Merge pull request #285 from dotty-staging/fix/catchNonFatal

Fix/catch non fatal

Author: DarkDimius

src/dotty/tools/dotc/Driver.scala

@@ -4,6 +4,7 @@ import config.CompilerCommand
 import core.Contexts.{Context, ContextBase}
 import util.DotClass
 import reporting._
+import scala.util.control.NonFatal
 
 abstract class Driver extends DotClass {
 
@@ -29,14 +30,9 @@ abstract class Driver extends DotClass {
     try {
       doCompile(newCompiler(), fileNames)
     } catch {
-      case ex: Throwable =>
-        ex match {
-          case ex: FatalError  =>
-            ctx.error(ex.getMessage) // signals that we should fail compilation.
-            ctx.typerState.reporter
-          case _ =>
-            throw ex // unexpected error, tell the outside world.
-        }
+      case ex: FatalError  =>
+        ctx.error(ex.getMessage) // signals that we should fail compilation.
+        ctx.typerState.reporter
     }
   }
 

src/dotty/tools/dotc/core/Denotations.scala

@@ -386,7 +386,7 @@ object Denotations {
         case info: MethodicType =>
           try info.signature
           catch { // !!! DEBUG
-            case ex: Throwable =>
+            case scala.util.control.NonFatal(ex) =>
               println(s"cannot take signature of ${info.show}")
               throw ex
           }

src/dotty/tools/dotc/core/SymbolLoaders.scala

@@ -14,6 +14,7 @@ import Contexts._, Symbols._, Flags._, SymDenotations._, Types._, Scopes._, util
 import StdNames._, NameOps._
 import Decorators.{StringDecorator, StringInterpolators}
 import pickling.ClassfileParser
+import scala.util.control.NonFatal
 
 object SymbolLoaders {
   /** A marker trait for a completer that replaces the original
@@ -206,7 +207,7 @@ abstract class SymbolLoader extends LazyType {
     } catch {
       case ex: IOException =>
         signalError(ex)
-      case ex: Throwable =>
+      case NonFatal(ex) =>
         println(s"exception caught when loading $root: $ex")
         throw ex
     } finally {

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

@@ -12,6 +12,7 @@ import util.{Stats, DotClass, SimpleMap}
 import config.Config
 import config.Printers._
 import TypeErasure.{erasedLub, erasedGlb}
+import scala.util.control.NonFatal
 
 /** Provides methods to compare types.
  */
@@ -401,7 +402,7 @@ class TypeComparer(initctx: Context) extends DotClass {
 
         result
       } catch {
-        case ex: Throwable =>
+        case NonFatal(ex) =>
           def showState =  {
             println(disambiguated(implicit ctx => s"assertion failure for ${tp1.show} <:< ${tp2.show}, frozen = $frozenConstraint"))
             def explainPoly(tp: Type) = tp match {

src/dotty/tools/dotc/core/pickling/ClassfileParser.scala

@@ -13,6 +13,7 @@ import scala.collection.mutable.{ ListBuffer, ArrayBuffer }
 import scala.annotation.switch
 import typer.Checking.checkNonCyclic
 import io.AbstractFile
+import scala.util.control.NonFatal
 
 class ClassfileParser(
     classfile: AbstractFile,
@@ -447,7 +448,7 @@ class ClassfileParser(
     else Some(Annotation.deferredResolve(attrType, argbuf.toList))
   } catch {
     case f: FatalError => throw f // don't eat fatal errors, they mean a class was not found
-    case ex: Throwable =>
+    case NonFatal(ex) =>
       // We want to be robust when annotations are unavailable, so the very least
       // we can do is warn the user about the exception
       // There was a reference to ticket 1135, but that is outdated: a reference to a class not on

src/dotty/tools/dotc/transform/TreeChecker.scala

@@ -23,6 +23,7 @@ import util.SourcePosition
 import collection.mutable
 import ProtoTypes._
 import java.lang.AssertionError
+import scala.util.control.NonFatal
 
 /** Run by -Ycheck option after a given phase, this class retypes all syntax trees
  *  and verifies that the type of each tree node so obtained conforms to the type found in the tree node.
@@ -58,7 +59,7 @@ class TreeChecker {
     val checker = new Checker(previousPhases(phasesToRun.toList)(ctx))
     try checker.typedExpr(ctx.compilationUnit.tpdTree)(checkingCtx)
     catch {
-      case ex: Throwable =>
+      case NonFatal(ex) =>
         implicit val ctx: Context = checkingCtx
         println(i"*** error while checking after phase ${checkingCtx.phase.prev} ***")
         throw ex

src/dotty/tools/dotc/transform/TreeTransform.scala

@@ -16,6 +16,7 @@ import dotty.tools.dotc.core.Decorators._
 import dotty.tools.dotc.util.DotClass
 import scala.annotation.tailrec
 import config.Printers.transforms
+import scala.util.control.NonFatal
 
 object TreeTransforms {
   import tpd._
@@ -1215,6 +1216,8 @@ object TreeTransforms {
           goOther(tree, info.nx.nxTransOther(cur))
       }
 
+    private var crashingTree: Tree = EmptyTree
+
     def transform(tree: Tree, info: TransformerInfo, cur: Int)(implicit ctx: Context): Tree = ctx.traceIndented(s"transforming ${tree.show} at ${ctx.phase}", transforms, show = true) {
       try
         if (cur < info.transformers.length) {
@@ -1228,8 +1231,11 @@ object TreeTransforms {
           }
         } else tree
       catch {
-        case ex: Throwable =>
-          println(i"exception while transforming $tree of class ${tree.getClass} # ${tree.uniqueId}")
+        case NonFatal(ex) =>
+          if (tree ne crashingTree) {
+            crashingTree = tree
+            println(i"exception while transforming $tree of class ${tree.getClass} # ${tree.uniqueId}")
+          }
           throw ex
       }
     }

src/dotty/tools/dotc/typer/Applications.scala

@@ -763,6 +763,12 @@ trait Applications extends Compatibility { self: Typer =>
     }
   }
 
+  /** A typed unapply hook, can be overridden by re any-typers between frontend
+   *  and pattern matcher.
+   */
+  def typedUnApply(tree: untpd.UnApply, selType: Type)(implicit ctx: Context) =
+    throw new UnsupportedOperationException("cannot type check an UnApply node")
+
   /** Is given method reference applicable to type arguments `targs` and argument trees `args`?
    *  @param  resultType   The expected result type of the application
    */

src/dotty/tools/dotc/typer/FrontEnd.scala

@@ -8,6 +8,7 @@ import dotty.tools.dotc.parsing.JavaParsers.JavaParser
 import parsing.Parsers.Parser
 import config.Printers._
 import util.Stats._
+import scala.util.control.NonFatal
 
 class FrontEnd extends Phase {
 
@@ -16,7 +17,7 @@ class FrontEnd extends Phase {
   def monitor(doing: String)(body: => Unit)(implicit ctx: Context) =
     try body
     catch {
-      case ex: Throwable =>
+      case NonFatal(ex) =>
         println(s"exception occured while $doing ${ctx.compilationUnit}")
         throw ex
     }

src/dotty/tools/dotc/typer/ReTyper.scala

@@ -9,6 +9,7 @@ import Decorators._
 import typer.ProtoTypes._
 import ast.{tpd, untpd}
 import ast.Trees._
+import scala.util.control.NonFatal
 
 /** A version of Typer that keeps all symbols defined and referenced in a
  *  previously typed tree.
@@ -91,7 +92,7 @@ class ReTyper extends Typer {
   override def typedUnadapted(tree: untpd.Tree, pt: Type)(implicit ctx: Context) =
     try super.typedUnadapted(tree, pt)
     catch {
-      case ex: Throwable =>
+      case NonFatal(ex) =>
         println(i"exception while typing $tree of class ${tree.getClass} # ${tree.uniqueId}")
         throw ex
     }

src/dotty/tools/dotc/typer/Typer.scala

@@ -1021,6 +1021,7 @@ class Typer extends Namer with TypeAssigner with Applications with Implicits wit
           case tree: untpd.PackageDef => typedPackageDef(tree)
           case tree: untpd.Annotated => typedAnnotated(tree, pt)
           case tree: untpd.TypedSplice => tree.tree
+          case tree:  untpd.UnApply => typedUnApply(tree, pt)
           case untpd.PostfixOp(tree, nme.WILDCARD) => typedAsFunction(tree, pt)
           case untpd.EmptyTree => tpd.EmptyTree
           case _ => typedUnadapted(desugar(tree), pt)