Make sure compilation yields a state with a new Run

Author: felixmulder

repl/src/dotty/tools/repl/ReplCompiler.scala

@@ -155,9 +155,9 @@ class ReplCompiler(val directory: AbstractFile) extends Compiler {
     PackageDef(Ident(nme.EMPTY_PACKAGE), module)
   }
 
-  def newRun(state: State, initCtx: Context) = new Run(this, initCtx) {
+  def newRun(initCtx: Context, objectIndex: Int) = new Run(this, initCtx) {
     override protected[this] def rootContext(implicit ctx: Context) =
-      addMagicImports(super.rootContext.fresh.setReporter(storeReporter), state)
+      addMagicImports(super.rootContext.fresh.setReporter(storeReporter), objectIndex)
   }
 
   def createUnit(defs: Definitions, sourceCode: String): Result[CompilationUnit] = {
@@ -183,7 +183,7 @@ class ReplCompiler(val directory: AbstractFile) extends Compiler {
     } yield (unit, state)
   }
 
-  private[this] def addMagicImports(initCtx: Context, state: State): Context = {
+  private[this] def addMagicImports(initCtx: Context, objectIndex: Int): Context = {
     def addImport(path: TermName)(implicit ctx: Context) = {
       val ref = tpd.ref(ctx.requiredModuleRef(path.toTermName))
       val symbol = ctx.newImportSymbol(ctx.owner, ref)
@@ -193,7 +193,7 @@ class ReplCompiler(val directory: AbstractFile) extends Compiler {
     }
 
     List
-      .range(1, state.objectIndex + 1)
+      .range(1, objectIndex + 1)
       .foldLeft(addImport("dotty.Show".toTermName)(initCtx)) { (ictx, i) =>
         addImport(nme.EMPTY_PACKAGE ++ "." ++ objectNames(i))(ictx)
       }

repl/src/dotty/tools/repl/ReplDriver.scala

@@ -64,7 +64,7 @@ case class State(objectIndex: Int,
   def withHistory(h: History) = copy(history = h)
 
   def newRun(comp: ReplCompiler, rootCtx: Context): State =
-    copy(run = comp.newRun(this, rootCtx))
+    copy(run = comp.newRun(rootCtx, objectIndex))
 }
 
 /** A list of possible completions at the index of `cursor`
@@ -93,7 +93,7 @@ class ReplDriver(settings: Array[String], protected val out: PrintStream = Syste
   }
 
   /** the initial, empty state of the REPL session */
-  protected[this] def initState = State(0, 0, Nil, Nil, compiler.newRun(rootCtx))
+  protected[this] def initState = State(0, 0, Nil, Nil, compiler.newRun(rootCtx, 0))
 
   /** Reset state of repl to the initial state
    *
@@ -139,10 +139,8 @@ class ReplDriver(settings: Array[String], protected val out: PrintStream = Syste
     }
   }
 
-  final def run(input: String)(implicit state: State): State = {
-    val freshState = state.newRun(compiler, rootCtx)
-    run(ParseResult(input)(freshState.run.runContext))(freshState)
-  }
+  final def run(input: String)(implicit state: State): State =
+    run(ParseResult(input)(state.run.runContext))(state.newRun(compiler, rootCtx))
 
   final def run(res: ParseResult)(implicit state: State): State =
     interpret(res)
@@ -184,7 +182,9 @@ class ReplDriver(settings: Array[String], protected val out: PrintStream = Syste
   private def interpret(res: ParseResult)(implicit state: State): State =
     res match {
       case parsed: Parsed =>
-        compile(parsed).withHistory(parsed.sourceCode :: state.history)
+        compile(parsed)
+          .withHistory(parsed.sourceCode :: state.history)
+          .newRun(compiler, rootCtx)
 
       case SyntaxErrors(src, errs, _) =>
         displayErrors(errs)

repl/test-resources/repl/errorThenValid

@@ -0,0 +1,6 @@
+scala> val xs = scala.collection.mutable.ListBuffer[Int]
+1 | val xs = scala.collection.mutable.ListBuffer[Int]
+  |          ^
+  |          missing parameter type for parameter elems, expected = ?
+scala> val xs = scala.collection.mutable.ListBuffer[Int]()
+val xs: scala.collection.mutable.ListBuffer[Int] = ListBuffer()