diff options
Diffstat (limited to 'src/compiler/scala/tools/nsc/typechecker/Typers.scala')
| -rw-r--r-- | src/compiler/scala/tools/nsc/typechecker/Typers.scala | 51 |
1 files changed, 25 insertions, 26 deletions
diff --git a/src/compiler/scala/tools/nsc/typechecker/Typers.scala b/src/compiler/scala/tools/nsc/typechecker/Typers.scala index a95ecd360c..3360599c1b 100644 --- a/src/compiler/scala/tools/nsc/typechecker/Typers.scala +++ b/src/compiler/scala/tools/nsc/typechecker/Typers.scala @@ -128,6 +128,15 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper def canTranslateEmptyListToNil = true def missingSelectErrorTree(tree: Tree, qual: Tree, name: Name): Tree = tree + // used to exempt synthetic accessors (i.e. those that are synthesized by the compiler to access a field) + // from skolemization because there's a weird bug that causes spurious type mismatches + // (it seems to have something to do with existential abstraction over values + // https://github.com/scala/scala-dev/issues/165 + // when we're past typer, lazy accessors are synthetic, but before they are user-defined + // to make this hack less hacky, we could rework our flag assignment to allow for + // requiring both the ACCESSOR and the SYNTHETIC bits to trigger the exemption + private def isSyntheticAccessor(sym: Symbol) = sym.isAccessor && (!sym.isLazy || isPastTyper) + // when type checking during erasure, generate erased types in spots that aren't transformed by erasure // (it erases in TypeTrees, but not in, e.g., the type a Function node) def phasedAppliedType(sym: Symbol, args: List[Type]) = { @@ -1159,7 +1168,7 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper adapt(tree setType restpe, mode, pt, original) case TypeRef(_, ByNameParamClass, arg :: Nil) if mode.inExprMode => // (2) adapt(tree setType arg, mode, pt, original) - case tp if mode.typingExprNotLhs && isExistentialType(tp) => + case tp if mode.typingExprNotLhs && isExistentialType(tp) && !isSyntheticAccessor(context.owner) => adapt(tree setType tp.dealias.skolemizeExistential(context.owner, tree), mode, pt, original) case PolyType(tparams, restpe) if mode.inNone(TAPPmode | PATTERNmode) && !context.inTypeConstructorAllowed => // (3) // assert((mode & HKmode) == 0) //@M a PolyType in HKmode represents an anonymous type function, @@ -1373,13 +1382,7 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper notAllowed(s"redefinition of $name method. See SIP-15, criterion 4.") else if (stat.symbol != null && stat.symbol.isParamAccessor) notAllowed("additional parameter") - // concrete accessor (getter) in trait corresponds to a field definition (neg/anytrait.scala) - // TODO: only reject accessors that actually give rise to field (e.g., a constant-type val is fine) - else if (!isValueClass && stat.symbol.isAccessor && !stat.symbol.isDeferred) - notAllowed("field definition") checkEphemeralDeep.traverse(rhs) - // for value class or "exotic" vals in traits - // (traits don't receive ValDefs for regular vals until fields phase -- well, except for early initialized/lazy vals) case _: ValDef => notAllowed("field definition") case _: ModuleDef => @@ -1956,11 +1959,8 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper if (!phase.erasedTypes && !clazz.info.resultType.isError) // @S: prevent crash for duplicated type members checkFinitary(clazz.info.resultType.asInstanceOf[ClassInfoType]) - val body2 = { - val body2 = - if (isPastTyper || reporter.hasErrors) body1 - else body1 flatMap rewrappingWrapperTrees(namer.addDerivedTrees(Typer.this, _)) - val primaryCtor = treeInfo.firstConstructor(body2) + val bodyWithPrimaryCtor = { + val primaryCtor = treeInfo.firstConstructor(body1) val primaryCtor1 = primaryCtor match { case DefDef(_, _, _, _, _, Block(earlyVals :+ global.pendingSuperCall, unit)) => val argss = superArgs(parents1.head) getOrElse Nil @@ -1969,10 +1969,10 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper deriveDefDef(primaryCtor)(block => Block(earlyVals :+ superCall, unit) setPos pos) setPos pos case _ => primaryCtor } - body2 mapConserve { case `primaryCtor` => primaryCtor1; case stat => stat } + body1 mapConserve { case `primaryCtor` => primaryCtor1; case stat => stat } } - val body3 = typedStats(body2, templ.symbol) + val body3 = typedStats(bodyWithPrimaryCtor, templ.symbol) if (clazz.info.firstParent.typeSymbol == AnyValClass) validateDerivedValueClass(clazz, body3) @@ -2436,13 +2436,7 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper case _ => } } - val stats1 = if (isPastTyper) block.stats else - block.stats.flatMap { - case vd@ValDef(_, _, _, _) if vd.symbol.isLazy => - namer.addDerivedTrees(Typer.this, vd) - case stat => stat::Nil - } - val stats2 = typedStats(stats1, context.owner, warnPure = false) + val statsTyped = typedStats(block.stats, context.owner, warnPure = false) val expr1 = typed(block.expr, mode &~ (FUNmode | QUALmode), pt) // sanity check block for unintended expr placement @@ -2456,18 +2450,18 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper def checkPure(t: Tree, supple: Boolean): Unit = if (treeInfo.isPureExprForWarningPurposes(t)) { val msg = "a pure expression does nothing in statement position" - val parens = if (stats2.length + count > 1) "multiline expressions might require enclosing parentheses" else "" + val parens = if (statsTyped.length + count > 1) "multiline expressions might require enclosing parentheses" else "" val discard = if (adapted) "; a value can be silently discarded when Unit is expected" else "" val text = if (supple) s"${parens}${discard}" else if (!parens.isEmpty) s"${msg}; ${parens}" else msg context.warning(t.pos, text) } - stats2.foreach(checkPure(_, supple = false)) + statsTyped.foreach(checkPure(_, supple = false)) if (result0.nonEmpty) checkPure(result0, supple = true) } - treeCopy.Block(block, stats2, expr1) + treeCopy.Block(block, statsTyped, expr1) .setType(if (treeInfo.isExprSafeToInline(block)) expr1.tpe else expr1.tpe.deconst) } finally { // enable escaping privates checking from the outside and recycle @@ -3171,6 +3165,10 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper case (ClassDef(cmods, cname, _, _), DefDef(dmods, dname, _, _, _, _)) => cmods.isImplicit && dmods.isImplicit && cname.toTermName == dname + // ValDef and Accessor + case (ValDef(_, cname, _, _), DefDef(_, dname, _, _, _, _)) => + cname.getterName == dname.getterName + case _ => false } @@ -4455,8 +4453,9 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper def narrowRhs(tp: Type) = { val sym = context.tree.symbol context.tree match { case ValDef(mods, _, _, Apply(Select(`tree`, _), _)) if !mods.isMutable && sym != null && sym != NoSymbol => - val sym1 = if (sym.owner.isClass && sym.getterIn(sym.owner) != NoSymbol) sym.getterIn(sym.owner) - else sym.lazyAccessorOrSelf + val sym1 = + if (sym.owner.isClass && sym.getterIn(sym.owner) != NoSymbol) sym.getterIn(sym.owner) + else sym val pre = if (sym1.owner.isClass) sym1.owner.thisType else NoPrefix intersectionType(List(tp, singleType(pre, sym1))) case _ => tp |