can't deserialize string ending with backslash

[vilinski]

Repro - add this to tests/Utf8Json.Tests/StringEscapeTest.cs

            str = "\"\\\"";
            JsonSerializer.Deserialize<string>(str).Is("\\");

the string, containing a single backslash can't be deserialized. The same bug is also reproducebla for other strings with a backslash at end.

[RamType0]

Utf8Json/src/Utf8Json/JsonReader.cs

Lines 754 to 791 in 608cf01

	public ArraySegment<byte> ReadStringSegmentRaw()
	{
	ArraySegment<byte> key = default(ArraySegment<byte>);
	if (ReadIsNull())
	{
	key = nullTokenSegment;
	}
	else
	{
	// SkipWhiteSpace is already called from IsNull
	if (bytes[offset++] != '\"') throw CreateParsingException("\"");
	var from = offset;
	for (int i = offset; i < bytes.Length; i++)
	{
	if (bytes[i] == (char)'\"')
	{
	// is escape?
	if (bytes[i - 1] == (char)'\\')
	{
	continue;
	}
	else
	{
	offset = i + 1;
	goto OK;
	}
	}
	}
	throw CreateParsingExceptionMessage("not found end string.");
	OK:
	key = new ArraySegment<byte>(bytes, from, offset - from - 1); // remove \"
	}
	return key;
	}

Maybe this code is causing this bug.
This code works on policy like "Find first double quote,but if it is leaded by backslash,it is not a end of string.Otherwise,it is a end of string"
This policy doesn't work well in case of this.

[RamType0]

#220
I made this pull request.
Actually,your issue was not correct.
You need "\"\\\\\"" for representing single backslash on Json.
But it was useful to find another issue.Thanks!

[vilinski]

Cool, hope it will be merged