SimpleArrayUtils.fromString results JsonParseException when string contains new line escape

The following code results JsonParseException: Unrecognized character escape ‘w’

val s = """{"{\"title\": \"hello\\nworld\"}"}"""
utils.SimpleArrayUtils.fromString[JsValue](Json.parse)(s).orNull

[alexandervanhecke]

for future reference, the problem seems to be in the PgTokenHelper.getString method. I first tried manipulating the Tokens returned by PgTokenHelper.Tokenizer.tokenize myself, quickly realised I needed the PgTokenHelper.groupingas well and ended up with this :

    import com.github.tminglei.slickpg.utils.PgTokenHelper._

    def tokenToString(token: Seq[Token]): String =
      token.collect {
        case GroupToken(members) => tokenToString(members)
        case t => t.value
      }.mkString("")

    def fromString[T](convert: String => T)(arrString: String): Option[Seq[T]] =
      grouping(Tokenizer.tokenize(arrString)) match {
        case Null => None
        case root => Some(getChildren(root).map {
          case GroupToken(members) => convert(StringEscapeUtils.unescapeJson(tokenToString(members.drop(1).dropRight(1))))
          case _  => null.asInstanceOf[T]
        })
      }

    implicit val playJsonArrayTypeMapper =
      new AdvancedArrayJdbcType[JsValue](pgjson,
        s => fromString[JsValue](Json.parse)(s).orNull,
        v => utils.SimpleArrayUtils.mkString[JsValue](_.toString())(v)).to(_.toList)

the actual unescaping is done using commons-text StringEscapeUtils. My fromString is basically a copy paste of the SimpleArrayUtils.fromStringreplacing the getString call with an unescapeJson call. This seems to works ok for all kinds of escaped json text inside JSON values.

[zgrannan]

I encountered this error myself. Here is a problematic json value:

"hello \\n world"

This represents hello + a literal backslash + n world, NOT a newline.

When stored in a jsonb column this is no problem, but if it is an element of a jsonb[] array it is incorrectly parsed as:

"hello \\ world"

I have included a failing test case on my branch here: https://github.com/zgrannan/slick-pg/commit/4543de1b9a7c63836a048a59598255e66a0d8405

FYI as a workaround, one can change their db’s jsonb[] column to a json column and convert the data using array_to_json