingNormalizationError
-        result = s
-        if String.method_defined?(:encode)
-            result = s.force_encoding("utf-8").encode("utf-8", :invalid => :replace,
-                                                               :undef => :replace,
-                                                               :replace => "")
-        end
+        result = scrub(s)
     end
     result
 end
 
+def scrub(string)
+    if String.method_defined?(:encode)
+        string = string.force_encoding("utf-8")
+        string.valid_encoding? ? string : string.encode("utf-16le", :invalid => :replace, :replace => "").encode("utf-8")
+    else
+        Iconv.conv('UTF-8//IGNORE', 'UTF-8', string)
+    end
+end
+
 def log_text_details(message, text)
     if String.method_defined?(:encode)
         STDERR.puts "#{message}, we have text: #{text}, of class #{text.class} and encoding #{text.encoding}"
diff --git a/spec/lib/basic_encoding_spec.rb b/spec/lib/basic_encoding_spec.rb
index d77465ad8..d802da892 100644
--- a/spec/lib/basic_encoding_spec.rb
+++ b/spec/lib/basic_encoding_spec.rb
@@ -160,17 +160,16 @@ describe "convert_string_to_utf8" do
 
     describe "when passed uninterpretable character data" do
 
-        it "should return it as a utf8 string" do
+        it "should return it as a valid utf8 string with non-utf8 characters removed" do
 
             converted = convert_string_to_utf8 random_string
-            converted.should == random_string
 
             if String.method_defined?(:encode)
                 converted.encoding.to_s.should == 'UTF-8'
+                converted.valid_encoding?.should == true
             end
 
             converted = convert_string_to_utf8 random_string,'UTF-8'
-            converted.should == random_string
 
             if String.method_defined?(:encode)
                 converted.encoding.to_s.should == 'UTF-8'