dotty.tools.scaladoc.util.JSON.scala Maven / Gradle / Ivy
package dotty.tools.scaladoc
package util
import scala.annotation.tailrec
opaque type JSON = String
def rawJSON(s: String): JSON = s
def jsonList(elems: Seq[JSON]): JSON = elems.mkString("[", ",\n", "]")
def jsonObject(fields: (String, JSON)*): JSON =
fields.map{ case (k, v) => quoteStr(k)+":"+v}.mkString("{", ",", "}")
def quoteStr(str: String) = s""""$str""""
// based on Spray Json
def jsonString(s: String): JSON =
def requiresEncoding(c: Char): Boolean =
// from RFC 4627
// unescaped = %x20-21 / %x23-5B / %x5D-10FFFF
c match
case '"' => true
case '\\' => true
case c => c < 0x20
val sb = new StringBuilder
@tailrec def firstToBeEncoded(ix: Int = 0): Int =
if (ix == s.length) -1 else if (requiresEncoding(s.charAt(ix))) ix else firstToBeEncoded(ix + 1)
sb.append('"')
firstToBeEncoded() match
case -1 => sb.append(s)
case first =>
// sb.append(s, 0, first) for "abc", 0, 2 produce "(abc,0,2)" rather then "ab" as in Java
sb.append(s.substring(0, first))
@tailrec def append(ix: Int): Unit =
if (ix < s.length) {
s.charAt(ix) match
case c if !requiresEncoding(c) => sb.append(c)
case '"' => sb.append("\\\"")
case '\\' => sb.append("\\\\")
case '\b' => sb.append("\\b")
case '\f' => sb.append("\\f")
case '\n' => sb.append("\\n")
case '\r' => sb.append("\\r")
case '\t' => sb.append("\\t")
case x if x <= 0xF => sb.append("\\u000").append(Integer.toHexString(x))
case x if x <= 0xFF => sb.append("\\u00").append(Integer.toHexString(x))
case x if x <= 0xFFF => sb.append("\\u0").append(Integer.toHexString(x))
case x => sb.append("\\u").append(Integer.toHexString(x))
append(ix + 1)
}
append(first)
sb.append('"').toString