com.sksamuel.scapegoat.inspections.imports.DuplicateImport.scala Maven / Gradle / Ivy

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package com.sksamuel.scapegoat.inspections.imports

import scala.collection.mutable

import com.sksamuel.scapegoat.{Inspection, InspectionContext, Inspector, Levels}

/**
 * @author Stephen Samuel
 */
class DuplicateImport
    extends Inspection(
      text = "Duplicate import",
      defaultLevel = Levels.Info,
      description = "Checks for duplicate import statements.",
      explanation = "Duplicate imports should be removed."
    ) {

  def inspector(context: InspectionContext): Inspector =
    new Inspector(context) {

      private val imports = mutable.HashSet[String]()

      override def postTyperTraverser =
        new context.Traverser {

          import context.global._

          override def inspect(tree: Tree): Unit = {
            tree match {
              case PackageDef(_, _) =>
                imports.clear(); continue(tree)
              case ModuleDef(_, _, _) =>
                imports.clear(); continue(tree)
              case ClassDef(_, _, _, _) =>
                imports.clear(); continue(tree)
              case Import(expr, selectors) =>
                selectors.foreach { selector =>
                  val name = expr.toString + "." + selector.name
                  if (imports.contains(name))
                    context.warn(tree.pos, self)
                  imports.add(name)
                }
              case DefDef(_, _, _, _, _, _) => // check imports inside defs
              case _                        => continue(tree)
            }
          }
        }
    }
}