Enable explicit nulls for all compile

Author: noti0na1

compiler/src/dotty/tools/dotc/core/TypeComparer.scala

@@ -2126,11 +2126,12 @@ class TypeComparer(@constructorOnly initctx: Context) extends ConstraintHandling
                 if (hi1 & hi2).isEmpty then return orType(tp1, tp2)
               case none =>
           case none =>
+            
         val t1 = mergeIfSuper(tp1, tp2, canConstrain)
-        if (t1.exists) return t1
+        if t1.exists then return t1.simplified
 
         val t2 = mergeIfSuper(tp2, tp1, canConstrain)
-        if (t2.exists) return t2
+        if t2.exists then return t2.simplified
 
         def widen(tp: Type) = if (widenInUnions) tp.widen else tp.widenIfUnstable
         val tp1w = widen(tp1)

compiler/src/dotty/tools/dotc/util/ClasspathFromClassloader.scala

@@ -14,7 +14,7 @@ object ClasspathFromClassloader {
    *  BEWARE: with exotic enough classloaders, this may not work at all or do
    *  the wrong thing.
    */
-  def apply(cl: ClassLoader): String = {
+  def apply(cl: ClassLoader | Null): String = {
     val classpathBuff = List.newBuilder[String]
     def collectClassLoaderPaths(cl: ClassLoader): Unit = {
       if (cl != null) {

compiler/src/dotty/tools/dotc/util/GenericHashMap.scala

@@ -133,7 +133,7 @@ abstract class GenericHashMap[Key, Value]
       val v1 = value
       v = v1
       update(key, v1)
-    v.uncheckedNN
+    v
 
   private def addOld(key: Key, value: Value): Unit =
     Stats.record(statsItem("re-enter"))

compiler/src/dotty/tools/dotc/util/HashSet.scala

@@ -84,7 +84,7 @@ class HashSet[T](initialCapacity: Int = 8, capacityMultiple: Int = 2) extends Mu
     var idx = firstIndex(x)
     var e: T | Null = entryAt(idx)
     while e != null do
-      if isEqual(e.uncheckedNN, x) then return e
+      if isEqual(e, x) then return e
       idx = nextIndex(idx)
       e = entryAt(idx)
     null
@@ -102,8 +102,7 @@ class HashSet[T](initialCapacity: Int = 8, capacityMultiple: Int = 2) extends Mu
     var idx = firstIndex(x)
     var e: T | Null = entryAt(idx)
     while e != null do
-      // TODO: remove uncheckedNN when explicit-nulls is enabled for regule compiling
-      if isEqual(e.uncheckedNN, x) then return e.uncheckedNN
+      if isEqual(e, x) then return e
       idx = nextIndex(idx)
       e = entryAt(idx)
     addEntryAt(idx, x)
@@ -115,20 +114,20 @@ class HashSet[T](initialCapacity: Int = 8, capacityMultiple: Int = 2) extends Mu
     var idx = firstIndex(x)
     var e: T | Null = entryAt(idx)
     while e != null do
-      if isEqual(e.uncheckedNN, x) then
+      if isEqual(e, x) then
         var hole = idx
         while
           idx = nextIndex(idx)
           e = entryAt(idx)
           e != null
         do
-          val eidx = index(hash(e.uncheckedNN))
+          val eidx = index(hash(e))
           if isDense
             || index(eidx - (hole + 1)) > index(idx - (hole + 1))
                // entry `e` at `idx` can move unless `index(hash(e))` is in
                // the (ring-)interval [hole + 1 .. idx]
           then
-            setEntry(hole, e.uncheckedNN)
+            setEntry(hole, e)
             hole = idx
         table(hole) = null
         used -= 1
@@ -156,7 +155,7 @@ class HashSet[T](initialCapacity: Int = 8, capacityMultiple: Int = 2) extends Mu
       var idx = 0
       while idx < oldTable.length do
         val e: T | Null = oldTable(idx).asInstanceOf[T | Null]
-        if e != null then addOld(e.uncheckedNN)
+        if e != null then addOld(e)
         idx += 1
 
   protected def growTable(): Unit =

compiler/src/dotty/tools/dotc/util/ReadOnlyMap.scala

@@ -15,19 +15,25 @@ abstract class ReadOnlyMap[Key, Value]:
 
   def isEmpty: Boolean = size == 0
 
-  def get(key: Key): Option[Value] = lookup(key) match
-    case null => None
-    case v => Some(v.uncheckedNN)
-
-  def getOrElse(key: Key, value: => Value) = lookup(key) match
-    case null => value
-    case v => v.uncheckedNN
+  def get(key: Key): Option[Value] = 
+    val v = lookup(key) 
+    v match
+      case null => None
+      case _ => Some(v)
+
+  def getOrElse(key: Key, value: => Value) = 
+    val v = lookup(key) 
+    v match
+      case null => value
+      case _ => v
 
   def contains(key: Key): Boolean = lookup(key) != null
 
-  def apply(key: Key): Value = lookup(key) match
-    case null => throw new NoSuchElementException(s"$key")
-    case v => v.uncheckedNN
+  def apply(key: Key): Value = 
+    val v = lookup(key) 
+    v match
+      case null => throw new NoSuchElementException(s"$key")
+      case _ => v
 
   def toArray: Array[(Key, Value)] =
     val result = new Array[(Key, Value)](size)

compiler/src/dotty/tools/dotc/util/WeakHashSet.scala

@@ -178,7 +178,7 @@ abstract class WeakHashSet[A <: AnyRef](initialCapacity: Int = 8, loadFactor: Do
         case null                    => addEntryAt(bucket, elem, h, oldHead)
         case _                       =>
           val entryElem = entry.get
-          if entryElem != null && isEqual(elem, entryElem) then entryElem.uncheckedNN
+          if entryElem != null && isEqual(elem, entryElem) then entryElem
           else linkedListLoop(entry.tail)
       }
 

compiler/test/dotty/tools/dotc/TastyBootstrapTests.scala

@@ -50,7 +50,7 @@ class TastyBootstrapTests {
         Properties.compilerInterface, Properties.scalaLibrary, Properties.scalaAsm,
         Properties.dottyInterfaces, Properties.jlineTerminal, Properties.jlineReader,
       ).mkString(File.pathSeparator),
-      Array("-Ycheck-reentrant", "-language:postfixOps", "-Xsemanticdb")
+      Array("-Ycheck-reentrant", "-language:postfixOps", "-Xsemanticdb", "-Yexplicit-nulls")
     )
 
     val libraryDirs = List(Paths.get("library/src"), Paths.get("library/src-bootstrapped"))

compiler/test/dotty/tools/vulpix/TestConfiguration.scala

@@ -66,7 +66,7 @@ object TestConfiguration {
   val defaultOptions = TestFlags(basicClasspath, commonOptions)
   val unindentOptions = TestFlags(basicClasspath, Array("-no-indent") ++ checkOptions ++ noCheckOptions ++ yCheckOptions)
   val withCompilerOptions =
-    defaultOptions.withClasspath(withCompilerClasspath).withRunClasspath(withCompilerClasspath)
+    defaultOptions.withClasspath(withCompilerClasspath).withRunClasspath(withCompilerClasspath) and "-Yexplicit-nulls"
   lazy val withStagingOptions =
     defaultOptions.withClasspath(withStagingClasspath).withRunClasspath(withStagingClasspath)
   lazy val withTastyInspectorOptions =
@@ -82,7 +82,7 @@ object TestConfiguration {
     "-Yprint-pos-syms"
   )
   val picklingWithCompilerOptions =
-    picklingOptions.withClasspath(withCompilerClasspath).withRunClasspath(withCompilerClasspath)
+    picklingOptions.withClasspath(withCompilerClasspath).withRunClasspath(withCompilerClasspath) and "-Yexplicit-nulls"
   val scala2CompatMode = defaultOptions.and("-source", "3.0-migration")
   val explicitUTF8 = defaultOptions and ("-encoding", "UTF8")
   val explicitUTF16 = defaultOptions and ("-encoding", "UTF16")

project/Build.scala

@@ -611,6 +611,9 @@ object Build {
 
       Compile / mainClass := Some("dotty.tools.dotc.Main"),
 
+      // Note: bench/profiles/projects.yml should be updated accordingly.
+      Compile / scalacOptions ++= Seq("-Yexplicit-nulls"),
+
       scala := {
         val args: List[String] = spaceDelimited("<arg>").parsed.toList
         val externalDeps = externalCompilerClasspathTask.value
@@ -773,9 +776,6 @@ object Build {
       )
     },
 
-    // Note: bench/profiles/projects.yml should be updated accordingly.
-    Compile / scalacOptions ++= Seq("-Yexplicit-nulls"),
-
     repl := (Compile / console).value,
     Compile / console / scalacOptions := Nil, // reset so that we get stock REPL behaviour!  E.g. avoid -unchecked being enabled
   )

tests/neg-with-compiler/GenericNumLits/EvenFromDigitsImpl_1.scala

@@ -10,7 +10,7 @@ object EvenFromDigitsImpl:
         try evenFromDigits(ds)
         catch {
           case ex: FromDigits.FromDigitsException =>
-            quotes.reflect.report.error(ex.getMessage)
+            quotes.reflect.report.error(ex.getMessage.nn)
             Even(0)
         }
       '{Even(${Expr(ev.n)})}

tests/pos-with-compiler/Fileish.scala

@@ -19,7 +19,7 @@ class Fileish(val path: Path, val input: () => InputStream) extends Streamable.C
 
   private lazy val pkgLines = lines() collect { case x if x startsWith "package " => x stripPrefix "package" trim }
   lazy val pkgFromPath      = parent.path.replaceAll("""[/\\]""", ".")
-  lazy val pkgFromSource    = pkgLines map (_ stripSuffix ";") mkString "."
+  lazy val pkgFromSource    = pkgLines map (_.nn.stripSuffix(";")) mkString "."
 
   override def toString = path.path
 }
@@ -32,7 +32,7 @@ class Fileish2(val path: Path, val input: () => InputStream) extends Streamable.
 
   private val pkgLines = lines() collect { case x if x startsWith "package " => x stripPrefix "package" trim }
   lazy val pkgFromPath      = parent.path.replaceAll("""[/\\]""", ".")
-  lazy val pkgFromSource    = pkgLines map (_ stripSuffix ";") mkString "."
+  lazy val pkgFromSource    = pkgLines map (_.nn.stripSuffix(";")) mkString "."
 
   override def toString = path.path
 }
@@ -46,7 +46,7 @@ class Fileish3(val path: Path, val input: () => InputStream) extends Streamable.
 
   private val pkgLines = lines() collect { case x if x startsWith "package " => x stripPrefix "package" trim }
   private val pkgFromPath      = parent.path.replaceAll("""[/\\]""", ".")
-  private val pkgFromSource    = pkgLines map (_ stripSuffix ";") mkString "."
+  private val pkgFromSource    = pkgLines map (_.nn.stripSuffix(";")) mkString "."
 
   override def toString = path.path
 }

tests/pos-with-compiler/Patterns.scala

@@ -2,7 +2,7 @@ import dotty.tools.dotc.ast.Trees.*
 import dotty.tools.dotc.core.Types.*
 
 object Patterns {
-  val d: Object = null
+  val d: Object = null.asInstanceOf[Object]
   private def rebase(tp: NamedType): Type = {
     def rebaseFrom(prefix: Type): Type = ???
     tp.prefix match {

tests/pos-with-compiler/benchSets.scala

@@ -78,7 +78,7 @@ def testAnyRefMap =
       i += 1
     while i > 0 do
       i -= 1
-      val v = set.getOrNull(elems(i))
+      val v: Elem | Null = set.getOrNull(elems(i))
       if v != null then
         count += 1
     iter += 1

tests/pos-with-compiler/lazyValsSepComp.scala

@@ -10,7 +10,7 @@ import dotty.tools.dotc.core.Contexts.*
 
 /** A test to trigger issue with separate compilation and lazy vals */
 object Foo {
-  val definitions: Definitions = null
+  val definitions: Definitions = null.asInstanceOf[Definitions]
   def defn = definitions
   def go = defn.ScalaBoxedClasses
 }

tests/run-with-compiler/i14541.scala

@@ -4,7 +4,7 @@ object Test:
   import dotty.tools.runner.RichClassLoader.*
   val classpath = dotty.tools.dotc.util.ClasspathFromClassloader(getClass.getClassLoader)
   def main(args: Array[String]): Unit =
-    getClass.getClassLoader.run("echo", List("hello", "raw", "world"))
+    getClass.getClassLoader.nn.run("echo", List("hello", "raw", "world"))
     // caution: uses "SCALA_OPTS"
     dotty.tools.MainGenericRunner.main(Array("--class-path", classpath, "echo", "hello", "run", "world"))
 

tests/run-with-compiler/scripting.scala

@@ -1,7 +1,7 @@
 object Test {
   def main(args: Array[String]): Unit = {
     val m = new javax.script.ScriptEngineManager(getClass().getClassLoader())
-    val e = m.getEngineByName("scala")
+    val e = m.getEngineByName("scala").nn
     println(e.eval("42"))
     println(e.eval("Some(42)").asInstanceOf[Option[Int]].get)
     println(e.eval(new java.io.StringReader("42")))