NoElse.scala

import scalafix.Diagnostic
import scalafix.Patch
import scalafix.lint.LintSeverity
import scalafix.v1.SyntacticDocument
import scalafix.v1.SyntacticRule
import scala.meta.Lit
import scala.meta.Term
import scala.meta.inputs.Position

class NoElse extends SyntacticRule("NoElse") {
  override def fix(implicit doc: SyntacticDocument): Patch = {
    doc.tree.collect {
      case t @ Term.If(_, _, Lit.Unit()) =>
        Patch.lint(
          NoElseWarn(t.pos)
        )
    }.asPatch
  }
}

case class NoElseWarn(override val position: Position) extends Diagnostic {
  override def message = "ifに対してelseがありません"
  override def severity = LintSeverity.Warning
}