use nullType for simplicity

liufengyun · liufengyun · commit 9e2c8beda14b · 2018-04-05T20:19:44.000+02:00
diff --git a/compiler/src/dotty/tools/dotc/transform/patmat/Space.scala b/compiler/src/dotty/tools/dotc/transform/patmat/Space.scala
@@ -951,7 +951,7 @@ class SpaceEngine(implicit ctx: Context) extends SpaceLogic {
         // if last case is `_` and only matches `null`, produce a warning
         if (i == cases.length - 1 && !isNull(pat) ) {
           simplify(minus(covered, prevs)) match {
-            case Typ(ConstantType(Constant(null)), _) =>
+            case Typ(`nullType`, _) =>
               ctx.warning(MatchCaseOnlyNullWarning(), pat.pos)
             case _ =>
           }

Original file line number	Diff line number	Diff line change
`@@ -951,7 +951,7 @@ class SpaceEngine(implicit ctx: Context) extends SpaceLogic {`
`951`	`951`	// if last case is `_` and only matches `null`, produce a warning
`952`	`952`	`if (i == cases.length - 1 && !isNull(pat) ) {`
`953`	`953`	`simplify(minus(covered, prevs)) match {`
`954`		`- case Typ(ConstantType(Constant(null)), _) =>`
	`954`	+ case Typ(`nullType`, _) =>
`955`	`955`	`ctx.warning(MatchCaseOnlyNullWarning(), pat.pos)`
`956`	`956`	`case _ =>`
`957`	`957`	`}`