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author | Paul Phillips <paulp@improving.org> | 2013-03-13 11:13:09 -0700 |
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committer | Paul Phillips <paulp@improving.org> | 2013-03-13 11:13:09 -0700 |
commit | 79d653a183bf74e27ec77cfd591e9649f154d41b (patch) | |
tree | 0eccdac7e0a326b22742469425d2a309755a23b1 /src/compiler | |
parent | 184e0cc126c9499ea7572621663b14c37dba4734 (diff) | |
parent | 6ef63e49f8d762ac02367225ee737ea93f52a738 (diff) | |
download | scala-79d653a183bf74e27ec77cfd591e9649f154d41b.tar.gz scala-79d653a183bf74e27ec77cfd591e9649f154d41b.tar.bz2 scala-79d653a183bf74e27ec77cfd591e9649f154d41b.zip |
Merge pull request #2215 from paulp/issue/7228
SI-7228, bug in subtyping.
Diffstat (limited to 'src/compiler')
-rw-r--r-- | src/compiler/scala/tools/nsc/typechecker/Implicits.scala | 24 | ||||
-rw-r--r-- | src/compiler/scala/tools/nsc/typechecker/Namers.scala | 30 | ||||
-rw-r--r-- | src/compiler/scala/tools/nsc/typechecker/Typers.scala | 9 |
3 files changed, 30 insertions, 33 deletions
diff --git a/src/compiler/scala/tools/nsc/typechecker/Implicits.scala b/src/compiler/scala/tools/nsc/typechecker/Implicits.scala index 2331f82a58..5b11adf127 100644 --- a/src/compiler/scala/tools/nsc/typechecker/Implicits.scala +++ b/src/compiler/scala/tools/nsc/typechecker/Implicits.scala @@ -268,7 +268,7 @@ trait Implicits { */ object Function1 { val Sym = FunctionClass(1) - def unapply(tp: Type) = tp match { + def unapply(tp: Type) = tp baseType Sym match { case TypeRef(_, Sym, arg1 :: arg2 :: _) => Some((arg1, arg2)) case _ => None } @@ -431,10 +431,8 @@ trait Implicits { val start = if (Statistics.canEnable) Statistics.startTimer(matchesPtNanos) else null val result = normSubType(tp, pt) || isView && { pt match { - case TypeRef(_, Function1.Sym, arg1 :: arg2 :: Nil) => - matchesPtView(tp, arg1, arg2, undet) - case _ => - false + case Function1(arg1, arg2) => matchesPtView(tp, arg1, arg2, undet) + case _ => false } } if (Statistics.canEnable) Statistics.stopTimer(matchesPtNanos, start) @@ -575,21 +573,21 @@ trait Implicits { ) def fail(reason: String): SearchResult = failure(itree, reason) + def fallback = typed1(itree, EXPRmode, wildPt) try { - val itree1 = - if (isView) { - val arg1 :: arg2 :: _ = pt.typeArgs + val itree1 = if (!isView) fallback else pt match { + case Function1(arg1, arg2) => typed1( atPos(itree.pos)(Apply(itree, List(Ident("<argument>") setType approximate(arg1)))), EXPRmode, approximate(arg2) ) - } - else - typed1(itree, EXPRmode, wildPt) - - if (context.hasErrors) + case _ => fallback + } + if (context.hasErrors) { + log("implicit adapt failed: " + context.errBuffer.head.errMsg) return fail(context.errBuffer.head.errMsg) + } if (Statistics.canEnable) Statistics.incCounter(typedImplicits) diff --git a/src/compiler/scala/tools/nsc/typechecker/Namers.scala b/src/compiler/scala/tools/nsc/typechecker/Namers.scala index 007c7c6a83..d5da4967be 100644 --- a/src/compiler/scala/tools/nsc/typechecker/Namers.scala +++ b/src/compiler/scala/tools/nsc/typechecker/Namers.scala @@ -805,23 +805,19 @@ trait Namers extends MethodSynthesis { case _ => false } - - val tpe1 = dropIllegalStarTypes(tpe.deconst) - val tpe2 = tpe1.widen - - // This infers Foo.type instead of "object Foo" - // See Infer#adjustTypeArgs for the polymorphic case. - if (tpe.typeSymbolDirect.isModuleClass) tpe1 - else if (sym.isVariable || sym.isMethod && !sym.hasAccessorFlag) - if (tpe2 <:< pt) tpe2 else tpe1 - else if (isHidden(tpe)) tpe2 - // In an attempt to make pattern matches involving method local vals - // compilable into switches, for a time I had a more generous condition: - // `if (sym.isFinal || sym.isLocal) tpe else tpe1` - // This led to issues with expressions like classOf[List[_]] which apparently - // depend on being deconst-ed here, so this is again the original: - else if (!sym.isFinal) tpe1 - else tpe + val shouldWiden = ( + !tpe.typeSymbolDirect.isModuleClass // Infer Foo.type instead of "object Foo" + && (tpe.widen <:< pt) // Don't widen our way out of conforming to pt + && ( sym.isVariable + || sym.isMethod && !sym.hasAccessorFlag + || isHidden(tpe) + ) + ) + dropIllegalStarTypes( + if (shouldWiden) tpe.widen + else if (sym.isFinal) tpe // "final val" allowed to retain constant type + else tpe.deconst + ) } /** Computes the type of the body in a ValDef or DefDef, and * assigns the type to the tpt's node. Returns the type. diff --git a/src/compiler/scala/tools/nsc/typechecker/Typers.scala b/src/compiler/scala/tools/nsc/typechecker/Typers.scala index 92f53f4956..ba34ae4871 100644 --- a/src/compiler/scala/tools/nsc/typechecker/Typers.scala +++ b/src/compiler/scala/tools/nsc/typechecker/Typers.scala @@ -1124,16 +1124,19 @@ trait Typers extends Adaptations with Tags { else { if (mode.inExprModeButNot(FUNmode)) { pt.dealias match { - case TypeRef(_, sym, _) => + // The <: Any requirement inhibits attempts to adapt continuation types + // to non-continuation types. + case TypeRef(_, sym, _) if tree.tpe <:< AnyClass.tpe => // note: was if (pt.typeSymbol == UnitClass) but this leads to a potentially // infinite expansion if pt is constant type () - if (sym == UnitClass && tree.tpe <:< AnyClass.tpe) { // (12) + if (sym == UnitClass) { // (12) if (settings.warnValueDiscard.value) context.unit.warning(tree.pos, "discarded non-Unit value") return typedPos(tree.pos, mode, pt) { Block(List(tree), Literal(Constant())) } - } else if (isNumericValueClass(sym) && isNumericSubType(tree.tpe, pt)) { + } + else if (isNumericValueClass(sym) && isNumericSubType(tree.tpe, pt)) { if (settings.warnNumericWiden.value) context.unit.warning(tree.pos, "implicit numeric widening") return typedPos(tree.pos, mode, pt) { |