From 7fa78597bf58a7759303095121a432cb258f447c Mon Sep 17 00:00:00 2001 From: Martin Odersky Date: Mon, 10 Mar 2014 17:48:55 +0100 Subject: Fix problems related to t0039 This test case exercised several problems: 1.)2.) Two ways to run into a cyclic references. Fixed by - assuming an early info when completing a typedef, similarly to what is done for a classdef - doing wellformed bounds checking in a later phase. Failure to check whether arguments correspond to F-bounds. - a substitution was missing. --- src/dotty/tools/dotc/core/Flags.scala | 2 +- src/dotty/tools/dotc/core/SymDenotations.scala | 11 ++++++++--- src/dotty/tools/dotc/typer/Checking.scala | 7 +++++-- src/dotty/tools/dotc/typer/Namer.scala | 1 + src/dotty/tools/dotc/typer/Typer.scala | 5 +++-- tests/new/t0039.scala | 6 ++++++ 6 files changed, 24 insertions(+), 8 deletions(-) create mode 100644 tests/new/t0039.scala diff --git a/src/dotty/tools/dotc/core/Flags.scala b/src/dotty/tools/dotc/core/Flags.scala index 0678b79be..620cd4fa5 100644 --- a/src/dotty/tools/dotc/core/Flags.scala +++ b/src/dotty/tools/dotc/core/Flags.scala @@ -467,7 +467,7 @@ object Flags { final val ExpandedTypeParam = allOf(ExpandedName, TypeParam) /** A parameter or parameter accessor */ - final val ParamOrAccessor = Param | Accessor + final val ParamOrAccessor = Param | ParamAccessor /** A covariant type parameter instance */ final val LocalCovariant = allOf(Local, Covariant) diff --git a/src/dotty/tools/dotc/core/SymDenotations.scala b/src/dotty/tools/dotc/core/SymDenotations.scala index 5fbf6c2c4..bbe5cf986 100644 --- a/src/dotty/tools/dotc/core/SymDenotations.scala +++ b/src/dotty/tools/dotc/core/SymDenotations.scala @@ -145,9 +145,14 @@ object SymDenotations { if (myFlags is Touched) throw new CyclicReference(this) myFlags |= Touched - completions.println(s"completing ${this.debugString}") - completer.complete(this) - completions.println(s"completed ${this.debugString}") + // completions.println(s"completing ${this.debugString}") + try completer.complete(this) + catch { + case ex: CyclicReference => + completions.println(s"error while completing ${this.debugString}") + throw ex + } + // completions.println(s"completed ${this.debugString}") } protected[dotc] final def info_=(tp: Type) = { diff --git a/src/dotty/tools/dotc/typer/Checking.scala b/src/dotty/tools/dotc/typer/Checking.scala index 25e6a7aa7..e3024b9a6 100644 --- a/src/dotty/tools/dotc/typer/Checking.scala +++ b/src/dotty/tools/dotc/typer/Checking.scala @@ -45,13 +45,16 @@ trait Checking extends NoChecking { } /** Check that type arguments `args` conform to corresponding bounds in `poly` */ - override def checkBounds(args: List[tpd.Tree], poly: PolyType, pos: Position)(implicit ctx: Context): Unit = + override def checkBounds(args: List[tpd.Tree], poly: PolyType, pos: Position)(implicit ctx: Context): Unit = { + val argTypes = args.tpes + def substituted(tp: Type) = tp.substParams(poly, argTypes) for ((arg, bounds) <- args zip poly.paramBounds) { def notConforms(which: String, bound: Type) = ctx.error(i"Type argument ${arg.tpe} does not conform to $which bound $bound", arg.pos) - if (!(arg.tpe <:< bounds.hi)) notConforms("upper", bounds.hi) + if (!(arg.tpe <:< substituted(bounds.hi))) notConforms("upper", bounds.hi) if (!(bounds.lo <:< arg.tpe)) notConforms("lower", bounds.lo) } + } /** Check that type `tp` is stable. * @return The type itself diff --git a/src/dotty/tools/dotc/typer/Namer.scala b/src/dotty/tools/dotc/typer/Namer.scala index c24021936..9c8522b83 100644 --- a/src/dotty/tools/dotc/typer/Namer.scala +++ b/src/dotty/tools/dotc/typer/Namer.scala @@ -614,6 +614,7 @@ class Namer { typer: Typer => def typeDefSig(tdef: TypeDef, sym: Symbol)(implicit ctx: Context): Type = { completeParams(tdef.tparams) + sym.info = TypeBounds.empty // avoid cyclic reference errors for F-bounds val tparamSyms = tdef.tparams map symbolOfTree val rhsType = typedAheadType(tdef.rhs).tpe diff --git a/src/dotty/tools/dotc/typer/Typer.scala b/src/dotty/tools/dotc/typer/Typer.scala index 6a1d279df..e195c2807 100644 --- a/src/dotty/tools/dotc/typer/Typer.scala +++ b/src/dotty/tools/dotc/typer/Typer.scala @@ -699,8 +699,9 @@ class Typer extends Namer with TypeAssigner with Applications with Implicits wit val TypeBoundsTree(lo, hi) = desugar.typeBoundsTree(tree) val lo1 = typed(lo) val hi1 = typed(hi) - if (!(lo1.tpe <:< hi1.tpe)) - ctx.error(i"lower bound ${lo1.tpe} does not conform to upper bound ${hi1.tpe}", tree.pos) + if (false) // need to do in later phase, as this might cause a cyclic reference error. See pos/t0039.scala + if (!(lo1.tpe <:< hi1.tpe)) + ctx.error(i"lower bound ${lo1.tpe} does not conform to upper bound ${hi1.tpe}", tree.pos) assignType(cpy.TypeBoundsTree(tree, lo1, hi1), lo1, hi1) } diff --git a/tests/new/t0039.scala b/tests/new/t0039.scala new file mode 100644 index 000000000..652c606b0 --- /dev/null +++ b/tests/new/t0039.scala @@ -0,0 +1,6 @@ +abstract class Extensible[A, This <: Extensible[A, This]](x: A, xs: This) { self: This => + def mkObj(x: A, xs: This): This; +} +class Fixed[A](x: A, xs: Fixed[A]) extends Extensible[A, Fixed[A]](x, xs) { + def mkObj(x: A, xs: Fixed[A]) = new Fixed(x, xs); +} -- cgit v1.2.3