SemanticDBHelper.scala

package xsbt

import scala.reflect.NameTransformer
import scala.tools.nsc.Global

object SemanticDBHelper {

  def semanticName[GlobalType <: Global](g: GlobalType)(sym: g.Symbol): String = {
    var b: java.lang.StringBuffer = null

    def loop(size: Int, _sym: g.Symbol): Unit = {
      val symName = _sym.name
      val nSize = symName.length - (if (symName.endsWith(NameTransformer.LOCAL_SUFFIX_STRING)) 1
                                    else 0)
      val prefix =
        if (_sym.isTypeParameter || _sym.isTypeSkolem) "["
        else if (_sym.isParameter) ".("
        else if (_sym.isConstructor) "`"
        else ""

      @inline
      def methodSuffix = {
        (if (_sym.isConstructor) "`(" else "(") +
          _sym.paramss.flatten
            .map { p =>
              if (p.isByNameParam) {
                "=>" + p.tpe.typeArgs.head.nameAndArgsString
              } else if (g.definitions.isRepeatedParamType(p.tpe)) {
                p.tpe.typeArgs.head.nameAndArgsString + "*"
              } else {
                p.tpe.typeSymbol.name
              }
            }
            .mkString(",") +
          ")" + (if (_sym == sym || sym.isConstructor) "." else "")
      }

      val suffix =
        if (_sym.isTypeParameter || _sym.isTypeSkolem) "]"
        else if (_sym.isParameter) ")"
        else if (_sym.hasPackageFlag) "."
        else if (_sym.isClass || _sym.isType) "#"
        else if (_sym.isMethod) methodSuffix
        else "."

      if (_sym.isRoot || _sym.isRootPackage || _sym == g.NoSymbol || _sym.owner.isEmptyPackage || _sym.owner.isEffectiveRoot) {
        val isRoot = _sym.owner.isRoot
        val prePrefix = if (isRoot) "_root_." else "_empty_."
        val capacity = size + nSize + prePrefix.length + prefix.length + suffix.length
        b = new java.lang.StringBuffer(capacity)
        b.append(prePrefix)
      } else {
        val owner =
          if (_sym.isTypeParameter || _sym.isTypeSkolem || _sym.isParameter || _sym.owner.isConstructor)
            _sym.owner
          else _sym.effectiveOwner.enclClass
        loop(size + nSize + prefix.length + suffix.length, owner)
      }
      b.append(prefix)
      b.append(g.chrs, symName.start, nSize)
      b.append(suffix)
      ()
    }

    def isLocal(sym: g.Symbol): Boolean =
      sym.isLocalToBlock || sym.owner.isRefinementClass

    if ((!sym.isTypeParameter && !sym.isParameter &&
        sym.ownersIterator.exists(isLocal)) || sym.hasPackageFlag) {
      "" // local definition
    } else {
      loop(0, sym)
      b.toString
    }

  }

}