org.wartremover.warts.RedundantConversions.scala Maven / Gradle / Ivy
The newest version!
package org.wartremover
package warts
import scala.annotation.nowarn
object RedundantConversions extends WartTraverser {
@nowarn("msg=Stream")
override def apply(u: WartUniverse): u.Traverser = {
import u.universe._
val anyValValues: Map[Name, (String, Type)] = Seq(
"toInt" -> typeOf[Int],
"toLong" -> typeOf[Long],
"toFloat" -> typeOf[Float],
"toDouble" -> typeOf[Double],
"toByte" -> typeOf[Byte],
"toShort" -> typeOf[Short],
"toChar" -> typeOf[Char],
).map { case (name, tpe) =>
TermName(name) -> Tuple2(name, tpe)
}.toMap
val collectionValues: Map[Name, (String, Type)] = Seq(
"toList" -> typeOf[List[Any]],
"toSeq" -> typeOf[collection.immutable.Seq[Any]],
"toVector" -> typeOf[Vector[Any]],
"toSet" -> typeOf[Set[Any]],
"toStream" -> typeOf[Stream[Any]],
"toIndexedSeq" -> typeOf[collection.immutable.IndexedSeq[Any]]
).map { case (name, tpe) =>
TermName(name) -> Tuple2(name, tpe)
}.toMap
new Traverser {
override def traverse(tree: Tree): Unit = {
tree match {
case t if hasWartAnnotation(u)(t) =>
case Select(obj, TermName("toString")) if obj.tpe <:< typeOf[String] =>
error(u)(tree.pos, "redundant toString conversion")
case Select(obj, method) =>
collectionValues.get(method) match {
case Some((name, tpe)) if obj.tpe.typeConstructor <:< tpe.typeConstructor =>
error(u)(tree.pos, s"redundant ${name} conversion")
case _ =>
anyValValues.get(method) match {
case Some((name, tpe)) if obj.tpe =:= tpe =>
error(u)(tree.pos, s"redundant ${name} conversion")
case _ =>
super.traverse(tree)
}
}
case _ =>
super.traverse(tree)
}
}
}
}
}