IronRuby.Tests.Tests.MutableString_Length C# (CSharp) Method

        public void MutableString_Length() {
            MutableString x;

            // 0
            x = MutableString.Create("", RubyEncoding.Binary);
            Assert(x.GetCharacterCount() == 0);
           
            x = MutableString.Create("", RubyEncoding.Binary);
            Assert(x.GetCharCount() == 0);

            x = MutableString.Create("", RubyEncoding.Binary);
            Assert(x.GetByteCount() == 0);

            // 1:1:1
            x = MutableString.Create("a", RubyEncoding.Binary);
            Assert(x.GetCharacterCount() == 1);

            x = MutableString.Create("a", RubyEncoding.Binary);
            Assert(x.GetCharCount() == 1);
  
            x = MutableString.Create("a", RubyEncoding.Binary);
            Assert(x.GetByteCount() == 1);

            x = MutableString.Create("a", RubyEncoding.UTF8);
            Assert(x.GetCharacterCount() == 1);

            x = MutableString.Create("a", RubyEncoding.UTF8);
            Assert(x.GetCharCount() == 1);

            x = MutableString.Create("a", RubyEncoding.UTF8);
            Assert(x.GetByteCount() == 1);

            // 1:1:N
            x = MutableString.Create("α", RubyEncoding.UTF8);
            Assert(x.GetCharacterCount() == 1);

            x = MutableString.Create("α", RubyEncoding.UTF8);
            Assert(x.GetCharCount() == 1);

            x = MutableString.Create("α", RubyEncoding.UTF8);
            Assert(x.GetByteCount() == 2);

            x = MutableString.Create("aあa", RubyEncoding.SJIS);
            Assert(x.GetCharacterCount() == 3);

            x = MutableString.Create("aあa", RubyEncoding.SJIS);
            Assert(x.GetCharCount() == 3);

            x = MutableString.Create("aあa", RubyEncoding.SJIS);
            Assert(x.GetByteCount() == RubyEncoding.SJIS.Encoding.GetByteCount("aあa"));

            string s;
            byte[] b;

            // 1:N:N
            s = "\uD820\uDC30";
            b = Encoding.UTF8.GetBytes(s);

            x = MutableString.Create(s, RubyEncoding.UTF8);
            Assert(x.GetCharacterCount() == 1);

            x = MutableString.Create(s, RubyEncoding.UTF8);
            Assert(x.GetCharCount() == 2);

            x = MutableString.Create(s, RubyEncoding.UTF8);
            Assert(x.GetByteCount() == 4);

            x = MutableString.CreateBinary(b, RubyEncoding.UTF8);
            Assert(x.GetCharacterCount() == 1);

            x = MutableString.CreateBinary(b, RubyEncoding.UTF8);
            Assert(x.GetCharCount() == 2);

            x = MutableString.CreateBinary(b, RubyEncoding.UTF8);
            Assert(x.GetByteCount() == 4);

            // surrogate detection tests:
            x = MutableString.Create("a\uD820\uDC30", RubyEncoding.UTF8);
            Assert(x.GetCharacterCount() == 2);

            x = MutableString.Create("\uD820\uDC30a\uD820\uDC30", RubyEncoding.UTF8);
            Assert(x.GetCharacterCount() == 3);

            x = MutableString.Create("\uD820a\uD820\uDC30", RubyEncoding.UTF8);
            Assert(x.GetCharacterCount() == 3);

            x = MutableString.Create("\uD820\uD820\uDC30", RubyEncoding.UTF8);
            Assert(x.GetCharacterCount() == 2);

            x = MutableString.Create("\uD820\uDC30\uDC30", RubyEncoding.UTF8);
            Assert(x.GetCharacterCount() == 2);

            // invalid byte sequences:
            b = new byte[] { 
                0x80,                    // invalid
                0x80,                    // invalid
                (byte)'a', 
                0xEA,                    // invalid
                (byte)'b', 
                0xf0, 0x92, 0x8d, 0x85   // U+12345
            };
            
            x = MutableString.CreateBinary(b, RubyEncoding.UTF8);
            Assert(x.GetCharacterCount() == 6);

            // TODO: throws an exception
            //x = MutableString.CreateBinary(b, RubyEncoding.UTF8);
            //Assert(x.GetCharCount() == 7);

            x = MutableString.CreateBinary(b, RubyEncoding.UTF8);
            Assert(x.GetByteCount() == b.Length);

            // char[] with count < length:
            x = MutableString.CreateMutable("abcd", RubyEncoding.UTF8);
            x.Remove(2, 2);
            Assert(x.GetCharacterCount() == 2);
        }