diff options
Diffstat (limited to 'src/compiler/scala/tools/nsc/typechecker/Typers.scala')
| -rw-r--r-- | src/compiler/scala/tools/nsc/typechecker/Typers.scala | 1366 |
1 files changed, 753 insertions, 613 deletions
diff --git a/src/compiler/scala/tools/nsc/typechecker/Typers.scala b/src/compiler/scala/tools/nsc/typechecker/Typers.scala index ac0a653626..69bf5fdef7 100644 --- a/src/compiler/scala/tools/nsc/typechecker/Typers.scala +++ b/src/compiler/scala/tools/nsc/typechecker/Typers.scala @@ -13,11 +13,12 @@ package scala package tools.nsc package typechecker -import scala.collection.{mutable, immutable} -import scala.reflect.internal.util.{ BatchSourceFile, Statistics, shortClassOfInstance, ListOfNil } +import scala.collection.{immutable, mutable} +import scala.reflect.internal.util.{ListOfNil, Statistics} import mutable.ListBuffer import symtab.Flags._ import Mode._ +import scala.reflect.macros.whitebox // Suggestion check whether we can do without priming scopes with symbols of outer scopes, // like the IDE does. @@ -105,12 +106,12 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper // that are turned private by typedBlock private final val SYNTHETIC_PRIVATE = TRANS_FLAG - private final val InterpolatorCodeRegex = """\$\{.*?\}""".r + private final val InterpolatorCodeRegex = """\$\{\s*(.*?)\s*\}""".r private final val InterpolatorIdentRegex = """\$[$\w]+""".r // note that \w doesn't include $ abstract class Typer(context0: Context) extends TyperDiagnostics with Adaptation with Tag with PatternTyper with TyperContextErrors { import context0.unit - import typeDebug.{ ptTree, ptBlock, ptLine, inGreen, inRed } + import typeDebug.ptTree import TyperErrorGen._ val runDefinitions = currentRun.runDefinitions import runDefinitions._ @@ -128,6 +129,22 @@ 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]) = { + val tp = appliedType(sym, args) + if (phase.erasedTypes) erasure.specialScalaErasure(tp) else tp + } + def typedDocDef(docDef: DocDef, mode: Mode, pt: Type): Tree = typed(docDef.definition, mode, pt) @@ -151,7 +168,9 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper for(ar <- argResultsBuff) paramTp = paramTp.subst(ar.subst.from, ar.subst.to) - val res = if (paramFailed || (paramTp.isErroneous && {paramFailed = true; true})) SearchFailure else inferImplicit(fun, paramTp, context.reportErrors, isView = false, context) + val res = + if (paramFailed || (paramTp.isErroneous && {paramFailed = true; true})) SearchFailure + else inferImplicitFor(paramTp, fun, context, reportAmbiguous = context.reportErrors) argResultsBuff += res if (res.isSuccess) { @@ -187,14 +206,12 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper !from.isError && !to.isError && context.implicitsEnabled - && (inferView(context.tree, from, to, reportAmbiguous = false, saveErrors = true) != EmptyTree) + && (inferView(context.tree, from, to, reportAmbiguous = false) != EmptyTree) // SI-8230 / SI-8463 We'd like to change this to `saveErrors = false`, but can't. // For now, we can at least pass in `context.tree` rather then `EmptyTree` so as // to avoid unpositioned type errors. ) - def inferView(tree: Tree, from: Type, to: Type, reportAmbiguous: Boolean): Tree = - inferView(tree, from, to, reportAmbiguous, saveErrors = true) /** Infer an implicit conversion (`view`) between two types. * @param tree The tree which needs to be converted. @@ -207,25 +224,23 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper * during the inference of a view be put into the original buffer. * False iff we don't care about them. */ - def inferView(tree: Tree, from: Type, to: Type, reportAmbiguous: Boolean, saveErrors: Boolean): Tree = { - debuglog("infer view from "+from+" to "+to)//debug - if (isPastTyper) EmptyTree - else from match { - case MethodType(_, _) => EmptyTree - case OverloadedType(_, _) => EmptyTree - case PolyType(_, _) => EmptyTree - case _ => - def wrapImplicit(from: Type): Tree = { - val result = inferImplicit(tree, functionType(from.withoutAnnotations :: Nil, to), reportAmbiguous, isView = true, context, saveAmbiguousDivergent = saveErrors) - if (result.subst != EmptyTreeTypeSubstituter) { - result.subst traverse tree - notifyUndetparamsInferred(result.subst.from, result.subst.to) - } - result.tree - } - wrapImplicit(from) orElse wrapImplicit(byNameType(from)) + def inferView(tree: Tree, from: Type, to: Type, reportAmbiguous: Boolean = true, saveErrors: Boolean = true): Tree = + if (isPastTyper || from.isInstanceOf[MethodType] || from.isInstanceOf[OverloadedType] || from.isInstanceOf[PolyType]) EmptyTree + else { + debuglog(s"Inferring view from $from to $to for $tree (reportAmbiguous= $reportAmbiguous, saveErrors=$saveErrors)") + + val fromNoAnnot = from.withoutAnnotations + val result = inferImplicitView(fromNoAnnot, to, tree, context, reportAmbiguous, saveErrors) match { + case fail if fail.isFailure => inferImplicitView(byNameType(fromNoAnnot), to, tree, context, reportAmbiguous, saveErrors) + case ok => ok + } + + if (result.subst != EmptyTreeTypeSubstituter) { + result.subst traverse tree + notifyUndetparamsInferred(result.subst.from, result.subst.to) + } + result.tree } - } import infer._ @@ -239,6 +254,10 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper var context = context0 def context1 = context + // for use with silent type checking to when we can't have results with undetermined type params + // note that this captures the context var + val isMonoContext = (_: Any) => context.undetparams.isEmpty + def dropExistential(tp: Type): Type = tp match { case ExistentialType(tparams, tpe) => new SubstWildcardMap(tparams).apply(tp) @@ -542,7 +561,11 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper } val qual = typedQualifier { atPos(tree.pos.makeTransparent) { tree match { - case Ident(_) => Ident(rootMirror.getPackageObjectWithMember(pre, sym)) + case Ident(_) => + val packageObject = + if (!sym.isOverloaded && sym.owner.isModuleClass) sym.owner.sourceModule // historical optimization, perhaps no longer needed + else pre.typeSymbol.packageObject + Ident(packageObject) case Select(qual, _) => Select(qual, nme.PACKAGEkw) case SelectFromTypeTree(qual, _) => Select(qual, nme.PACKAGEkw) } @@ -721,7 +744,7 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper featureTrait.owner.ownerChain.takeWhile(_ != languageFeatureModule.moduleClass).reverse val featureName = (nestedOwners map (_.name + ".")).mkString + featureTrait.name def action(): Boolean = { - def hasImport = inferImplicit(EmptyTree: Tree, featureTrait.tpe, reportAmbiguous = true, isView = false, context).isSuccess + def hasImport = inferImplicitByType(featureTrait.tpe, context).isSuccess def hasOption = settings.language contains featureName val OK = hasImport || hasOption if (!OK) { @@ -760,7 +783,7 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper else FunctionClass(numVparams) } - if (samSym.exists && samSym.owner != correspondingFunctionSymbol) // don't treat Functions as SAMs + if (samSym.exists && tp.typeSymbol != correspondingFunctionSymbol) // don't treat Functions as SAMs wildcardExtrapolation(normalize(tp memberInfo samSym)) else NoType } @@ -798,7 +821,8 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper * (11) Widen numeric literals to their expected type, if necessary * (12) When in mode EXPRmode, convert E to { E; () } if expected type is scala.Unit. * (13) When in mode EXPRmode, apply AnnotationChecker conversion if expected type is annotated. - * (14) When in mode EXPRmode, apply a view + * (14) When in mode EXPRmode, do SAM conversion + * (15) When in mode EXPRmode, apply a view * If all this fails, error */ protected def adapt(tree: Tree, mode: Mode, pt: Type, original: Tree = EmptyTree): Tree = { @@ -840,11 +864,24 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper case _ => } debuglog(s"fallback on implicits: ${tree}/$resetTree") - val tree1 = typed(resetTree, mode) - // Q: `typed` already calls `pluginsTyped` and `adapt`. the only difference here is that - // we pass `EmptyTree` as the `original`. intended? added in 2009 (53d98e7d42) by martin. - tree1 setType pluginsTyped(tree1.tpe, this, tree1, mode, pt) - if (tree1.isEmpty) tree1 else adapt(tree1, mode, pt, EmptyTree) + // SO-10066 Need to patch the enclosing tree in the context to make translation of Dynamic + // work during fallback typechecking below. + val resetContext: Context = { + object substResetForOriginal extends Transformer { + override def transform(tree: Tree): Tree = { + if (tree eq original) resetTree + else super.transform(tree) + } + } + context.make(substResetForOriginal.transform(context.tree)) + } + typerWithLocalContext(resetContext) { typer1 => + val tree1 = typer1.typed(resetTree, mode) + // Q: `typed` already calls `pluginsTyped` and `adapt`. the only difference here is that + // we pass `EmptyTree` as the `original`. intended? added in 2009 (53d98e7d42) by martin. + tree1 setType pluginsTyped(tree1.tpe, typer1, tree1, mode, pt) + if (tree1.isEmpty) tree1 else typer1.adapt(tree1, mode, pt, EmptyTree) + } } ) else @@ -858,9 +895,32 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper case Block(_, tree1) => tree1.symbol case _ => tree.symbol } - if (!meth.isConstructor && (isFunctionType(pt) || samOf(pt).exists)) { // (4.2) + + def cantAdapt = + if (context.implicitsEnabled) MissingArgsForMethodTpeError(tree, meth) + else setError(tree) + + // constructors do not eta-expand + if (meth.isConstructor) cantAdapt + // (4.2) eta-expand method value when function or sam type is expected + else if (isFunctionType(pt) || (!mt.params.isEmpty && samOf(pt).exists)) { + // SI-9536 `!mt.params.isEmpty &&`: for backwards compatibility with 2.11, + // we don't adapt a zero-arg method value to a SAM + // In 2.13, we won't do any eta-expansion for zero-arg method values, but we should deprecate first + debuglog(s"eta-expanding $tree: ${tree.tpe} to $pt") checkParamsConvertible(tree, tree.tpe) + + // SI-7187 eta-expansion of zero-arg method value is deprecated, switch order of (4.3) and (4.2) in 2.13 + def isExplicitEtaExpansion = original match { + case Typed(_, Function(Nil, EmptyTree)) => true // tree shape for `f _` + case _ => false + } + if (mt.params.isEmpty && !isExplicitEtaExpansion) { + currentRun.reporting.deprecationWarning(tree.pos, NoSymbol, + s"Eta-expansion of zero-argument method values is deprecated. Did you intend to write ${Apply(tree, Nil)}?", "2.12.0") + } + val tree0 = etaExpand(context.unit, tree, this) // #2624: need to infer type arguments for eta expansion of a polymorphic method @@ -874,12 +934,9 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper else typed(tree0, mode, pt) } - else if (!meth.isConstructor && mt.params.isEmpty) // (4.3) - adapt(typed(Apply(tree, Nil) setPos tree.pos), mode, pt, original) - else if (context.implicitsEnabled) - MissingArgsForMethodTpeError(tree, meth) - else - setError(tree) + // (4.3) apply to empty argument list -- TODO 2.13: move this one case up to avoid eta-expanding at arity 0 + else if (mt.params.isEmpty) adapt(typed(Apply(tree, Nil) setPos tree.pos), mode, pt, original) + else cantAdapt } def adaptType(): Tree = { @@ -928,24 +985,7 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper def insertApply(): Tree = { assert(!context.inTypeConstructorAllowed, mode) //@M val adapted = adaptToName(tree, nme.apply) - def stabilize0(pre: Type): Tree = stabilize(adapted, pre, MonoQualifierModes, WildcardType) - - // TODO reconcile the overlap between Typers#stablize and TreeGen.stabilize - val qual = adapted match { - case This(_) => - gen.stabilize(adapted) - case Ident(_) => - val owner = adapted.symbol.owner - val pre = - if (owner.isPackageClass) owner.thisType - else if (owner.isClass) context.enclosingSubClassContext(owner).prefix - else NoPrefix - stabilize0(pre) - case Select(qualqual, _) => - stabilize0(qualqual.tpe) - case other => - other - } + val qual = gen.stabilize(adapted) typedPos(tree.pos, mode, pt) { Select(qual setPos tree.pos.makeTransparent, nme.apply) } @@ -1020,72 +1060,75 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper } } - def fallbackAfterVanillaAdapt(): Tree = { - def isPopulatedPattern = { - if ((tree.symbol ne null) && tree.symbol.isModule) - inferModulePattern(tree, pt) - - isPopulated(tree.tpe, approximateAbstracts(pt)) + def adaptExprNotFunMode(): Tree = { + def lastTry(err: AbsTypeError = null): Tree = { + debuglog("error tree = " + tree) + if (settings.debug && settings.explaintypes) explainTypes(tree.tpe, pt) + if (err ne null) context.issue(err) + if (tree.tpe.isErroneous || pt.isErroneous) setError(tree) + else adaptMismatchedSkolems() } - if (mode.inPatternMode && isPopulatedPattern) - return tree - val tree1 = constfold(tree, pt) // (10) (11) - if (tree1.tpe <:< pt) - return adapt(tree1, mode, pt, original) + // TODO: should we even get to fallbackAfterVanillaAdapt for an ill-typed tree? + if (mode.typingExprNotFun && !tree.tpe.isErroneous) { + @inline def tpdPos(transformed: Tree) = typedPos(tree.pos, mode, pt)(transformed) + @inline def tpd(transformed: Tree) = typed(transformed, mode, pt) - if (mode.typingExprNotFun) { - // The <: Any requirement inhibits attempts to adapt continuation types - // to non-continuation types. - if (tree.tpe <:< AnyTpe) pt.dealias match { - case TypeRef(_, UnitClass, _) => // (12) - if (!isPastTyper && settings.warnValueDiscard) - context.warning(tree.pos, "discarded non-Unit value") - return typedPos(tree.pos, mode, pt)(Block(List(tree), Literal(Constant(())))) - case TypeRef(_, sym, _) if isNumericValueClass(sym) && isNumericSubType(tree.tpe, pt) => - if (!isPastTyper && settings.warnNumericWiden) - context.warning(tree.pos, "implicit numeric widening") - return typedPos(tree.pos, mode, pt)(Select(tree, "to" + sym.name)) - case _ => + @inline def warnValueDiscard(): Unit = if (!isPastTyper && settings.warnValueDiscard) { + def isThisTypeResult = (tree, tree.tpe) match { + case (Apply(Select(receiver, _), _), SingleType(_, sym)) => sym == receiver.symbol + case _ => false + } + if (!isThisTypeResult) context.warning(tree.pos, "discarded non-Unit value") } - if (pt.dealias.annotations.nonEmpty && canAdaptAnnotations(tree, this, mode, pt)) // (13) - return typed(adaptAnnotations(tree, this, mode, pt), mode, pt) - - if (hasUndets) - return instantiate(tree, mode, pt) - - if (context.implicitsEnabled && !pt.isError && !tree.isErrorTyped) { - // (14); the condition prevents chains of views - debuglog("inferring view from " + tree.tpe + " to " + pt) - inferView(tree, tree.tpe, pt, reportAmbiguous = true) match { - case EmptyTree => - case coercion => - def msg = "inferred view from " + tree.tpe + " to " + pt + " = " + coercion + ":" + coercion.tpe - if (settings.logImplicitConv) - context.echo(tree.pos, msg) - - debuglog(msg) - val silentContext = context.makeImplicit(context.ambiguousErrors) - val res = newTyper(silentContext).typed( - new ApplyImplicitView(coercion, List(tree)) setPos tree.pos, mode, pt) - silentContext.reporter.firstError match { - case Some(err) => context.issue(err) - case None => return res + @inline def warnNumericWiden(): Unit = + if (!isPastTyper && settings.warnNumericWiden) context.warning(tree.pos, "implicit numeric widening") + + // The <: Any requirement inhibits attempts to adapt continuation types to non-continuation types. + val anyTyped = tree.tpe <:< AnyTpe + + pt.dealias match { + case TypeRef(_, UnitClass, _) if anyTyped => // (12) + warnValueDiscard() ; tpdPos(gen.mkUnitBlock(tree)) + case TypeRef(_, numValueCls, _) if anyTyped && isNumericValueClass(numValueCls) && isNumericSubType(tree.tpe, pt) => // (10) (11) + warnNumericWiden() ; tpdPos(Select(tree, s"to${numValueCls.name}")) + case dealiased if dealiased.annotations.nonEmpty && canAdaptAnnotations(tree, this, mode, pt) => // (13) + tpd(adaptAnnotations(tree, this, mode, pt)) + case _ => + if (hasUndets) instantiate(tree, mode, pt) + else { + // (14) sam conversion + // TODO: figure out how to avoid partially duplicating typedFunction (samMatchingFunction) + // Could we infer the SAM type, assign it to the tree and add the attachment, + // all in one fell swoop at the end of typedFunction? + val samAttach = inferSamType(tree, pt, mode) + + if (samAttach.samTp ne NoType) tree.setType(samAttach.samTp).updateAttachment(samAttach) + else { // (15) implicit view application + val coercion = + if (context.implicitsEnabled) inferView(tree, tree.tpe, pt) + else EmptyTree + if (coercion ne EmptyTree) { + def msg = s"inferred view from ${tree.tpe} to $pt via $coercion: ${coercion.tpe}" + if (settings.logImplicitConv) context.echo(tree.pos, msg) + else debuglog(msg) + + val viewApplied = new ApplyImplicitView(coercion, List(tree)) setPos tree.pos + val silentContext = context.makeImplicit(context.ambiguousErrors) + val typedView = newTyper(silentContext).typed(viewApplied, mode, pt) + + silentContext.reporter.firstError match { + case None => typedView + case Some(err) => lastTry(err) + } + } else lastTry() } - } + } } - } - - debuglog("error tree = " + tree) - if (settings.debug && settings.explaintypes) - explainTypes(tree.tpe, pt) - - if (tree.tpe.isErroneous || pt.isErroneous) - setError(tree) - else - adaptMismatchedSkolems() + } else lastTry() } + def vanillaAdapt(tree: Tree) = { def applyPossible = { def applyMeth = member(adaptToName(tree, nme.apply), nme.apply) @@ -1119,8 +1162,13 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper } else if (tree.tpe <:< pt) tree - else - fallbackAfterVanillaAdapt() + else if (mode.inPatternMode && { inferModulePattern(tree, pt); isPopulated(tree.tpe, approximateAbstracts(pt)) }) + tree + else { + val constFolded = constfold(tree, pt) + if (constFolded.tpe <:< pt) adapt(constFolded, mode, pt, original) // set stage for (0) + else adaptExprNotFunMode() // (10) -- (15) + } } // begin adapt @@ -1139,7 +1187,7 @@ 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, @@ -1185,7 +1233,7 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper val savedUndetparams = context.undetparams silent(_.instantiate(tree, mode, UnitTpe)) orElse { _ => context.undetparams = savedUndetparams - val valueDiscard = atPos(tree.pos)(Block(List(instantiate(tree, mode, WildcardType)), Literal(Constant(())))) + val valueDiscard = atPos(tree.pos)(gen.mkUnitBlock(instantiate(tree, mode, WildcardType))) typed(valueDiscard, mode, UnitTpe) } } @@ -1246,7 +1294,7 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper * If no conversion is found, return `qual` unchanged. * */ - def adaptToArguments(qual: Tree, name: Name, args: List[Tree], pt: Type, reportAmbiguous: Boolean, saveErrors: Boolean): Tree = { + def adaptToArguments(qual: Tree, name: Name, args: List[Tree], pt: Type, reportAmbiguous: Boolean = true, saveErrors: Boolean = true): Tree = { def doAdapt(restpe: Type) = //util.trace("adaptToArgs "+qual+", name = "+name+", argtpes = "+(args map (_.tpe))+", pt = "+pt+" = ") adaptToMember(qual, HasMethodMatching(name, args map (_.tpe), restpe), reportAmbiguous, saveErrors) @@ -1262,7 +1310,7 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper * a method `name`. If that's ambiguous try taking arguments into * account using `adaptToArguments`. */ - def adaptToMemberWithArgs(tree: Tree, qual: Tree, name: Name, mode: Mode, reportAmbiguous: Boolean, saveErrors: Boolean): Tree = { + def adaptToMemberWithArgs(tree: Tree, qual: Tree, name: Name, mode: Mode, reportAmbiguous: Boolean = true, saveErrors: Boolean = true): Tree = { def onError(reportError: => Tree): Tree = context.tree match { case Apply(tree1, args) if (tree1 eq tree) && args.nonEmpty => ( silent (_.typedArgs(args.map(_.duplicate), mode)) @@ -1697,9 +1745,11 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper if (!isPastTyper && psym.hasDeprecatedInheritanceAnnotation && !sameSourceFile && !context.owner.ownerChain.exists(x => x.isDeprecated || x.hasBridgeAnnotation)) { - val suffix = psym.deprecatedInheritanceMessage map (": " + _) getOrElse "" - val msg = s"inheritance from ${psym.fullLocationString} is deprecated$suffix" - context.deprecationWarning(parent.pos, psym, msg) + val version = psym.deprecatedInheritanceVersion.getOrElse("") + val since = if (version.isEmpty) version else s" (since $version)" + val message = psym.deprecatedInheritanceMessage.map(msg => s": $msg").getOrElse("") + val report = s"inheritance from ${psym.fullLocationString} is deprecated$since$message" + context.deprecationWarning(parent.pos, psym, report, version) } val parentTypeOfThis = parent.tpe.dealias.typeOfThis @@ -1737,17 +1787,21 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper classinfo.parents map (_.instantiateTypeParams(List(tparam), List(AnyRefTpe))), classinfo.decls, clazz) - clazz.setInfo { - clazz.info match { - case PolyType(tparams, _) => PolyType(tparams, newinfo) - case _ => newinfo - } - } + updatePolyClassInfo(clazz, newinfo) FinitaryError(tparam) } } } + private def updatePolyClassInfo(clazz: Symbol, newinfo: ClassInfoType): clazz.type = { + clazz.setInfo { + clazz.info match { + case PolyType(tparams, _) => PolyType(tparams, newinfo) + case _ => newinfo + } + } + } + def typedClassDef(cdef: ClassDef): Tree = { val clazz = cdef.symbol val typedMods = typedModifiers(cdef.mods) @@ -1856,10 +1910,30 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper // please FIXME: uncommenting this line breaks everything // val templ = treeCopy.Template(templ0, templ0.body, templ0.self, templ0.parents) val clazz = context.owner + + val parentTypes = parents1.map(_.tpe) + + // The parents may have been normalized by typedParentTypes. + // We must update the info as well, or we won't find the super constructor for our now-first parent class + // Consider `class C ; trait T extends C ; trait U extends T` + // `U`'s info will start with parent `T`, but `typedParentTypes` will return `List(C, T)` (`== parents1`) + // now, the super call in the primary ctor will fail to find `C`'s ctor, since it bases its search on + // `U`'s info, not the trees. + // + // For correctness and performance, we restrict this rewrite to anonymous classes, + // as others have their parents in order already (it seems!), and we certainly + // don't want to accidentally rewire superclasses for e.g. the primitive value classes. + // + // TODO: Find an example of a named class needing this rewrite, I tried but couldn't find one. + if (clazz.isAnonymousClass && clazz.info.parents != parentTypes) { +// println(s"updating parents of $clazz from ${clazz.info.parents} to $parentTypes") + updatePolyClassInfo(clazz, ClassInfoType(parentTypes, clazz.info.decls, clazz)) + } + clazz.annotations.map(_.completeInfo()) if (templ.symbol == NoSymbol) templ setSymbol clazz.newLocalDummy(templ.pos) - val self1 = templ.self match { + val self1 = (templ.self: @unchecked) match { case vd @ ValDef(_, _, tpt, EmptyTree) => val tpt1 = checkNoEscaping.privates( clazz.thisSym, @@ -1897,11 +1971,8 @@ 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 @@ -1910,10 +1981,10 @@ 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) @@ -1956,13 +2027,20 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper // use typedValDef instead. this version is called after creating a new context for the ValDef private def typedValDefImpl(vdef: ValDef) = { val sym = vdef.symbol.initialize - val typedMods = typedModifiers(vdef.mods) + val typedMods = if (nme.isLocalName(sym.name) && sym.isPrivateThis && !vdef.mods.isPrivateLocal) { + // SI-10009 This tree has been given a field symbol by `enterGetterSetter`, patch up the + // modifiers accordingly so that we can survive resetAttrs and retypechecking. + // Similarly, we use `sym.name` rather than `vdef.name` below to use the local name. + typedModifiers(vdef.mods.copy(flags = sym.flags, privateWithin = tpnme.EMPTY)) + } else typedModifiers(vdef.mods) sym.annotations.map(_.completeInfo()) val tpt1 = checkNoEscaping.privates(sym, typedType(vdef.tpt)) checkNonCyclic(vdef, tpt1) - if (sym.hasAnnotation(definitions.VolatileAttr) && !sym.isMutable) + // allow trait accessors: it's the only vehicle we have to hang on to annotations that must be passed down to + // the field that's mixed into a subclass + if (sym.hasAnnotation(definitions.VolatileAttr) && !((sym hasFlag MUTABLE | LAZY) || (sym hasFlag ACCESSOR) && sym.owner.isTrait)) VolatileValueError(vdef) val rhs1 = @@ -1979,7 +2057,7 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper override def matches(sym: Symbol, sym1: Symbol) = if (sym.isSkolem) matches(sym.deSkolemize, sym1) else if (sym1.isSkolem) matches(sym, sym1.deSkolemize) - else super[SubstTypeMap].matches(sym, sym1) + else super.matches(sym, sym1) } // allow defaults on by-name parameters if (sym hasFlag BYNAMEPARAM) @@ -1989,7 +2067,7 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper } else tpt1.tpe transformedOrTyped(vdef.rhs, EXPRmode | BYVALmode, tpt2) } - treeCopy.ValDef(vdef, typedMods, vdef.name, tpt1, checkDead(rhs1)) setType NoType + treeCopy.ValDef(vdef, typedMods, sym.name, tpt1, checkDead(rhs1)) setType NoType } /** Enter all aliases of local parameter accessors. @@ -2028,35 +2106,39 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper case _ => (call, Nil) } - val (superConstr, superArgs) = decompose(rhs) - assert(superConstr.symbol ne null, superConstr)//debug - def superClazz = superConstr.symbol.owner - def superParamAccessors = superClazz.constrParamAccessors // associate superclass paramaccessors with their aliases - if (superConstr.symbol.isPrimaryConstructor && !superClazz.isJavaDefined && sameLength(superParamAccessors, superArgs)) { - for ((superAcc, superArg @ Ident(name)) <- superParamAccessors zip superArgs) { - if (mexists(vparamss)(_.symbol == superArg.symbol)) { - val alias = ( - superAcc.initialize.alias - orElse (superAcc getterIn superAcc.owner) - filter (alias => superClazz.info.nonPrivateMember(alias.name) == alias) - ) - if (alias.exists && !alias.accessed.isVariable && !isRepeatedParamType(alias.accessed.info)) { - val ownAcc = clazz.info decl name suchThat (_.isParamAccessor) match { - case acc if !acc.isDeferred && acc.hasAccessorFlag => acc.accessed - case acc => acc - } - ownAcc match { - case acc: TermSymbol if !acc.isVariable && !isByNameParamType(acc.info) => - debuglog(s"$acc has alias ${alias.fullLocationString}") - acc setAlias alias - case _ => + val (superConstr, superArgs) = decompose(rhs) + if (superConstr.symbol.isPrimaryConstructor) { + val superClazz = superConstr.symbol.owner + if (!superClazz.isJavaDefined) { + val superParamAccessors = superClazz.constrParamAccessors + if (sameLength(superParamAccessors, superArgs)) { + for ((superAcc, superArg@Ident(name)) <- superParamAccessors zip superArgs) { + if (mexists(vparamss)(_.symbol == superArg.symbol)) { + val alias = ( + superAcc.initialize.alias + orElse (superAcc getterIn superAcc.owner) + filter (alias => superClazz.info.nonPrivateMember(alias.name) == alias) + ) + if (alias.exists && !alias.accessed.isVariable && !isRepeatedParamType(alias.accessed.info)) { + val ownAcc = clazz.info decl name suchThat (_.isParamAccessor) match { + case acc if !acc.isDeferred && acc.hasAccessorFlag => acc.accessed + case acc => acc + } + ownAcc match { + case acc: TermSymbol if !acc.isVariable && !isByNameParamType(acc.info) => + debuglog(s"$acc has alias ${alias.fullLocationString}") + acc setAlias alias + case _ => + } + } } } } } } + pending.foreach(ErrorUtils.issueTypeError) } @@ -2158,6 +2240,8 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper } def typedDefDef(ddef: DefDef): DefDef = { + // an accessor's type completer may mutate a type inside `ddef` (`== context.unit.synthetics(ddef.symbol)`) + // concretely: it sets the setter's parameter type or the getter's return type (when derived from a valdef with empty tpt) val meth = ddef.symbol.initialize reenterTypeParams(ddef.tparams) @@ -2167,7 +2251,7 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper if (!isPastTyper && meth.isPrimaryConstructor) { for (vparams <- ddef.vparamss; vd <- vparams) { if (vd.mods.isParamAccessor) { - namer.validateParam(vd) + vd.symbol setAnnotations (vd.symbol.annotations filter AnnotationInfo.mkFilter(ParamTargetClass, defaultRetention = true)) } } } @@ -2203,9 +2287,10 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper transformedOrTyped(ddef.rhs, EXPRmode, tpt1.tpe) } - if (meth.isClassConstructor && !isPastTyper && !meth.owner.isSubClass(AnyValClass)) { - // At this point in AnyVal there is no supercall, which will blow up - // in computeParamAliases; there's nothing to be computed for Anyval anyway. + if (meth.isClassConstructor && !isPastTyper && !meth.owner.isSubClass(AnyValClass) && !meth.isJava) { + // There are no supercalls for AnyVal or constructors from Java sources, which + // would blow up in computeParamAliases; there's nothing to be computed for them + // anyway. if (meth.isPrimaryConstructor) computeParamAliases(meth.owner, vparamss1, rhs1) else @@ -2223,7 +2308,7 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper val allParams = meth.paramss.flatten for (p <- allParams) { for (n <- p.deprecatedParamName) { - if (allParams.exists(p1 => p1.name == n || (p != p1 && p1.deprecatedParamName.exists(_ == n)))) + if (allParams.exists(p1 => p != p1 && (p1.name == n || p1.deprecatedParamName.exists(_ == n)))) DeprecatedParamNameError(p, n) } } @@ -2319,7 +2404,7 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper for (stat <- block.stats) enterLabelDef(stat) if (phaseId(currentPeriod) <= currentRun.typerPhase.id) { - // This is very tricky stuff, because we are navigating the Skylla and Charybdis of + // This is very tricky stuff, because we are navigating the Scylla and Charybdis of // anonymous classes and what to return from them here. On the one hand, we cannot admit // every non-private member of an anonymous class as a part of the structural type of the // enclosing block. This runs afoul of the restriction that a structural type may not @@ -2351,31 +2436,49 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper } // The block is an anonymous class definitions/instantiation pair // -> members that are hidden by the type of the block are made private - val toHide = ( - classDecls filter (member => - member.isTerm - && member.isPossibleInRefinement - && member.isPublic - && !matchesVisibleMember(member) - ) map (member => member - resetFlag (PROTECTED | LOCAL) - setFlag (PRIVATE | SYNTHETIC_PRIVATE) - setPrivateWithin NoSymbol - ) - ) - syntheticPrivates ++= toHide + classDecls foreach { toHide => + if (toHide.isTerm + && toHide.isPossibleInRefinement + && toHide.isPublic + && !matchesVisibleMember(toHide)) { + (toHide + resetFlag (PROTECTED | LOCAL) + setFlag (PRIVATE | SYNTHETIC_PRIVATE) + setPrivateWithin NoSymbol) + + syntheticPrivates += toHide + } + } + case _ => } } - val stats1 = if (isPastTyper) block.stats else - block.stats.flatMap(stat => stat match { - case vd@ValDef(_, _, _, _) if vd.symbol.isLazy => - namer.addDerivedTrees(Typer.this, vd) - case _ => stat::Nil - }) - val stats2 = typedStats(stats1, context.owner) + val statsTyped = typedStats(block.stats, context.owner, warnPure = false) val expr1 = typed(block.expr, mode &~ (FUNmode | QUALmode), pt) - treeCopy.Block(block, stats2, expr1) + + // sanity check block for unintended expr placement + if (!isPastTyper) { + val (count, result0, adapted) = + expr1 match { + case Block(expr :: Nil, Literal(Constant(()))) => (1, expr, true) + case Literal(Constant(())) => (0, EmptyTree, false) + case _ => (1, EmptyTree, false) + } + def checkPure(t: Tree, supple: Boolean): Unit = + if (treeInfo.isPureExprForWarningPurposes(t)) { + val msg = "a pure expression does nothing in statement position" + 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) + } + statsTyped.foreach(checkPure(_, supple = false)) + if (result0.nonEmpty) checkPure(result0, supple = true) + } + + 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 @@ -2464,7 +2567,7 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper // TODO: add fallback __match sentinel to predef val matchStrategy: Tree = - if (!(settings.Xexperimental && context.isNameInScope(vpmName._match))) null // fast path, avoiding the next line if there's no __match to be seen + if (!(settings.Yvirtpatmat && context.isNameInScope(vpmName._match))) null // fast path, avoiding the next line if there's no __match to be seen else newTyper(context.makeImplicit(reportAmbiguousErrors = false)).silent(_.typed(Ident(vpmName._match)), reportAmbiguousErrors = false) orElse (_ => null) if (matchStrategy ne null) // virtualize @@ -2576,8 +2679,8 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper // the default uses applyOrElse's first parameter since the scrut's type has been widened val match_ = { - val defaultCase = methodBodyTyper.typedCase( - mkDefaultCase(methodBodyTyper.typed1(REF(default) APPLY (REF(x)), mode, B1.tpe).setType(B1.tpe)), argTp, B1.tpe) + val cdef = mkDefaultCase(methodBodyTyper.typed1(REF(default) APPLY (REF(x)), mode, B1.tpe).setType(B1.tpe)) + val List(defaultCase) = methodBodyTyper.typedCases(List(cdef), argTp, B1.tpe) treeCopy.Match(match0, match0.selector, match0.cases :+ defaultCase) } match_ setType B1.tpe @@ -2705,187 +2808,99 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper } } - /** Synthesize and type check the implementation of a type with a Single Abstract Method - * - * `{ (p1: T1, ..., pN: TN) => body } : S` - * - * expands to (where `S` is the expected type that defines a single abstract method named `apply`) - * - * `{ - * def apply$body(p1: T1, ..., pN: TN): T = body - * new S { - * def apply(p1: T1', ..., pN: TN'): T' = apply$body(p1,..., pN) - * } - * }` - * - * If 'T' is not fully defined, it is inferred by type checking - * `apply$body` without a result type before type checking the block. - * The method's inferred result type is used instead of `T`. [See test/files/pos/sammy_poly.scala] - * - * The `apply` method is identified by the argument `sam`; `S` corresponds to the argument `samClassTp`, - * and `resPt` is derived from `samClassTp` -- it may be fully defined, or not... - * If it is not fully defined, we derive `samClassTpFullyDefined` by inferring any unknown type parameters. - * - * The types T1' ... TN' and T' are derived from the method signature of the sam method, - * as seen from the fully defined `samClassTpFullyDefined`. - * - * The function's body is put in a method outside of the class definition to enforce scoping. - * S's members should not be in scope in `body`. - * - * The restriction on implicit arguments (neither S's constructor, nor sam may take an implicit argument list), - * is largely to keep the implementation of type inference (the computation of `samClassTpFullyDefined`) simple. - * - * NOTE: it would be nicer to not have to type check `apply$body` separately when `T` is not fully defined. - * However T must be fully defined before we type the instantiation, as it'll end up as a parent type, - * which must be fully defined. Would be nice to have some kind of mechanism to insert type vars in a block of code, - * and have the instantiation of the first occurrence propagate to the rest of the block. - * - * TODO: by-name params - * scala> trait LazySink { def accept(a: => Any): Unit } - * defined trait LazySink - * - * scala> val f: LazySink = (a) => (a, a) - * f: LazySink = $anonfun$1@1fb26910 - * - * scala> f(println("!")) - * <console>:10: error: LazySink does not take parameters - * f(println("!")) - * ^ - * - * scala> f.accept(println("!")) - * ! - * ! - */ - def synthesizeSAMFunction(sam: Symbol, fun: Function, resPt: Type, samClassTp: Type, mode: Mode): Tree = { - // assert(fun.vparams forall (vp => isFullyDefined(vp.tpt.tpe))) -- by construction, as we take them from sam's info - val sampos = fun.pos - - // if the expected sam type is fully defined, use it for the method's result type - // otherwise, NoType, so that type inference will determine the method's result type - // resPt is syntactically contained in samClassTp, so if the latter is fully defined, so is the former - // ultimately, we want to fully define samClassTp as it is used as the superclass of our anonymous class - val samDefTp = if (isFullyDefined(resPt)) resPt else NoType - val bodyName = newTermName(sam.name + "$body") - - // `def '${sam.name}\$body'($p1: $T1, ..., $pN: $TN): $resPt = $body` - val samBodyDef = - DefDef(NoMods, - bodyName, - Nil, - List(fun.vparams.map(_.duplicate)), // must duplicate as we're also using them for `samDef` - TypeTree(samDefTp) setPos sampos.focus, - fun.body) - - // If we need to enter the sym for the body def before type checking the block, - // we'll create a nested context, as explained below. - var nestedTyper = this - - // Type check body def before classdef to fully determine samClassTp (if necessary). - // As `samClassTp` determines a parent type for the class, - // we can't type check `block` in one go unless `samClassTp` is fully defined. - val samClassTpFullyDefined = - if (isFullyDefined(samClassTp)) samClassTp + /** Synthesize and type check the implementation of a type with a Single Abstract Method. + * + * Based on a type checked Function node `{ (p1: T1, ..., pN: TN) => body } : S` + * where `S` is the expected type that defines a single abstract method (call it `apply` for the example), + * that has signature `(p1: T1', ..., pN: TN'): T'`, synthesize the instantiation of the following anonymous class + * + * ``` + * new S { + * def apply$body(p1: T1, ..., pN: TN): T = body + * def apply(p1: T1', ..., pN: TN'): T' = apply$body(p1,..., pN) + * } + * ``` + * + * The `apply` method is identified by the argument `sam`; `S` corresponds to the argument `pt`, + * If `pt` is not fully defined, we derive `samClassTpFullyDefined` by inferring any unknown type parameters. + * + * The types T1' ... TN' and T' are derived from the method signature of the sam method, + * as seen from the fully defined `samClassTpFullyDefined`. + * + * The function's body is put in a (static) method in the class definition to enforce scoping. + * S's members should not be in scope in `body`. (Putting it in the block outside the class runs into implementation problems described below) + * + * The restriction on implicit arguments (neither S's constructor, nor sam may take an implicit argument list), + * is to keep the implementation of type inference (the computation of `samClassTpFullyDefined`) simple. + * + * Impl notes: + * - `fun` has a FunctionType, but the expected type `pt` is some SAM type -- let's remedy that + * - `fun` is fully attributed, so we'll have to wrangle some symbols into shape (owner change, vparam syms) + * - after experimentation, it works best to type check function literals fully first and then adapt to a sam type, + * as opposed to a sam-specific code paths earlier on in type checking (in typedFunction). + * For one, we want to emit the same bytecode regardless of whether the expected + * function type is a built-in FunctionN or some SAM type + * + */ + def inferSamType(fun: Tree, pt: Type, mode: Mode): SAMFunction = { + val sam = + if (fun.isInstanceOf[Function] && !isFunctionType(pt)) { + // TODO: can we ensure there's always a SAMFunction attachment, instead of looking up the sam again??? + // seems like overloading complicates things? + val sam = samOf(pt) + if (samMatchesFunctionBasedOnArity(sam, fun.asInstanceOf[Function].vparams)) sam + else NoSymbol + } else NoSymbol + + def fullyDefinedMeetsExpectedFunTp(pt: Type): Boolean = isFullyDefined(pt) && { + val samMethType = pt memberInfo sam + fun.tpe <:< functionType(samMethType.paramTypes, samMethType.resultType) + } + + SAMFunction( + if (!sam.exists) NoType + else if (fullyDefinedMeetsExpectedFunTp(pt)) pt else try { - // This creates a symbol for samBodyDef with a type completer that'll be triggered immediately below. - // The symbol is entered in the same scope used for the block below, and won't thus be reentered later. - // It has to be a new scope, though, or we'll "get ambiguous reference to overloaded definition" [pos/sammy_twice.scala] - // makeSilent: [pos/nonlocal-unchecked.scala -- when translation all functions to sams] - val nestedCtx = enterSym(context.makeNewScope(context.tree, context.owner).makeSilent(), samBodyDef) - nestedTyper = newTyper(nestedCtx) - - // NOTE: this `samBodyDef.symbol.info` runs the type completer set up by the enterSym above - val actualSamType = samBodyDef.symbol.info + val samClassSym = pt.typeSymbol // we're trying to fully define the type arguments for this type constructor - val samTyCon = samClassTp.typeSymbol.typeConstructor + val samTyCon = samClassSym.typeConstructor // the unknowns - val tparams = samClassTp.typeSymbol.typeParams + val tparams = samClassSym.typeParams // ... as typevars - val tvars = tparams map freshVar - - // 1. Recover partial information: - // - derive a type from samClassTp that has the corresponding tparams for type arguments that aren't fully defined - // - constrain typevars to be equal to type args that are fully defined - val samClassTpMoreDefined = appliedType(samTyCon, - (samClassTp.typeArgs, tparams, tvars).zipped map { - case (a, _, tv) if isFullyDefined(a) => tv =:= a; a - case (_, p, _) => p.typeConstructor - }) - - // the method type we're expecting the synthesized sam to have, based on the expected sam type, - // where fully defined type args to samClassTp have been preserved, - // with the unknown args replaced by their corresponding type param - val expectedSamType = samClassTpMoreDefined.memberInfo(sam) + val tvars = tparams map freshVar - // 2. make sure the body def's actual type (formals and result) conforms to - // sam's expected type (in terms of the typevars that represent the sam's class's type params) - actualSamType <:< expectedSamType.substituteTypes(tparams, tvars) + val ptVars = appliedType(samTyCon, tvars) - // solve constraints tracked by tvars - val targs = solvedTypes(tvars, tparams, tparams map varianceInType(sam.info), upper = false, lubDepth(sam.info :: Nil)) + // carry over info from pt + ptVars <:< pt - debuglog(s"sam infer: $samClassTp --> ${appliedType(samTyCon, targs)} by $actualSamType <:< $expectedSamType --> $targs for $tparams") + val samInfoWithTVars = ptVars.memberInfo(sam) - // a fully defined samClassTp - appliedType(samTyCon, targs) - } catch { - case _: NoInstance | _: TypeError => - devWarning(sampos, s"Could not define type $samClassTp using ${samBodyDef.symbol.rawInfo} <:< ${samClassTp memberInfo sam} (for $sam)") - samClassTp - } - - // what's the signature of the method that we should actually be overriding? - val samMethTp = samClassTpFullyDefined memberInfo sam - // Before the mutation, `tp <:< vpar.tpt.tpe` should hold. - // TODO: error message when this is not the case, as the expansion won't type check - // - Ti' <:< Ti and T <: T' must hold for the samDef body to type check - val funArgTps = foreach2(samMethTp.paramTypes, fun.vparams)((tp, vpar) => vpar.tpt setType tp) - - // `final override def ${sam.name}($p1: $T1', ..., $pN: $TN'): ${samMethTp.finalResultType} = ${sam.name}\$body'($p1, ..., $pN)` - val samDef = - DefDef(Modifiers(FINAL | OVERRIDE | SYNTHETIC), - sam.name.toTermName, - Nil, - List(fun.vparams), - TypeTree(samMethTp.finalResultType) setPos sampos.focus, - Apply(Ident(bodyName), fun.vparams map gen.paramToArg) - ) + // use function type subtyping, not method type subtyping (the latter is invariant in argument types) + fun.tpe <:< functionType(samInfoWithTVars.paramTypes, samInfoWithTVars.finalResultType) - val serializableParentAddendum = - if (typeIsSubTypeOfSerializable(samClassTp)) Nil - else List(TypeTree(SerializableTpe)) - - val classDef = - ClassDef(Modifiers(FINAL), tpnme.ANON_FUN_NAME, tparams = Nil, - gen.mkTemplate( - parents = TypeTree(samClassTpFullyDefined) :: serializableParentAddendum, - self = noSelfType, - constrMods = NoMods, - vparamss = ListOfNil, - body = List(samDef), - superPos = sampos.focus - ) - ) + val variances = tparams map varianceInType(sam.info) - // type checking the whole block, so that everything is packaged together nicely - // and we don't have to create any symbols by hand - val block = - nestedTyper.typedPos(sampos, mode, samClassTpFullyDefined) { - Block( - samBodyDef, - classDef, - Apply(Select(New(Ident(tpnme.ANON_FUN_NAME)), nme.CONSTRUCTOR), Nil) - ) - } + // solve constraints tracked by tvars + val targs = solvedTypes(tvars, tparams, variances, upper = false, lubDepth(sam.info :: Nil)) - // TODO: improve error reporting -- when we're in silent mode (from `silent(_.doTypedApply(tree, fun, args, mode, pt)) orElse onError`) - // the errors in the function don't get out... - if (block exists (_.isErroneous)) - context.error(fun.pos, s"Could not derive subclass of $samClassTp\n (with SAM `def $sam$samMethTp`)\n based on: $fun.") + debuglog(s"sam infer: $pt --> ${appliedType(samTyCon, targs)} by ${fun.tpe} <:< $samInfoWithTVars --> $targs for $tparams") - classDef.symbol addAnnotation SerialVersionUIDAnnotation - block + val ptFullyDefined = appliedType(samTyCon, targs) + if (ptFullyDefined <:< pt && fullyDefinedMeetsExpectedFunTp(ptFullyDefined)) { + debuglog(s"sam fully defined expected type: $ptFullyDefined from $pt for ${fun.tpe}") + ptFullyDefined + } else { + debuglog(s"Could not define type $pt using ${fun.tpe} <:< ${pt memberInfo sam} (for $sam)") + NoType + } + } catch { + case e@(_: NoInstance | _: TypeError) => + debuglog(s"Error during SAM synthesis: could not define type $pt using ${fun.tpe} <:< ${pt memberInfo sam} (for $sam)\n$e") + NoType + }, sam) } /** Type check a function literal. @@ -2895,16 +2910,19 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper * - a type with a Single Abstract Method (under -Xexperimental for now). */ private def typedFunction(fun: Function, mode: Mode, pt: Type): Tree = { - val numVparams = fun.vparams.length + val vparams = fun.vparams + val numVparams = vparams.length val FunctionSymbol = if (numVparams > definitions.MaxFunctionArity) NoSymbol else FunctionClass(numVparams) + val ptSym = pt.typeSymbol + /* The Single Abstract Member of pt, unless pt is the built-in function type of the expected arity, * as `(a => a): Int => Int` should not (yet) get the sam treatment. */ val sam = - if (pt.typeSymbol == FunctionSymbol) NoSymbol + if (ptSym == NoSymbol || ptSym == FunctionSymbol || ptSym == PartialFunctionClass) NoSymbol else samOf(pt) /* The SAM case comes first so that this works: @@ -2912,79 +2930,101 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper * (a => a): MyFun * * Note that the arity of the sam must correspond to the arity of the function. + * TODO: handle vararg sams? */ - val samViable = sam.exists && sameLength(sam.info.params, fun.vparams) - val ptNorm = if (samViable) samToFunctionType(pt, sam) else pt + val ptNorm = + if (samMatchesFunctionBasedOnArity(sam, vparams)) samToFunctionType(pt, sam) + else pt val (argpts, respt) = ptNorm baseType FunctionSymbol match { case TypeRef(_, FunctionSymbol, args :+ res) => (args, res) - case _ => (fun.vparams map (_ => if (pt == ErrorType) ErrorType else NoType), WildcardType) + case _ => (vparams map (if (pt == ErrorType) (_ => ErrorType) else (_ => NoType)), WildcardType) } - if (!FunctionSymbol.exists) - MaxFunctionArityError(fun) - else if (argpts.lengthCompare(numVparams) != 0) - WrongNumberOfParametersError(fun, argpts) + if (!FunctionSymbol.exists) MaxFunctionArityError(fun) + else if (argpts.lengthCompare(numVparams) != 0) WrongNumberOfParametersError(fun, argpts) else { - var issuedMissingParameterTypeError = false - foreach2(fun.vparams, argpts) { (vparam, argpt) => + val paramsMissingType = mutable.ArrayBuffer.empty[ValDef] //.sizeHint(numVparams) probably useless, since initial size is 16 and max fun arity is 22 + // first, try to define param types from expected function's arg types if needed + foreach2(vparams, argpts) { (vparam, argpt) => if (vparam.tpt.isEmpty) { - val vparamType = - if (isFullyDefined(argpt)) argpt - else { - fun match { - case etaExpansion(vparams, fn, args) => - silent(_.typed(fn, mode.forFunMode, pt)) filter (_ => context.undetparams.isEmpty) map { fn1 => - // if context.undetparams is not empty, the function was polymorphic, - // so we need the missing arguments to infer its type. See #871 - //println("typing eta "+fun+":"+fn1.tpe+"/"+context.undetparams) - val ftpe = normalize(fn1.tpe) baseType FunctionClass(numVparams) - if (isFunctionType(ftpe) && isFullyDefined(ftpe)) - return typedFunction(fun, mode, ftpe) - } - case _ => - } - MissingParameterTypeError(fun, vparam, pt, withTupleAddendum = !issuedMissingParameterTypeError) - issuedMissingParameterTypeError = true - ErrorType - } - vparam.tpt.setType(vparamType) + if (isFullyDefined(argpt)) vparam.tpt setType argpt + else paramsMissingType += vparam + if (!vparam.tpt.pos.isDefined) vparam.tpt setPos vparam.pos.focus } } - fun.body match { - // translate `x => x match { <cases> }` : PartialFunction to - // `new PartialFunction { def applyOrElse(x, default) = x match { <cases> } def isDefinedAt(x) = ... }` - case Match(sel, cases) if (sel ne EmptyTree) && (pt.typeSymbol == PartialFunctionClass) => - // go to outer context -- must discard the context that was created for the Function since we're discarding the function - // thus, its symbol, which serves as the current context.owner, is not the right owner - // you won't know you're using the wrong owner until lambda lift crashes (unless you know better than to use the wrong owner) - val outerTyper = newTyper(context.outer) - val p = fun.vparams.head - if (p.tpt.tpe == null) p.tpt setType outerTyper.typedType(p.tpt).tpe + // If we're typing `(a1: T1, ..., aN: TN) => m(a1,..., aN)`, where some Ti are not fully defined, + // type `m` directly (undoing eta-expansion of method m) to determine the argument types. + // This tree is the result from one of: + // - manual eta-expansion with named arguments (x => f(x)); + // - wildcard-style eta expansion (`m(_, _,)`); + // - instantiateToMethodType adapting a tree of method type to a function type using etaExpand. + // + // Note that method values are a separate thing (`m _`): they have the idiosyncratic shape + // of `Typed(expr, Function(Nil, EmptyTree))` + val ptUnrollingEtaExpansion = + if (paramsMissingType.nonEmpty && pt != ErrorType) fun.body match { + // we can compare arguments and parameters by name because there cannot be a binder between + // the function's valdefs and the Apply's arguments + case Apply(meth, args) if (vparams corresponds args) { case (p, Ident(name)) => p.name == name case _ => false } => + // We're looking for a method (as indicated by FUNmode in the silent typed below), + // so let's make sure our expected type is a MethodType + val methArgs = NoSymbol.newSyntheticValueParams(argpts map { case NoType => WildcardType case tp => tp }) + silent(_.typed(meth, mode.forFunMode, MethodType(methArgs, respt))) filter (isMonoContext) map { methTyped => + // if context.undetparams is not empty, the method was polymorphic, + // so we need the missing arguments to infer its type. See #871 + val funPt = normalize(methTyped.tpe) baseType FunctionClass(numVparams) + // println(s"typeUnEtaExpanded $meth : ${methTyped.tpe} --> normalized: $funPt") + + // If we are sure this function type provides all the necessary info, so that we won't have + // any undetermined argument types, go ahead an recurse below (`typedFunction(fun, mode, ptUnrollingEtaExpansion)`) + // and rest assured we won't end up right back here (and keep recursing) + if (isFunctionType(funPt) && funPt.typeArgs.iterator.take(numVparams).forall(isFullyDefined)) funPt + else null + } orElse { _ => null } + case _ => null + } else null + + + if (ptUnrollingEtaExpansion ne null) typedFunction(fun, mode, ptUnrollingEtaExpansion) + else { + // we ran out of things to try, missing parameter types are an irrevocable error + var issuedMissingParameterTypeError = false + paramsMissingType.foreach { vparam => + vparam.tpt setType ErrorType + MissingParameterTypeError(fun, vparam, pt, withTupleAddendum = !issuedMissingParameterTypeError) + issuedMissingParameterTypeError = true + } - outerTyper.synthesizePartialFunction(p.name, p.pos, paramSynthetic = false, fun.body, mode, pt) + fun.body match { + // translate `x => x match { <cases> }` : PartialFunction to + // `new PartialFunction { def applyOrElse(x, default) = x match { <cases> } def isDefinedAt(x) = ... }` + case Match(sel, cases) if (sel ne EmptyTree) && (pt.typeSymbol == PartialFunctionClass) => + // go to outer context -- must discard the context that was created for the Function since we're discarding the function + // thus, its symbol, which serves as the current context.owner, is not the right owner + // you won't know you're using the wrong owner until lambda lift crashes (unless you know better than to use the wrong owner) + val outerTyper = newTyper(context.outer) + val p = vparams.head + if (p.tpt.tpe == null) p.tpt setType outerTyper.typedType(p.tpt).tpe - // Use synthesizeSAMFunction to expand `(p1: T1, ..., pN: TN) => body` - // to an instance of the corresponding anonymous subclass of `pt`. - case _ if samViable => - newTyper(context.outer).synthesizeSAMFunction(sam, fun, respt, pt, mode) + outerTyper.synthesizePartialFunction(p.name, p.pos, paramSynthetic = false, fun.body, mode, pt) - // regular Function - case _ => - val vparamSyms = fun.vparams map { vparam => - enterSym(context, vparam) - if (context.retyping) context.scope enter vparam.symbol - vparam.symbol - } - val vparams = fun.vparams mapConserve typedValDef - val formals = vparamSyms map (_.tpe) - val body1 = typed(fun.body, respt) - val restpe = packedType(body1, fun.symbol).deconst.resultType - val funtpe = appliedType(FunctionSymbol, formals :+ restpe: _*) + case _ => + val vparamSyms = vparams map { vparam => + enterSym(context, vparam) + if (context.retyping) context.scope enter vparam.symbol + vparam.symbol + } + val vparamsTyped = vparams mapConserve typedValDef + val formals = vparamSyms map (_.tpe) + val body1 = typed(fun.body, respt) + val restpe = packedType(body1, fun.symbol).deconst.resultType + val funtpe = phasedAppliedType(FunctionSymbol, formals :+ restpe) - treeCopy.Function(fun, vparams, body1) setType funtpe + treeCopy.Function(fun, vparamsTyped, body1) setType funtpe + } } } } @@ -3012,99 +3052,124 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper case _ => log("unhandled import: "+imp+" in "+unit); imp } - def typedStats(stats: List[Tree], exprOwner: Symbol): List[Tree] = { + def typedStats(stats: List[Tree], exprOwner: Symbol, warnPure: Boolean = true): List[Tree] = { val inBlock = exprOwner == context.owner def includesTargetPos(tree: Tree) = tree.pos.isRange && context.unit.exists && (tree.pos includes context.unit.targetPos) val localTarget = stats exists includesTargetPos - def typedStat(stat: Tree): Tree = { - if (context.owner.isRefinementClass && !treeInfo.isDeclarationOrTypeDef(stat)) - OnlyDeclarationsError(stat) - else - stat match { - case imp @ Import(_, _) => - imp.symbol.initialize - if (!imp.symbol.isError) { - context = context.make(imp) - typedImport(imp) - } else EmptyTree - case _ => - if (localTarget && !includesTargetPos(stat)) { - // skip typechecking of statements in a sequence where some other statement includes - // the targetposition - stat - } else { - val localTyper = if (inBlock || (stat.isDef && !stat.isInstanceOf[LabelDef])) { - this - } else newTyper(context.make(stat, exprOwner)) - // XXX this creates a spurious dead code warning if an exception is thrown - // in a constructor, even if it is the only thing in the constructor. - val result = checkDead(localTyper.typedByValueExpr(stat)) - - if (treeInfo.isSelfOrSuperConstrCall(result)) { - context.inConstructorSuffix = true - if (treeInfo.isSelfConstrCall(result) && result.symbol.pos.pointOrElse(0) >= exprOwner.enclMethod.pos.pointOrElse(0)) - ConstructorsOrderError(stat) - } - - if (!isPastTyper && treeInfo.isPureExprForWarningPurposes(result)) context.warning(stat.pos, - "a pure expression does nothing in statement position; " + - "you may be omitting necessary parentheses" - ) - result - } + def typedStat(stat: Tree): Tree = stat match { + case s if context.owner.isRefinementClass && !treeInfo.isDeclarationOrTypeDef(s) => OnlyDeclarationsError(s) + case imp @ Import(_, _) => + imp.symbol.initialize + if (!imp.symbol.isError) { + context = context.make(imp) + typedImport(imp) + } else EmptyTree + // skip typechecking of statements in a sequence where some other statement includes the targetposition + case s if localTarget && !includesTargetPos(s) => s + case _ => + val localTyper = if (inBlock || (stat.isDef && !stat.isInstanceOf[LabelDef])) this + else newTyper(context.make(stat, exprOwner)) + // XXX this creates a spurious dead code warning if an exception is thrown + // in a constructor, even if it is the only thing in the constructor. + val result = checkDead(localTyper.typedByValueExpr(stat)) + + if (treeInfo.isSelfOrSuperConstrCall(result)) { + context.inConstructorSuffix = true + if (treeInfo.isSelfConstrCall(result)) { + if (result.symbol == exprOwner.enclMethod) + ConstructorRecursesError(stat) + else if (result.symbol.pos.pointOrElse(0) >= exprOwner.enclMethod.pos.pointOrElse(0)) + ConstructorsOrderError(stat) + } + } + if (warnPure && !isPastTyper && treeInfo.isPureExprForWarningPurposes(result)) { + val msg = "a pure expression does nothing in statement position" + val clause = if (stats.lengthCompare(1) > 0) "; multiline expressions may require enclosing parentheses" else "" + context.warning(stat.pos, s"${msg}${clause}") } + result } - /* 'accessor' and 'accessed' are so similar it becomes very difficult to - * follow the logic, so I renamed one to something distinct. - */ + // TODO: adapt to new trait field encoding, figure out why this exemption is made + // 'accessor' and 'accessed' are so similar it becomes very difficult to + //follow the logic, so I renamed one to something distinct. def accesses(looker: Symbol, accessed: Symbol) = accessed.isLocalToThis && ( - (accessed.isParamAccessor) - || (looker.hasAccessorFlag && !accessed.hasAccessorFlag && accessed.isPrivate) - ) + (accessed.isParamAccessor) + || (looker.hasAccessorFlag && !accessed.hasAccessorFlag && accessed.isPrivate) + ) - def checkNoDoubleDefs: Unit = { - val scope = if (inBlock) context.scope else context.owner.info.decls + def checkNoDoubleDefs(scope: Scope): Unit = { var e = scope.elems while ((e ne null) && e.owner == scope) { var e1 = scope.lookupNextEntry(e) while ((e1 ne null) && e1.owner == scope) { - if (!accesses(e.sym, e1.sym) && !accesses(e1.sym, e.sym) && - (e.sym.isType || inBlock || (e.sym.tpe matches e1.sym.tpe))) - // default getters are defined twice when multiple overloads have defaults. an - // error for this is issued in RefChecks.checkDefaultsInOverloaded - if (!e.sym.isErroneous && !e1.sym.isErroneous && !e.sym.hasDefault && - !e.sym.hasAnnotation(BridgeClass) && !e1.sym.hasAnnotation(BridgeClass)) { - log("Double definition detected:\n " + - ((e.sym.getClass, e.sym.info, e.sym.ownerChain)) + "\n " + - ((e1.sym.getClass, e1.sym.info, e1.sym.ownerChain))) - - DefDefinedTwiceError(e.sym, e1.sym) - scope.unlink(e1) // need to unlink to avoid later problems with lub; see #2779 - } - e1 = scope.lookupNextEntry(e1) + val sym = e.sym + val sym1 = e1.sym + + /** From the spec (refchecks checks other conditions regarding erasing to the same type and default arguments): + * + * A block expression [... its] statement sequence may not contain two definitions or + * declarations that bind the same name --> `inBlock` + * + * It is an error if a template directly defines two matching members. + * + * A member definition $M$ _matches_ a member definition $M'$, if $M$ and $M'$ bind the same name, + * and one of following holds: + * 1. Neither $M$ nor $M'$ is a method definition. + * 2. $M$ and $M'$ define both monomorphic methods with equivalent argument types. + * 3. $M$ defines a parameterless method and $M'$ defines a method with an empty parameter list `()` or _vice versa_. + * 4. $M$ and $M'$ define both polymorphic methods with equal number of argument types $\overline T$, $\overline T'$ + * and equal numbers of type parameters $\overline t$, $\overline t'$, say, + * and $\overline T' = [\overline t'/\overline t]\overline T$. + */ + if (!(accesses(sym, sym1) || accesses(sym1, sym)) // TODO: does this purely defer errors until later? + && (inBlock || !(sym.isMethod || sym1.isMethod) || (sym.tpe matches sym1.tpe)) + // default getters are defined twice when multiple overloads have defaults. + // The error for this is deferred until RefChecks.checkDefaultsInOverloaded + && (!sym.isErroneous && !sym1.isErroneous && !sym.hasDefault && + !sym.hasAnnotation(BridgeClass) && !sym1.hasAnnotation(BridgeClass))) { + log("Double definition detected:\n " + + ((sym.getClass, sym.info, sym.ownerChain)) + "\n " + + ((sym1.getClass, sym1.info, sym1.ownerChain))) + + DefDefinedTwiceError(sym, sym1) + scope.unlink(e1) // need to unlink to avoid later problems with lub; see #2779 + } + e1 = scope.lookupNextEntry(e1) } e = e.next } } - def addSynthetics(stats: List[Tree]): List[Tree] = { - val scope = if (inBlock) context.scope else context.owner.info.decls + def addSynthetics(stats: List[Tree], scope: Scope): List[Tree] = { var newStats = new ListBuffer[Tree] var moreToAdd = true - val retractErroneousSynthetics = settings.isScala212 - while (moreToAdd) { val initElems = scope.elems // SI-5877 The decls of a package include decls of the package object. But we don't want to add // the corresponding synthetics to the package class, only to the package object class. - def shouldAdd(sym: Symbol) = - inBlock || !context.isInPackageObject(sym, context.owner) + // SI-6734 Locality test below is meaningless if we're not even in the correct tree. + // For modules that are synthetic case companions, check that case class is defined here. + def shouldAdd(sym: Symbol): Boolean = { + def shouldAddAsModule: Boolean = + sym.moduleClass.attachments.get[ClassForCaseCompanionAttachment] match { + case Some(att) => + val cdef = att.caseClass + stats.exists { + case t @ ClassDef(_, _, _, _) => t.symbol == cdef.symbol // cdef ne t + case _ => false + } + case _ => true + } + + (!sym.isModule || shouldAddAsModule) && (inBlock || !context.isInPackageObject(sym, context.owner)) + } for (sym <- scope) - for (tree <- context.unit.synthetics get sym if shouldAdd(sym)) { // OPT: shouldAdd is usually true. Call it here, rather than in the outer loop + // OPT: shouldAdd is usually true. Call it here, rather than in the outer loop + for (tree <- context.unit.synthetics.get(sym) if shouldAdd(sym)) { // if the completer set the IS_ERROR flag, retract the stat (currently only used by applyUnapplyMethodCompleter) - if (!(retractErroneousSynthetics && sym.initialize.hasFlag(IS_ERROR))) + if (!sym.initialize.hasFlag(IS_ERROR)) newStats += typedStat(tree) // might add even more synthetics to the scope context.unit.synthetics -= sym } @@ -3132,6 +3197,10 @@ 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 } @@ -3150,11 +3219,14 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper val stats1 = stats mapConserve typedStat if (phase.erasedTypes) stats1 else { + val scope = if (inBlock) context.scope else context.owner.info.decls + // As packages are open, it doesn't make sense to check double definitions here. Furthermore, - // it is expensive if the package is large. Instead, such double defininitions are checked in `Namers.enterInScope` + // it is expensive if the package is large. Instead, such double definitions are checked in `Namers.enterInScope` if (!context.owner.isPackageClass) - checkNoDoubleDefs - addSynthetics(stats1) + checkNoDoubleDefs(scope) + + addSynthetics(stats1, scope) } } @@ -3218,6 +3290,9 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper // less expensive than including them in inferMethodAlternative (see below). def shapeType(arg: Tree): Type = arg match { case Function(vparams, body) => + // No need for phasedAppliedType, as we don't get here during erasure -- + // overloading resolution happens during type checking. + // During erasure, the condition above (fun.symbol.isOverloaded) is false. functionType(vparams map (_ => AnyTpe), shapeType(body)) case AssignOrNamedArg(Ident(name), rhs) => NamedType(name, shapeType(rhs)) @@ -3254,40 +3329,74 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper } val fun = preSelectOverloaded(fun0) + val argslen = args.length fun.tpe match { case OverloadedType(pre, alts) => def handleOverloaded = { val undetparams = context.undetparams + + def funArgTypes(tpAlts: List[(Type, Symbol)]) = tpAlts.map { case (tp, alt) => + val relTp = tp.asSeenFrom(pre, alt.owner) + val argTps = functionOrSamArgTypes(relTp) + //println(s"funArgTypes $argTps from $relTp") + argTps.map(approximateAbstracts) + } + + def functionProto(argTpWithAlt: List[(Type, Symbol)]): Type = + try functionType(funArgTypes(argTpWithAlt).transpose.map(lub), WildcardType) + catch { case _: IllegalArgumentException => WildcardType } + + // To propagate as much information as possible to typedFunction, which uses the expected type to + // infer missing parameter types for Function trees that we're typing as arguments here, + // we expand the parameter types for all alternatives to the expected argument length, + // then transpose to get a list of alternative argument types (push down the overloading to the arguments). + // Thus, for each `arg` in `args`, the corresponding `argPts` in `altArgPts` is a list of expected types + // for `arg`. Depending on which overload is picked, only one of those expected types must be met, but + // we're in the process of figuring that out, so we'll approximate below by normalizing them to function types + // and lubbing the argument types (we treat SAM and FunctionN types equally, but non-function arguments + // do not receive special treatment: they are typed under WildcardType.) + val altArgPts = + if (settings.isScala212 && args.exists(treeInfo.isFunctionMissingParamType)) + try alts.map(alt => formalTypes(alt.info.paramTypes, argslen).map(ft => (ft, alt))).transpose // do least amount of work up front + catch { case _: IllegalArgumentException => args.map(_ => Nil) } // fail safe in case formalTypes fails to align to argslen + else args.map(_ => Nil) // will type under argPt == WildcardType + val (args1, argTpes) = context.savingUndeterminedTypeParams() { val amode = forArgMode(fun, mode) - def typedArg0(tree: Tree) = typedArg(tree, amode, BYVALmode, WildcardType) - args.map { - case arg @ AssignOrNamedArg(Ident(name), rhs) => - // named args: only type the righthand sides ("unknown identifier" errors otherwise) - // the assign is untyped; that's ok because we call doTypedApply - val typedRhs = typedArg0(rhs) - val argWithTypedRhs = treeCopy.AssignOrNamedArg(arg, arg.lhs, typedRhs) - - // TODO: SI-8197/SI-4592: check whether this named argument could be interpreted as an assign + + map2(args, altArgPts) { (arg, argPtAlts) => + def typedArg0(tree: Tree) = { + // if we have an overloaded HOF such as `(f: Int => Int)Int <and> (f: Char => Char)Char`, + // and we're typing a function like `x => x` for the argument, try to collapse + // the overloaded type into a single function type from which `typedFunction` + // can derive the argument type for `x` in the function literal above + val argPt = + if (argPtAlts.nonEmpty && treeInfo.isFunctionMissingParamType(tree)) functionProto(argPtAlts) + else WildcardType + + val argTyped = typedArg(tree, amode, BYVALmode, argPt) + (argTyped, argTyped.tpe.deconst) + } + + arg match { + // SI-8197/SI-4592 call for checking whether this named argument could be interpreted as an assign // infer.checkNames must not use UnitType: it may not be a valid assignment, or the setter may return another type from Unit - // - // var typedAsAssign = true - // val argTyped = silent(_.typedArg(argWithTypedRhs, amode, BYVALmode, WildcardType)) orElse { errors => - // typedAsAssign = false - // argWithTypedRhs - // } - // - // TODO: add an assignmentType field to NamedType, equal to: - // assignmentType = if (typedAsAssign) argTyped.tpe else NoType - - (argWithTypedRhs, NamedType(name, typedRhs.tpe.deconst)) - case arg @ treeInfo.WildcardStarArg(repeated) => - val arg1 = typedArg0(arg) - (arg1, RepeatedType(arg1.tpe.deconst)) - case arg => - val arg1 = typedArg0(arg) - (arg1, arg1.tpe.deconst) + // TODO: just make it an error to refer to a non-existent named arg, as it's far more likely to be + // a typo than an assignment passed as an argument + case AssignOrNamedArg(lhs@Ident(name), rhs) => + // named args: only type the righthand sides ("unknown identifier" errors otherwise) + // the assign is untyped; that's ok because we call doTypedApply + typedArg0(rhs) match { + case (rhsTyped, tp) => (treeCopy.AssignOrNamedArg(arg, lhs, rhsTyped), NamedType(name, tp)) + } + case treeInfo.WildcardStarArg(_) => + typedArg0(arg) match { + case (argTyped, tp) => (argTyped, RepeatedType(tp)) + } + case _ => + typedArg0(arg) + } }.unzip } if (context.reporter.hasErrors) @@ -3308,7 +3417,7 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper // governed by a) the argument types and b) the expected type val args1 = typedArgs(args, forArgMode(fun, mode)) val pts = args1.map(_.tpe.deconst) - val clone = fun.symbol.cloneSymbol + val clone = fun.symbol.cloneSymbol.withoutAnnotations val cloneParams = pts map (pt => clone.newValueParameter(currentUnit.freshTermName()).setInfo(pt)) val resultType = if (isFullyDefined(pt)) pt else ObjectTpe clone.modifyInfo(mt => copyMethodType(mt, cloneParams, resultType)) @@ -3318,32 +3427,31 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper case mt @ MethodType(params, _) => val paramTypes = mt.paramTypes // repeat vararg as often as needed, remove by-name - val argslen = args.length val formals = formalTypes(paramTypes, argslen) - /* Try packing all arguments into a Tuple and apply `fun` - * to that. This is the last thing which is tried (after - * default arguments) + /* Try packing all arguments into a Tuple and apply `fun` to that. + * This is the last thing which is tried (after default arguments). */ - def tryTupleApply: Tree = { - if (eligibleForTupleConversion(paramTypes, argslen) && !phase.erasedTypes) { + def tryTupleApply: Tree = + if (phase.erasedTypes || !eligibleForTupleConversion(paramTypes, argslen)) EmptyTree + else { val tupleArgs = List(atPos(tree.pos.makeTransparent)(gen.mkTuple(args))) // expected one argument, but got 0 or >1 ==> try applying to tuple // the inner "doTypedApply" does "extractUndetparams" => restore when it fails val savedUndetparams = context.undetparams - silent(_.doTypedApply(tree, fun, tupleArgs, mode, pt)) map { t => - // Depending on user options, may warn or error here if - // a Unit or tuple was inserted. - val keepTree = ( - !mode.typingExprNotFun // why? introduced in 4e488a60, doc welcome - || t.symbol == null // ditto - || checkValidAdaptation(t, args) - ) - if (keepTree) t else EmptyTree - } orElse { _ => context.undetparams = savedUndetparams ; EmptyTree } + // May warn or error if a Unit or tuple was inserted. + def validate(t: Tree): Tree = { + // regardless of typer's mode + val invalidAdaptation = t.symbol != null && !checkValidAdaptation(t, args) + // only bail if we're typing an expression (and not inside another application) + if (invalidAdaptation && mode.typingExprNotFun) EmptyTree else t + } + def reset(errors: Seq[AbsTypeError]): Tree = { + context.undetparams = savedUndetparams + EmptyTree + } + silent(_.doTypedApply(tree, fun, tupleArgs, mode, pt)).map(validate).orElse(reset) } - else EmptyTree - } /* Treats an application which uses named or default arguments. * Also works if names + a vararg used: when names are used, the vararg @@ -3363,7 +3471,10 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper // #2064 duplErrorTree(WrongNumberOfArgsError(tree, fun)) } else if (lencmp > 0) { - tryTupleApply orElse duplErrorTree(TooManyArgsNamesDefaultsError(tree, fun)) + tryTupleApply orElse duplErrorTree { + val (namelessArgs, argPos) = removeNames(Typer.this)(args, params) + TooManyArgsNamesDefaultsError(tree, fun, formals, args, namelessArgs, argPos) + } } else if (lencmp == 0) { // we don't need defaults. names were used, so this application is transformed // into a block (@see transformNamedApplication in NamesDefaults) @@ -3427,7 +3538,7 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper val lencmp2 = compareLengths(allArgs, formals) if (!sameLength(allArgs, args) && callToCompanionConstr(context, funSym)) { - duplErrorTree(ModuleUsingCompanionClassDefaultArgsErrror(tree)) + duplErrorTree(ModuleUsingCompanionClassDefaultArgsError(tree)) } else if (lencmp2 > 0) { removeNames(Typer.this)(allArgs, params) // #3818 duplErrTree @@ -3663,7 +3774,7 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper val annType = annTpt.tpe finish( - if (typedFun.isErroneous) + if (typedFun.isErroneous || annType == null) ErroneousAnnotation else if (annType.typeSymbol isNonBottomSubClass ClassfileAnnotationClass) { // annotation to be saved as java classfile annotation @@ -3672,10 +3783,12 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper reportAnnotationError(MultipleArgumentListForAnnotationError(ann)) } else { - val annScope = annType.decls - .filter(sym => sym.isMethod && !sym.isConstructor && sym.isJavaDefined) + val annScopeJava = + if (isJava) annType.decls.filter(sym => sym.isMethod && !sym.isConstructor && sym.isJavaDefined) + else EmptyScope // annScopeJava is only used if isJava + val names = mutable.Set[Symbol]() - names ++= (if (isJava) annScope.iterator + names ++= (if (isJava) annScopeJava.iterator else typedFun.tpe.params.iterator) def hasValue = names exists (_.name == nme.value) @@ -3686,7 +3799,7 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper val nvPairs = args map { case arg @ AssignOrNamedArg(Ident(name), rhs) => - val sym = if (isJava) annScope.lookup(name) + val sym = if (isJava) annScopeJava.lookup(name) else findSymbol(typedFun.tpe.params)(_.name == name) if (sym == NoSymbol) { reportAnnotationError(UnknownAnnotationNameError(arg, name)) @@ -3742,7 +3855,7 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper } if (annType.typeSymbol == DeprecatedAttr && argss.flatten.size < 2) - context.deprecationWarning(ann.pos, DeprecatedAttr, "@deprecated now takes two arguments; see the scaladoc.") + context.deprecationWarning(ann.pos, DeprecatedAttr, "@deprecated now takes two arguments; see the scaladoc.", "2.11.0") if ((typedAnn.tpe == null) || typedAnn.tpe.isErroneous) ErroneousAnnotation else annInfo(typedAnn) @@ -4140,6 +4253,14 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper ann setType arg1.tpe.withAnnotation(annotInfo) } val atype = ann.tpe + // For `f(): @inline/noinline` callsites, add the InlineAnnotatedAttachment. TypeApplys + // are eliminated by erasure, so add it to the underlying function in this case. + def setInlineAttachment(t: Tree, att: InlineAnnotatedAttachment): Unit = t match { + case TypeApply(fun, _) => setInlineAttachment(fun, att) + case _ => t.updateAttachment(att) + } + if (atype.hasAnnotation(definitions.ScalaNoInlineClass)) setInlineAttachment(arg1, NoInlineCallsiteAttachment) + else if (atype.hasAnnotation(definitions.ScalaInlineClass)) setInlineAttachment(arg1, InlineCallsiteAttachment) Typed(arg1, resultingTypeTree(atype)) setPos tree.pos setType atype } } @@ -4148,7 +4269,8 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper val name = tree.name val body = tree.body name match { - case name: TypeName => assert(body == EmptyTree, context.unit + " typedBind: " + name.debugString + " " + body + " " + body.getClass) + case name: TypeName => + assert(body == EmptyTree, s"${context.unit} typedBind: ${name.debugString} ${body} ${body.getClass}") val sym = if (tree.symbol != NoSymbol) tree.symbol else { @@ -4231,7 +4353,7 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper // if (varsym.isVariable || // // setter-rewrite has been done above, so rule out methods here, but, wait a minute, why are we assigning to non-variables after erasure?! // (phase.erasedTypes && varsym.isValue && !varsym.isMethod)) { - if (varsym.isVariable || varsym.isValue && phase.erasedTypes) { + if (varsym.isVariable || varsym.isValue && phase.assignsFields) { val rhs1 = typedByValueExpr(rhs, lhs1.tpe) treeCopy.Assign(tree, lhs1, checkDead(rhs1)) setType UnitTpe } @@ -4291,7 +4413,8 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper if (pt.typeSymbol == PartialFunctionClass) synthesizePartialFunction(newTermName(context.unit.fresh.newName("x")), tree.pos, paramSynthetic = true, tree, mode, pt) else { - val arity = if (isFunctionType(pt)) pt.dealiasWiden.typeArgs.length - 1 else 1 + val arity = functionArityFromType(pt) match { case -1 => 1 case arity => arity } // SI-8429: consider sam and function type equally in determining function arity + val params = for (i <- List.range(0, arity)) yield atPos(tree.pos.focusStart) { ValDef(Modifiers(PARAM | SYNTHETIC), @@ -4366,8 +4489,9 @@ 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 @@ -4391,31 +4515,43 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper treeCopy.New(tree, tpt1).setType(tp) } - def functionTypeWildcard(tree: Tree, arity: Int): Type = { - val tp = functionType(List.fill(arity)(WildcardType), WildcardType) - if (tp == NoType) MaxFunctionArityError(tree) - tp - } - - def typedEta(expr1: Tree): Tree = expr1.tpe match { - case TypeRef(_, ByNameParamClass, _) => - val expr2 = Function(List(), expr1) setPos expr1.pos - new ChangeOwnerTraverser(context.owner, expr2.symbol).traverse(expr2) - typed1(expr2, mode, pt) - case NullaryMethodType(restpe) => - val expr2 = Function(List(), expr1) setPos expr1.pos - new ChangeOwnerTraverser(context.owner, expr2.symbol).traverse(expr2) - typed1(expr2, mode, pt) - case PolyType(_, MethodType(formals, _)) => - if (isFunctionType(pt)) expr1 - else adapt(expr1, mode, functionTypeWildcard(expr1, formals.length)) - case MethodType(formals, _) => - if (isFunctionType(pt)) expr1 - else adapt(expr1, mode, functionTypeWildcard(expr1, formals.length)) + def functionTypeWildcard(arity: Int): Type = + functionType(List.fill(arity)(WildcardType), WildcardType) + + def checkArity(tree: Tree)(tp: Type): tp.type = tp match { + case NoType => MaxFunctionArityError(tree); tp + case _ => tp + } + + + /** Eta expand an expression like `m _`, where `m` denotes a method or a by-name argument + * + * The spec says: + * The expression `$e$ _` is well-formed if $e$ is of method type or if $e$ is a call-by-name parameter. + * (1) If $e$ is a method with parameters, `$e$ _` represents $e$ converted to a function type + * by [eta expansion](#eta-expansion). + * (2) If $e$ is a parameterless method or call-by-name parameter of type `=>$T$`, `$e$ _` represents + * the function of type `() => $T$`, which evaluates $e$ when it is applied to the empty parameterlist `()`. + */ + def typedEta(methodValue: Tree, original: Tree): Tree = methodValue.tpe match { + case tp@(MethodType(_, _) | PolyType(_, MethodType(_, _))) => // (1) + val formals = tp.params + if (isFunctionType(pt) || samMatchesFunctionBasedOnArity(samOf(pt), formals)) methodValue + else adapt(methodValue, mode, checkArity(methodValue)(functionTypeWildcard(formals.length)), original) + + case TypeRef(_, ByNameParamClass, _) | NullaryMethodType(_) => // (2) + val pos = methodValue.pos + // must create it here to change owner (normally done by typed's typedFunction) + val funSym = context.owner.newAnonymousFunctionValue(pos) + new ChangeOwnerTraverser(context.owner, funSym) traverse methodValue + + typed(Function(List(), methodValue) setSymbol funSym setPos pos, mode, pt) + case ErrorType => - expr1 + methodValue + case _ => - UnderscoreEtaError(expr1) + UnderscoreEtaError(methodValue) } def tryTypedArgs(args: List[Tree], mode: Mode): Option[List[Tree]] = { @@ -4459,7 +4595,7 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper case Annotated(_, r) => treesInResult(r) case If(_, t, e) => treesInResult(t) ++ treesInResult(e) case Try(b, catches, _) => treesInResult(b) ++ catches - case Typed(r, Function(Nil, EmptyTree)) => treesInResult(r) + case Typed(r, Function(Nil, EmptyTree)) => treesInResult(r) // a method value case Select(qual, name) => treesInResult(qual) case Apply(fun, args) => treesInResult(fun) ++ args.flatMap(treesInResult) case TypeApply(fun, args) => treesInResult(fun) ++ args.flatMap(treesInResult) @@ -4478,7 +4614,7 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper tryTypedArgs(args, forArgMode(fun, mode)) match { case Some(args1) if !args1.exists(arg => arg.exists(_.isErroneous)) => val qual1 = - if (!pt.isError) adaptToArguments(qual, name, args1, pt, reportAmbiguous = true, saveErrors = true) + if (!pt.isError) adaptToArguments(qual, name, args1, pt) else qual if (qual1 ne qual) { val tree1 = Apply(Select(qual1, name) setPos fun.pos, args1) setPos tree.pos @@ -4534,19 +4670,20 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper val qual1 = typedQualifier(qual) if (treeInfo.isVariableOrGetter(qual1)) { if (Statistics.canEnable) Statistics.stopTimer(failedOpEqNanos, opeqStart) - val erred = qual1.isErroneous || args.exists(_.isErroneous) + val erred = qual1.exists(_.isErroneous) || args.exists(_.isErroneous) if (erred) reportError(error) else { val convo = convertToAssignment(fun, qual1, name, args) silent(op = _.typed1(convo, mode, pt)) match { case SilentResultValue(t) => t - case err: SilentTypeError => reportError(SilentTypeError(advice1(convo, error.errors, err), error.warnings)) + case err: SilentTypeError => reportError( + SilentTypeError(advice1(convo, error.errors, err), error.warnings) + ) } } - } - else { + } else { if (Statistics.canEnable) Statistics.stopTimer(failedApplyNanos, appStart) val Apply(Select(qual2, _), args2) = tree - val erred = qual2.isErroneous || args2.exists(_.isErroneous) + val erred = qual2.exists(_.isErroneous) || args2.exists(_.isErroneous) reportError { if (erred) error else SilentTypeError(advice2(error.errors), error.warnings) } @@ -4667,10 +4804,10 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper def findMixinSuper(site: Type): Type = { var ps = site.parents filter (_.typeSymbol.name == mix) if (ps.isEmpty) - ps = site.parents filter (_.typeSymbol.toInterface.name == mix) + ps = site.parents filter (_.typeSymbol.name == mix) if (ps.isEmpty) { debuglog("Fatal: couldn't find site " + site + " in " + site.parents.map(_.typeSymbol.name)) - if (phase.erasedTypes && context.enclClass.owner.isImplClass) { + if (phase.erasedTypes && context.enclClass.owner.isTrait) { // the reference to super class got lost during erasure restrictionError(tree.pos, unit, "traits may not select fields or methods from super[C] where C is a class") ErrorType @@ -4702,6 +4839,16 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper if (isStableContext(tree, mode, pt)) tree setType clazz.thisType else tree } + + // For Java, instance and static members are in the same scope, but we put the static ones in the companion object + // so, when we can't find a member in the class scope, check the companion + def inCompanionForJavaStatic(pre: Type, cls: Symbol, name: Name): Symbol = + if (!(context.unit.isJava && cls.isClass && !cls.isModuleClass)) NoSymbol else { + val companion = companionSymbolOf(cls, context) + if (!companion.exists) NoSymbol + else member(gen.mkAttributedRef(pre, companion), name) // assert(res.isStatic, s"inCompanionForJavaStatic($pre, $cls, $name) = $res ${res.debugFlagString}") + } + /* Attribute a selection where `tree` is `qual.name`. * `qual` is already attributed. */ @@ -4728,12 +4875,12 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper dyna.wrapErrors(t, (_.typed1(t, mode, pt))) } - val sym = tree.symbol orElse member(qual, name) orElse { + val sym = tree.symbol orElse member(qual, name) orElse inCompanionForJavaStatic(qual.tpe.prefix, qual.symbol, name) orElse { // symbol not found? --> try to convert implicitly to a type that does have the required // member. Added `| PATTERNmode` to allow enrichment in patterns (so we can add e.g., an // xml member to StringContext, which in turn has an unapply[Seq] method) if (name != nme.CONSTRUCTOR && mode.inAny(EXPRmode | PATTERNmode)) { - val qual1 = adaptToMemberWithArgs(tree, qual, name, mode, reportAmbiguous = true, saveErrors = true) + val qual1 = adaptToMemberWithArgs(tree, qual, name, mode) if ((qual1 ne qual) && !qual1.isErrorTyped) return typed(treeCopy.Select(tree, qual1, name), mode, pt) } @@ -4820,16 +4967,6 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper } } - // temporarily use `filter` as an alternative for `withFilter` - def tryWithFilterAndFilter(tree: Select, qual: Tree): Tree = { - def warn(sym: Symbol) = context.deprecationWarning(tree.pos, sym, s"`withFilter' method does not yet exist on ${qual.tpe.widen}, using `filter' method instead") - silent(_ => typedSelect(tree, qual, nme.withFilter)) orElse { _ => - silent(_ => typed1(Select(qual, nme.filter) setPos tree.pos, mode, pt)) match { - case SilentResultValue(res) => warn(res.symbol) ; res - case SilentTypeError(err) => WithFilterError(tree, err) - } - } - } def typedSelectOrSuperCall(tree: Select) = tree match { case Select(qual @ Super(_, _), nme.CONSTRUCTOR) => // the qualifier type of a supercall constructor is its first parent class @@ -4843,10 +4980,7 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper else UnstableTreeError(qualTyped) ) - val tree1 = name match { - case nme.withFilter if !settings.future => tryWithFilterAndFilter(tree, qualStableOrError) - case _ => typedSelect(tree, qualStableOrError, name) - } + val tree1 = typedSelect(tree, qualStableOrError, name) def sym = tree1.symbol if (tree.isInstanceOf[PostfixSelect]) checkFeature(tree.pos, PostfixOpsFeature, name.decode) @@ -5127,11 +5261,11 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper // because `expr` might contain nested macro calls (see SI-6673) // // Note: apparently `Function(Nil, EmptyTree)` is the secret parser marker - // which means trailing underscore. + // which means trailing underscore -- denoting a method value. See makeMethodValue in TreeBuilder. case Typed(expr, Function(Nil, EmptyTree)) => typed1(suppressMacroExpansion(expr), mode, pt) match { case macroDef if treeInfo.isMacroApplication(macroDef) => MacroEtaError(macroDef) - case exprTyped => typedEta(checkDead(exprTyped)) + case methodValue => typedEta(checkDead(methodValue), tree) } case Typed(expr, tpt) => val tpt1 = typedType(tpt, mode) // type the ascribed type first @@ -5222,17 +5356,23 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper case MethodType(p :: _, _) => p.isImplicit // implicit method requires no args case _ => true // catches all others including NullaryMethodType } - def isPlausible(m: Symbol) = m.alternatives exists (m => requiresNoArgs(m.info)) + def isPlausible(m: Symbol) = !m.isPackage && m.alternatives.exists(x => requiresNoArgs(x.info)) def maybeWarn(s: String): Unit = { def warn(message: String) = context.warning(lit.pos, s"possible missing interpolator: $message") def suspiciousSym(name: TermName) = context.lookupSymbol(name, _ => true).symbol - def suspiciousExpr = InterpolatorCodeRegex findFirstIn s + val suspiciousExprs = InterpolatorCodeRegex findAllMatchIn s def suspiciousIdents = InterpolatorIdentRegex findAllIn s map (s => suspiciousSym(TermName(s drop 1))) - - if (suspiciousExpr.nonEmpty) - warn("detected an interpolated expression") // "${...}" - else + def isCheapIdent(expr: String) = (Character.isJavaIdentifierStart(expr.charAt(0)) && + expr.tail.forall(Character.isJavaIdentifierPart)) + def warnableExpr(expr: String) = !expr.isEmpty && (!isCheapIdent(expr) || isPlausible(suspiciousSym(TermName(expr)))) + + if (suspiciousExprs.nonEmpty) { + val exprs = (suspiciousExprs map (_ group 1)).toList + // short-circuit on leading ${} + if (!exprs.head.isEmpty && exprs.exists(warnableExpr)) + warn("detected an interpolated expression") // "${...}" + } else suspiciousIdents find isPlausible foreach (sym => warn(s"detected interpolated identifier `$$${sym.name}`")) // "$id" } lit match { @@ -5256,7 +5396,7 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper if (refTyped.isErrorTyped) { setError(tree) } else { - tree setType refTyped.tpe.resultType + tree setType refTyped.tpe.resultType.deconst if (refTyped.isErrorTyped || treeInfo.admitsTypeSelection(refTyped)) tree else UnstableTreeError(tree) } @@ -5444,6 +5584,9 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper if (!isPastTyper) signalDone(context.asInstanceOf[analyzer.Context], tree, result) + if (mode.inPatternMode && !mode.inPolyMode && result.isType) + PatternMustBeValue(result, pt) + result } @@ -5535,10 +5678,7 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper // as a compromise, context.enrichmentEnabled tells adaptToMember to go ahead and enrich, // but arbitrary conversions (in adapt) are disabled // TODO: can we achieve the pattern matching bit of the string interpolation SIP without this? - typingInPattern(context.withImplicitsDisabledAllowEnrichment(typed(tree, PATTERNmode, pt))) match { - case tpt if tpt.isType => PatternMustBeValue(tpt, pt); tpt - case pat => pat - } + typingInPattern(context.withImplicitsDisabledAllowEnrichment(typed(tree, PATTERNmode, pt))) } /** Types a (fully parameterized) type tree */ @@ -5613,7 +5753,7 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper } def reportWarning(inferredType: Type) = { val explanation = s"inference of $inferredType from macro impl's c.Expr[$inferredType] is deprecated and is going to stop working in 2.12" - context.deprecationWarning(ddef.pos, ddef.symbol, s"$commonMessage ($explanation)") + context.deprecationWarning(ddef.pos, ddef.symbol, s"$commonMessage ($explanation)", "2.12.0") } computeMacroDefTypeFromMacroImplRef(ddef, rhs1) match { case ErrorType => ErrorType |