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

        public void MutableString_GetHashCode() {
            int h1, h2, h3;
            MutableString s;

            // invalid byte sequence:
            s = MutableString.CreateBinary(new byte[] { 0xce }, RubyEncoding.UTF8);
            h1 = s.GetHashCode();
            Assert(s.GetCharacterCount() == 1);
            h2 = s.GetHashCode();
            Assert(h1 == h2);

            // binary -> string:
            s = MutableString.CreateBinary(new byte[] { 0xce, 0xa3 }, RubyEncoding.UTF8);
            h1 = s.GetHashCode();
            Assert(s.GetCharCount() == 1);
            h2 = s.GetHashCode();
            Assert(s.GetCharacterCount() == 1);
            h3 = s.GetHashCode();
            Assert(h1 == h2);
            Assert(h1 == h3);

            // string -> binary:
            s = MutableString.Create("Σ", RubyEncoding.UTF8);
            h1 = s.GetHashCode();
            Assert(s.GetByteCount() == 2);
            h2 = s.GetHashCode();
            Assert(h1 == h2);

            // string vs. char[] vs CLR string:
            s = MutableString.CreateMutable("Σ", RubyEncoding.UTF8);
            h2 = s.GetHashCode();
            Assert(h1 == h2);
            Assert(h2 == "Σ".GetHashCode());

            // hash(binary) == hash(string):
            s = MutableString.CreateBinary(new byte[] { 0xce, 0xa3 }, RubyEncoding.UTF8);
            h1 = s.GetHashCode();
            s = MutableString.Create("Σ", RubyEncoding.UTF8);
            h2 = s.GetHashCode();
            Assert(h1 == h2);

            // same content, different capacities:
            var a = MutableString.CreateMutable(10, RubyEncoding.UTF8).Append("hello");
            var b = MutableString.CreateMutable(20, RubyEncoding.UTF8).Append("hello");
            var c = MutableString.Create("hello", RubyEncoding.UTF8);
            Assert(a.GetHashCode() == b.GetHashCode());
            Assert(a.GetHashCode() == c.GetHashCode());

            // same content, different encodings:
            // ASCII characters only:
            a = MutableString.Create("hello", RubyEncoding.UTF8);
            b = MutableString.Create("hello", RubyEncoding.SJIS);
            c = MutableString.CreateAscii("hello");
            Assert(a.GetHashCode() == b.GetHashCode());
            Assert(a.GetHashCode() == c.GetHashCode());
            Assert(b.GetHashCode() == c.GetHashCode());

            // TODO: do we need this property?
            // non-ASCII characters:
            // a = MutableString.Create("α", RubyEncoding.UTF8);
            // b = MutableString.Create("α", RubyEncoding.SJIS);
            // c = MutableString.CreateBinary(Encoding.UTF8.GetBytes("α"), RubyEncoding.Binary);
            // Assert(a.GetHashCode() != b.GetHashCode());
            // Assert(a.GetHashCode() != c.GetHashCode());
            // Assert(b.GetHashCode() != c.GetHashCode());
        }