Move checkMatch into SpaceEngine

... makes it easier to disable one of them.

Author: dwijnand

compiler/src/dotty/tools/dotc/transform/PatternMatcher.scala

@@ -55,8 +55,7 @@ class PatternMatcher extends MiniPhase {
 
       if !inInlinedCode then
         // check exhaustivity and unreachability
-        SpaceEngine.checkExhaustivity(tree)
-        SpaceEngine.checkRedundancy(tree)
+        SpaceEngine.checkMatch(tree)
 
       translated.ensureConforms(matchType)
     }

compiler/src/dotty/tools/dotc/transform/patmat/Space.scala

@@ -876,7 +876,7 @@ object SpaceEngine {
     case _                                          => tp
   })
 
-  def checkExhaustivity(m: Match)(using Context): Unit = if exhaustivityCheckable(m.selector) then trace(i"checkExhaustivity($m)", debug) {
+  def checkExhaustivity(m: Match)(using Context): Unit = trace(i"checkExhaustivity($m)", debug) {
     val selTyp = toUnderlying(m.selector.tpe).dealias
     debug.println(i"selTyp = $selTyp")
 
@@ -899,7 +899,7 @@ object SpaceEngine {
       report.warning(PatternMatchExhaustivity(showSpaces(deduped), m), m.selector)
   }
 
-  private def redundancyCheckable(sel: Tree)(using Context): Boolean =
+  private def reachabilityCheckable(sel: Tree)(using Context): Boolean =
     // Ignore Expr[T] and Type[T] for unreachability as a special case.
     // Quote patterns produce repeated calls to the same unapply method, but with different implicit parameters.
     // Since we assume that repeated calls to the same unapply method overlap
@@ -909,7 +909,7 @@ object SpaceEngine {
     && !sel.tpe.widen.isRef(defn.QuotedExprClass)
     && !sel.tpe.widen.isRef(defn.QuotedTypeClass)
 
-  def checkRedundancy(m: Match)(using Context): Unit = if redundancyCheckable(m.selector) then trace(i"checkRedundancy($m)", debug) {
+  def checkReachability(m: Match)(using Context): Unit = trace(i"checkReachability($m)", debug) {
     val cases = m.cases.toIndexedSeq
 
     val selTyp = toUnderlying(m.selector.tpe).dealias
@@ -961,4 +961,10 @@ object SpaceEngine {
       i += 1
     }
   }
+
+  def checkMatch(m: Match)(using Context): Unit =
+    if exhaustivityCheckable(m.selector) then
+      checkExhaustivity(m)
+    if reachabilityCheckable(m.selector) then
+      checkReachability(m)
 }