diff options
30 files changed, 825 insertions, 355 deletions
diff --git a/src/compiler/scala/tools/nsc/transform/UnCurry.scala b/src/compiler/scala/tools/nsc/transform/UnCurry.scala index 844774e75f..ef50ae276f 100644 --- a/src/compiler/scala/tools/nsc/transform/UnCurry.scala +++ b/src/compiler/scala/tools/nsc/transform/UnCurry.scala @@ -457,12 +457,11 @@ abstract class UnCurry extends InfoTransform else super.transform(tree) case UnApply(fn, args) => - val fn1 = transform(fn) - val args1 = transformTrees(fn.symbol.name match { - case nme.unapply => args - case nme.unapplySeq => transformArgs(tree.pos, fn.symbol, args, localTyper.expectedPatternTypes(fn, args)) - case _ => sys.error("internal error: UnApply node has wrong symbol") - }) + val fn1 = transform(fn) + val args1 = fn.symbol.name match { + case nme.unapplySeq => transformArgs(tree.pos, fn.symbol, args, patmat.alignPatterns(tree).expectedTypes) + case _ => args + } treeCopy.UnApply(tree, fn1, args1) case Apply(fn, args) => diff --git a/src/compiler/scala/tools/nsc/transform/patmat/MatchTranslation.scala b/src/compiler/scala/tools/nsc/transform/patmat/MatchTranslation.scala index 63f4a4bf25..699e98f963 100644 --- a/src/compiler/scala/tools/nsc/transform/patmat/MatchTranslation.scala +++ b/src/compiler/scala/tools/nsc/transform/patmat/MatchTranslation.scala @@ -31,6 +31,30 @@ trait MatchTranslation { trait MatchTranslator extends TreeMakers with TreeMakerWarnings { import typer.context + /** A conservative approximation of which patterns do not discern anything. + * They are discarded during the translation. + */ + object WildcardPattern { + def unapply(pat: Tree): Boolean = pat match { + case Bind(nme.WILDCARD, WildcardPattern()) => true // don't skip when binding an interesting symbol! + case Star(WildcardPattern()) => true + case x: Ident => treeInfo.isVarPattern(x) + case Alternative(ps) => ps forall unapply + case EmptyTree => true + case _ => false + } + } + + object PatternBoundToUnderscore { + def unapply(pat: Tree): Boolean = pat match { + case Bind(nme.WILDCARD, _) => true // don't skip when binding an interesting symbol! + case Ident(nme.WILDCARD) => true + case Alternative(ps) => ps forall unapply + case Typed(PatternBoundToUnderscore(), _) => true + case _ => false + } + } + object SymbolBound { def unapply(tree: Tree): Option[(Symbol, Tree)] = tree match { case Bind(_, expr) if hasSym(tree) => Some(tree.symbol -> expr) @@ -86,10 +110,8 @@ trait MatchTranslation { // example check: List[Int] <:< ::[Int] private def extractorStep(): TranslationStep = { - import extractor.{ paramType, treeMaker } - if (!extractor.isTyped) - ErrorUtils.issueNormalTypeError(tree, "Could not typecheck extractor call: "+ extractor)(context) - + def paramType = extractor.aligner.wholeType + import extractor.treeMaker // chain a type-testing extractor before the actual extractor call // it tests the type, checks the outer pointer and casts to the expected type // TODO: the outer check is mandated by the spec for case classes, but we do it for user-defined unapplies as well [SPEC] @@ -355,36 +377,20 @@ trait MatchTranslation { object ExtractorCall { // TODO: check unargs == args def apply(tree: Tree): ExtractorCall = tree match { - case UnApply(unfun, args) => new ExtractorCallRegular(unfun, args) // extractor - case Apply(fun, args) => new ExtractorCallProd(fun, args) // case class + case UnApply(unfun, args) => new ExtractorCallRegular(alignPatterns(tree), unfun, args) // extractor + case Apply(fun, args) => new ExtractorCallProd(alignPatterns(tree), fun, args) // case class } } - abstract class ExtractorCall { + abstract class ExtractorCall(val aligner: PatternAligned) { + import aligner._ def fun: Tree def args: List[Tree] - val nbSubPats = args.length - val starLength = if (hasStar) 1 else 0 - val nonStarLength = args.length - starLength - - // everything okay, captain? - def isTyped: Boolean - def isSeq: Boolean - - private def hasStar = nbSubPats > 0 && isStar(args.last) - private def isNonEmptySeq = nbSubPats > 0 && isSeq - - /** This is special cased so that a single pattern will accept any extractor - * result, even if it's a tuple (SI-6675) - */ - def isSingle = nbSubPats == 1 && !isSeq - - // to which type should the previous binder be casted? - def paramType : Type - - protected def rawSubPatTypes: List[Type] - protected def resultType: Type + // don't go looking for selectors if we only expect one pattern + def rawSubPatTypes = aligner.extractedTypes + def resultInMonad = if (isBool) UnitTpe else typeOfMemberNamedGet(resultType) + def resultType = fun.tpe.finalResultType /** Create the TreeMaker that embodies this extractor call * @@ -407,24 +413,14 @@ trait MatchTranslation { lazy val ignoredSubPatBinders: Set[Symbol] = subPatBinders zip args collect { case (b, PatternBoundToUnderscore()) => b } toSet // do repeated-parameter expansion to match up with the expected number of arguments (in casu, subpatterns) - private def nonStarSubPatTypes = formalTypes(rawInit :+ repeatedType, nonStarLength) + private def nonStarSubPatTypes = aligner.typedNonStarPatterns map (_.tpe) - def subPatTypes: List[Type] = ( - if (rawSubPatTypes.isEmpty || !isSeq) rawSubPatTypes - else if (hasStar) nonStarSubPatTypes :+ sequenceType - else nonStarSubPatTypes - ) - - private def rawGet = typeOfMemberNamedGetOrSelf(resultType) - private def rawInit = rawSubPatTypes dropRight 1 - protected def sequenceType = typeOfLastSelectorOrSelf(rawGet) - protected def elementType = elementTypeOfLastSelectorOrSelf(rawGet) - protected def repeatedType = scalaRepeatedType(elementType) + def subPatTypes: List[Type] = typedPatterns map (_.tpe) - // rawSubPatTypes.last is the Seq, thus there are `rawSubPatTypes.length - 1` non-seq elements in the tuple - protected def firstIndexingBinder = rawSubPatTypes.length - 1 - protected def lastIndexingBinder = nbSubPats - 1 - starLength - protected def expectedLength = lastIndexingBinder - firstIndexingBinder + 1 + // there are `productArity` non-seq elements in the tuple. + protected def firstIndexingBinder = productArity + protected def expectedLength = elementArity + protected def lastIndexingBinder = totalArity - starArity - 1 private def productElemsToN(binder: Symbol, n: Int): List[Tree] = 1 to n map tupleSel(binder) toList private def genTake(binder: Symbol, n: Int): List[Tree] = (0 until n).toList map (codegen index seqTree(binder)) @@ -438,12 +434,12 @@ trait MatchTranslation { // referenced by `binder` protected def subPatRefsSeq(binder: Symbol): List[Tree] = { def lastTrees: List[Tree] = ( - if (!hasStar) Nil + if (!aligner.isStar) Nil else if (expectedLength == 0) seqTree(binder) :: Nil else genDrop(binder, expectedLength) ) // this error-condition has already been checked by checkStarPatOK: - // if(isSeq) assert(firstIndexingBinder + nbIndexingIndices + (if(lastIsStar) 1 else 0) == nbSubPats, "(resultInMonad, ts, subPatTypes, subPats)= "+(resultInMonad, ts, subPatTypes, subPats)) + // if(isSeq) assert(firstIndexingBinder + nbIndexingIndices + (if(lastIsStar) 1 else 0) == totalArity, "(resultInMonad, ts, subPatTypes, subPats)= "+(resultInMonad, ts, subPatTypes, subPats)) // [1] there are `firstIndexingBinder` non-seq tuple elements preceding the Seq // [2] then we have to index the binder that represents the sequence for the remaining subpatterns, except for... @@ -457,8 +453,10 @@ trait MatchTranslation { // the trees that select the subpatterns on the extractor's result, referenced by `binder` // require (nbSubPats > 0 && (!lastIsStar || isSeq)) - protected def subPatRefs(binder: Symbol): List[Tree] = - if (isNonEmptySeq) subPatRefsSeq(binder) else productElemsToN(binder, nbSubPats) + protected def subPatRefs(binder: Symbol): List[Tree] = ( + if (totalArity > 0 && isSeq) subPatRefsSeq(binder) + else productElemsToN(binder, totalArity) + ) private def compareInts(t1: Tree, t2: Tree) = gen.mkMethodCall(termMember(ScalaPackage, "math"), TermName("signum"), Nil, (t1 INT_- t2) :: Nil) @@ -478,7 +476,7 @@ trait MatchTranslation { // when the last subpattern is a wildcard-star the expectedLength is but a lower bound // (otherwise equality is required) def compareOp: (Tree, Tree) => Tree = - if (hasStar) _ INT_>= _ + if (aligner.isStar) _ INT_>= _ else _ INT_== _ // `if (binder != null && $checkExpectedLength [== | >=] 0) then else zero` @@ -487,26 +485,14 @@ trait MatchTranslation { def checkedLength: Option[Int] = // no need to check unless it's an unapplySeq and the minimal length is non-trivially satisfied - if (!isSeq || expectedLength < starLength) None + if (!isSeq || expectedLength < starArity) None else Some(expectedLength) } // TODO: to be called when there's a def unapplyProd(x: T): U // U must have N members _1,..., _N -- the _i are type checked, call their type Ti, // for now only used for case classes -- pretending there's an unapplyProd that's the identity (and don't call it) - class ExtractorCallProd(val fun: Tree, val args: List[Tree]) extends ExtractorCall { - private def constructorTp = fun.tpe - - def isTyped = fun.isTyped - - // to which type should the previous binder be casted? - def paramType = constructorTp.finalResultType - def resultType = fun.tpe.finalResultType - - def isSeq = isVarArgTypes(rawSubPatTypes) - - protected def rawSubPatTypes = constructorTp.paramTypes - + class ExtractorCallProd(aligner: PatternAligned, val fun: Tree, val args: List[Tree]) extends ExtractorCall(aligner) { /** Create the TreeMaker that embodies this extractor call * * `binder` has been casted to `paramType` if necessary @@ -535,20 +521,11 @@ trait MatchTranslation { if (accessors isDefinedAt (i-1)) REF(binder) DOT accessors(i-1) else codegen.tupleSel(binder)(i) // this won't type check for case classes, as they do not inherit ProductN } - - override def toString() = s"ExtractorCallProd($fun:${fun.tpe} / ${fun.symbol} / args=$args)" } - class ExtractorCallRegular(extractorCallIncludingDummy: Tree, val args: List[Tree]) extends ExtractorCall { + class ExtractorCallRegular(aligner: PatternAligned, extractorCallIncludingDummy: Tree, val args: List[Tree]) extends ExtractorCall(aligner) { val Unapplied(fun) = extractorCallIncludingDummy - def tpe = fun.tpe - def paramType = firstParamType(tpe) - def resultType = tpe.finalResultType - def isTyped = (tpe ne NoType) && fun.isTyped && (resultInMonad ne ErrorType) - def isSeq = fun.symbol.name == nme.unapplySeq - def isBool = resultType =:= BooleanTpe - /** Create the TreeMaker that embodies this extractor call * * `binder` has been casted to `paramType` if necessary @@ -571,7 +548,7 @@ trait MatchTranslation { ExtractorTreeMaker(extractorApply, lengthGuard(binder), binder)( subPatBinders, subPatRefs(binder), - isBool, + aligner.isBool, checkedLength, patBinderOrCasted, ignoredSubPatBinders @@ -583,9 +560,9 @@ trait MatchTranslation { else super.seqTree(binder) // the trees that select the subpatterns on the extractor's result, referenced by `binder` - // require (nbSubPats > 0 && (!lastIsStar || isSeq)) + // require (totalArity > 0 && (!lastIsStar || isSeq)) override protected def subPatRefs(binder: Symbol): List[Tree] = - if (isSingle) REF(binder) :: Nil // special case for extractors + if (aligner.isSingle) REF(binder) :: Nil // special case for extractors else super.subPatRefs(binder) protected def spliceApply(binder: Symbol): Tree = { @@ -606,40 +583,7 @@ trait MatchTranslation { splice transform extractorCallIncludingDummy } - // what's the extractor's result type in the monad? It is the type of its nullary member `get`. - protected lazy val resultInMonad: Type = if (isBool) UnitTpe else typeOfMemberNamedGet(resultType) - - protected lazy val rawSubPatTypes = ( - if (isBool) Nil - else if (isSingle) resultInMonad :: Nil // don't go looking for selectors if we only expect one pattern - else typesOfSelectorsOrSelf(resultInMonad) - ) - - override def toString() = s"ExtractorCallRegular($fun: $tpe / ${fun.symbol})" - } - - /** A conservative approximation of which patterns do not discern anything. - * They are discarded during the translation. - */ - object WildcardPattern { - def unapply(pat: Tree): Boolean = pat match { - case Bind(nme.WILDCARD, WildcardPattern()) => true // don't skip when binding an interesting symbol! - case Star(WildcardPattern()) => true - case x: Ident => treeInfo.isVarPattern(x) - case Alternative(ps) => ps forall unapply - case EmptyTree => true - case _ => false - } - } - - object PatternBoundToUnderscore { - def unapply(pat: Tree): Boolean = pat match { - case Bind(nme.WILDCARD, _) => true // don't skip when binding an interesting symbol! - case Ident(nme.WILDCARD) => true - case Alternative(ps) => ps forall unapply - case Typed(PatternBoundToUnderscore(), _) => true - case _ => false - } + override def rawSubPatTypes = aligner.extractor.varargsTypes } } } diff --git a/src/compiler/scala/tools/nsc/transform/patmat/MatchTreeMaking.scala b/src/compiler/scala/tools/nsc/transform/patmat/MatchTreeMaking.scala index 7df03044aa..a80f158949 100644 --- a/src/compiler/scala/tools/nsc/transform/patmat/MatchTreeMaking.scala +++ b/src/compiler/scala/tools/nsc/transform/patmat/MatchTreeMaking.scala @@ -395,8 +395,10 @@ trait MatchTreeMaking extends MatchCodeGen with Debugging { debug.patmat("TTTM"+((prevBinder, extractorArgTypeTest, testedBinder, expectedTp, nextBinderTp))) lazy val outerTestNeeded = ( - !((expectedTp.prefix eq NoPrefix) || expectedTp.prefix.typeSymbol.isPackageClass) - && needsOuterTest(expectedTp, testedBinder.info, matchOwner)) + (expectedTp.prefix ne NoPrefix) + && !expectedTp.prefix.typeSymbol.isPackageClass + && needsOuterTest(expectedTp, testedBinder.info, matchOwner) + ) // the logic to generate the run-time test that follows from the fact that // a `prevBinder` is expected to have type `expectedTp` @@ -406,44 +408,52 @@ trait MatchTreeMaking extends MatchCodeGen with Debugging { def renderCondition(cs: TypeTestCondStrategy): cs.Result = { import cs._ - def default = - // do type test first to ensure we won't select outer on null - if (outerTestNeeded) and(typeTest(testedBinder, expectedTp), outerTest(testedBinder, expectedTp)) - else typeTest(testedBinder, expectedTp) - // propagate expected type def expTp(t: Tree): t.type = t setType expectedTp + def testedWide = testedBinder.info.widen + def expectedWide = expectedTp.widen + def isAnyRef = testedWide <:< AnyRefTpe + def isAsExpected = testedWide <:< expectedTp + def isExpectedPrimitiveType = isAsExpected && isPrimitiveValueType(expectedTp) + def isExpectedReferenceType = isAsExpected && (expectedTp <:< AnyRefTpe) + def mkNullTest = nonNullTest(testedBinder) + def mkOuterTest = outerTest(testedBinder, expectedTp) + def mkTypeTest = typeTest(testedBinder, expectedWide) + + def mkEqualsTest(lhs: Tree): cs.Result = equalsTest(lhs, testedBinder) + def mkEqTest(lhs: Tree): cs.Result = eqTest(lhs, testedBinder) + def addOuterTest(res: cs.Result): cs.Result = if (outerTestNeeded) and(res, mkOuterTest) else res + + // If we conform to expected primitive type: + // it cannot be null and cannot have an outer pointer. No further checking. + // If we conform to expected reference type: + // have to test outer and non-null + // If we do not conform to expected type: + // have to test type and outer (non-null is implied by successful type test) + def mkDefault = ( + if (isExpectedPrimitiveType) tru + else addOuterTest( + if (isExpectedReferenceType) mkNullTest + else mkTypeTest + ) + ) + // true when called to type-test the argument to an extractor // don't do any fancy equality checking, just test the type - if (extractorArgTypeTest) default + // TODO: verify that we don't need to special-case Array + // I think it's okay: + // - the isInstanceOf test includes a test for the element type + // - Scala's arrays are invariant (so we don't drop type tests unsoundly) + if (extractorArgTypeTest) mkDefault else expectedTp match { - // TODO: [SPEC] the spec requires `eq` instead of `==` for singleton types - // this implies sym.isStable - case SingleType(_, sym) => and(equalsTest(gen.mkAttributedQualifier(expectedTp), testedBinder), typeTest(testedBinder, expectedTp.widen)) - // must use == to support e.g. List() == Nil - case ThisType(sym) if sym.isModule => and(equalsTest(CODE.REF(sym), testedBinder), typeTest(testedBinder, expectedTp.widen)) - case ConstantType(Constant(null)) if testedBinder.info.widen <:< AnyRefTpe - => eqTest(expTp(CODE.NULL), testedBinder) - case ConstantType(const) => equalsTest(expTp(Literal(const)), testedBinder) - case ThisType(sym) => eqTest(expTp(This(sym)), testedBinder) - - // TODO: verify that we don't need to special-case Array - // I think it's okay: - // - the isInstanceOf test includes a test for the element type - // - Scala's arrays are invariant (so we don't drop type tests unsoundly) - case _ if testedBinder.info.widen <:< expectedTp => - // if the expected type is a primitive value type, it cannot be null and it cannot have an outer pointer - // since the types conform, no further checking is required - if (isPrimitiveValueType(expectedTp)) tru - // have to test outer and non-null only when it's a reference type - else if (expectedTp <:< AnyRefTpe) { - // do non-null check first to ensure we won't select outer on null - if (outerTestNeeded) and(nonNullTest(testedBinder), outerTest(testedBinder, expectedTp)) - else nonNullTest(testedBinder) - } else default - - case _ => default + // TODO: [SPEC] the spec requires `eq` instead of `==` for singleton types - this implies sym.isStable + case SingleType(_, sym) => and(mkEqualsTest(gen.mkAttributedQualifier(expectedTp)), mkTypeTest) + case ThisType(sym) if sym.isModule => and(mkEqualsTest(CODE.REF(sym)), mkTypeTest) // must use == to support e.g. List() == Nil + case ConstantType(Constant(null)) if isAnyRef => mkEqTest(expTp(CODE.NULL)) + case ConstantType(const) => mkEqualsTest(expTp(Literal(const))) + case ThisType(sym) => mkEqTest(expTp(This(sym))) + case _ => mkDefault } } diff --git a/src/compiler/scala/tools/nsc/transform/patmat/PatternExpander.scala b/src/compiler/scala/tools/nsc/transform/patmat/PatternExpander.scala new file mode 100644 index 0000000000..e84ccbf754 --- /dev/null +++ b/src/compiler/scala/tools/nsc/transform/patmat/PatternExpander.scala @@ -0,0 +1,155 @@ +/* NSC -- new Scala compiler + * Copyright 2005-2013 LAMP/EPFL + * @author Paul Phillips + */ + +package scala +package tools +package nsc +package transform +package patmat + +/** An extractor returns: F1, F2, ..., Fi, opt[Seq[E] or E*] + * A case matches: P1, P2, ..., Pj, opt[Seq[E]] + * Put together: P1/F1, P2/F2, ... Pi/Fi, Pi+1/E, Pi+2/E, ... Pj/E, opt[Seq[E]] + * + * Here Pm/Fi is the last pattern to match the fixed arity section. + * + * productArity: the value of i, i.e. the number of non-sequence types in the extractor + * nonStarArity: the value of j, i.e. the number of non-star patterns in the case definition + * elementArity: j - i, i.e. the number of non-star patterns which must match sequence elements + * starArity: 1 or 0 based on whether there is a star (sequence-absorbing) pattern + * totalArity: nonStarArity + starArity, i.e. the number of patterns in the case definition + * + * Note that productArity is a function only of the extractor, and + * nonStar/star/totalArity are all functions of the patterns. The key + * value for aligning and typing the patterns is elementArity, as it + * is derived from both sets of information. + */ +trait PatternExpander[Pattern, Type] { + /** You'll note we're not inside the cake. "Pattern" and "Type" are + * arbitrary types here, and NoPattern and NoType arbitrary values. + */ + def NoPattern: Pattern + def NoType: Type + + /** It's not optimal that we're carrying both sequence and repeated + * type here, but the implementation requires more unraveling before + * it can be avoided. + * + * sequenceType is Seq[T], elementType is T, repeatedType is T*. + */ + sealed case class Repeated(sequenceType: Type, elementType: Type, repeatedType: Type) { + def exists = elementType != NoType + + def elementList = if (exists) elementType :: Nil else Nil + def sequenceList = if (exists) sequenceType :: Nil else Nil + def repeatedList = if (exists) repeatedType :: Nil else Nil + + override def toString = s"${elementType}*" + } + object NoRepeated extends Repeated(NoType, NoType, NoType) { + override def toString = "<none>" + } + + final case class Patterns(fixed: List[Pattern], star: Pattern) { + def hasStar = star != NoPattern + def starArity = if (hasStar) 1 else 0 + def nonStarArity = fixed.length + def totalArity = nonStarArity + starArity + def starPatterns = if (hasStar) star :: Nil else Nil + def all = fixed ::: starPatterns + + override def toString = all mkString ", " + } + + /** An 'extractor' can be a case class or an unapply or unapplySeq method. + * Decoding what it is that they extract takes place before we arrive here, + * so that this class can concentrate only on the relationship between + * patterns and types. + * + * In a case class, the class is the unextracted type and the fixed and + * repeated types are derived from its constructor parameters. + * + * In an unapply, this is reversed: the parameter to the unapply is the + * unextracted type, and the other types are derived based on the return + * type of the unapply method. + * + * In other words, this case class and unapply are encoded the same: + * + * case class Foo(x: Int, y: Int, zs: Char*) + * def unapplySeq(x: Foo): Option[(Int, Int, Seq[Char])] + * + * Both are Extractor(Foo, Int :: Int :: Nil, Repeated(Seq[Char], Char, Char*)) + * + * @param whole The type in its unextracted form + * @param fixed The non-sequence types which are extracted + * @param repeated The sequence type which is extracted + */ + final case class Extractor(whole: Type, fixed: List[Type], repeated: Repeated) { + require(whole != NoType, s"expandTypes($whole, $fixed, $repeated)") + + def productArity = fixed.length + def hasSeq = repeated.exists + def elementType = repeated.elementType + def sequenceType = repeated.sequenceType + def allTypes = fixed ::: repeated.sequenceList + def varargsTypes = fixed ::: repeated.repeatedList + def isErroneous = allTypes contains NoType + + private def typeStrings = fixed.map("" + _) ::: ( if (hasSeq) List("" + repeated) else Nil ) + + def offeringString = if (isErroneous) "<error>" else typeStrings match { + case Nil => "Boolean" + case tp :: Nil => tp + case tps => tps.mkString("(", ", ", ")") + } + override def toString = "%s => %s".format(whole, offeringString) + } + + final case class TypedPat(pat: Pattern, tpe: Type) { + override def toString = s"$pat: $tpe" + } + + /** If elementArity is... + * 0: A perfect match between extractor and the fixed patterns. + * If there is a star pattern it will match any sequence. + * > 0: There are more patterns than products. There will have to be a + * sequence which can populate at least <elementArity> patterns. + * < 0: There are more products than patterns: compile time error. + */ + final case class Aligned(patterns: Patterns, extractor: Extractor) { + def elementArity = patterns.nonStarArity - productArity + def productArity = extractor.productArity + def starArity = patterns.starArity + def totalArity = patterns.totalArity + + def wholeType = extractor.whole + def sequenceType = extractor.sequenceType + def productTypes = extractor.fixed + def extractedTypes = extractor.allTypes + def typedNonStarPatterns = products ::: elements + def typedPatterns = typedNonStarPatterns ::: stars + + def isBool = !isSeq && productArity == 0 + def isSingle = !isSeq && totalArity == 1 + def isStar = patterns.hasStar + def isSeq = extractor.hasSeq + + private def typedAsElement(pat: Pattern) = TypedPat(pat, extractor.elementType) + private def typedAsSequence(pat: Pattern) = TypedPat(pat, extractor.sequenceType) + private def productPats = patterns.fixed take productArity + private def elementPats = patterns.fixed drop productArity + private def products = (productPats, productTypes).zipped map TypedPat + private def elements = elementPats map typedAsElement + private def stars = patterns.starPatterns map typedAsSequence + + override def toString = s""" + |Aligned { + | patterns $patterns + | extractor $extractor + | arities $productArity/$elementArity/$starArity // product/element/star + | typed ${typedPatterns mkString ", "} + |}""".stripMargin.trim + } +} diff --git a/src/compiler/scala/tools/nsc/transform/patmat/PatternMatching.scala b/src/compiler/scala/tools/nsc/transform/patmat/PatternMatching.scala index 394ba98f17..f6c960d089 100644 --- a/src/compiler/scala/tools/nsc/transform/patmat/PatternMatching.scala +++ b/src/compiler/scala/tools/nsc/transform/patmat/PatternMatching.scala @@ -34,7 +34,8 @@ import scala.reflect.internal.util.Position * - recover GADT typing by locally inserting implicit witnesses to type equalities derived from the current case, and considering these witnesses during subtyping (?) * - recover exhaustivity/unreachability of user-defined extractors by partitioning the types they match on using an HList or similar type-level structure */ -trait PatternMatching extends Transform with TypingTransformers +trait PatternMatching extends Transform + with TypingTransformers with Debugging with Interface with MatchTranslation @@ -45,7 +46,8 @@ trait PatternMatching extends Transform with TypingTransformers with Solving with MatchAnalysis with MatchOptimization - with MatchWarnings { + with MatchWarnings + with ScalacPatternExpanders { import global._ val phaseName: String = "patmat" diff --git a/src/compiler/scala/tools/nsc/transform/patmat/ScalacPatternExpanders.scala b/src/compiler/scala/tools/nsc/transform/patmat/ScalacPatternExpanders.scala new file mode 100644 index 0000000000..7858cb5586 --- /dev/null +++ b/src/compiler/scala/tools/nsc/transform/patmat/ScalacPatternExpanders.scala @@ -0,0 +1,154 @@ +/* NSC -- new Scala compiler + * Copyright 2005-2013 LAMP/EPFL + * @author Paul Phillips + */ + +package scala +package tools +package nsc +package transform +package patmat + +/** This is scalac-specific logic layered on top of the scalac-agnostic + * "matching products to patterns" logic defined in PatternExpander. + */ +trait ScalacPatternExpanders { + val global: Global + + import global._ + import definitions._ + import treeInfo._ + + type PatternAligned = ScalacPatternExpander#Aligned + + implicit class AlignedOps(val aligned: PatternAligned) { + import aligned._ + def expectedTypes = typedPatterns map (_.tpe) + def unexpandedFormals = extractor.varargsTypes + } + trait ScalacPatternExpander extends PatternExpander[Tree, Type] { + def NoPattern = EmptyTree + def NoType = global.NoType + + def newPatterns(patterns: List[Tree]): Patterns = patterns match { + case init :+ last if isStar(last) => Patterns(init, last) + case _ => Patterns(patterns, NoPattern) + } + def elementTypeOf(tpe: Type) = { + val seq = repeatedToSeq(tpe) + + ( typeOfMemberNamedHead(seq) + orElse typeOfMemberNamedApply(seq) + orElse definitions.elementType(ArrayClass, seq) + ) + } + def newExtractor(whole: Type, fixed: List[Type], repeated: Repeated): Extractor = + logResult(s"newExtractor($whole, $fixed, $repeated")(Extractor(whole, fixed, repeated)) + + // Turn Seq[A] into Repeated(Seq[A], A, A*) + def repeatedFromSeq(seqType: Type): Repeated = { + val elem = elementTypeOf(seqType) + val repeated = scalaRepeatedType(elem) + + Repeated(seqType, elem, repeated) + } + // Turn A* into Repeated(Seq[A], A, A*) + def repeatedFromVarargs(repeated: Type): Repeated = + Repeated(repeatedToSeq(repeated), repeatedToSingle(repeated), repeated) + + /** In this case we are basing the pattern expansion on a case class constructor. + * The argument is the MethodType carried by the primary constructor. + */ + def applyMethodTypes(method: Type): Extractor = { + val whole = method.finalResultType + + method.paramTypes match { + case init :+ last if isScalaRepeatedParamType(last) => newExtractor(whole, init, repeatedFromVarargs(last)) + case tps => newExtractor(whole, tps, NoRepeated) + } + } + + /** In this case, expansion is based on an unapply or unapplySeq method. + * Unfortunately the MethodType does not carry the information of whether + * it was unapplySeq, so we have to funnel that information in separately. + */ + def unapplyMethodTypes(method: Type, isSeq: Boolean): Extractor = { + val whole = firstParamType(method) + val result = method.finalResultType + val expanded = ( + if (result =:= BooleanTpe) Nil + else typeOfMemberNamedGet(result) match { + case rawGet if !hasSelectors(rawGet) => rawGet :: Nil + case rawGet => typesOfSelectors(rawGet) + } + ) + expanded match { + case init :+ last if isSeq => newExtractor(whole, init, repeatedFromSeq(last)) + case tps => newExtractor(whole, tps, NoRepeated) + } + } + } + object alignPatterns extends ScalacPatternExpander { + /** Converts a T => (A, B, C) extractor to a T => ((A, B, CC)) extractor. + */ + def tupleExtractor(extractor: Extractor): Extractor = + extractor.copy(fixed = tupleType(extractor.fixed) :: Nil) + + private def validateAligned(tree: Tree, aligned: Aligned): Aligned = { + import aligned._ + + def owner = tree.symbol.owner + def offering = extractor.offeringString + def symString = tree.symbol.fullLocationString + def offerString = if (extractor.isErroneous) "" else s" offering $offering" + def arityExpected = ( if (extractor.hasSeq) "at least " else "" ) + productArity + + def err(msg: String) = currentUnit.error(tree.pos, msg) + def warn(msg: String) = currentUnit.warning(tree.pos, msg) + def arityError(what: String) = err(s"$what patterns for $owner$offerString: expected $arityExpected, found $totalArity") + + if (isStar && !isSeq) + err("Star pattern must correspond with varargs or unapplySeq") + else if (elementArity < 0) + arityError("not enough") + else if (elementArity > 0 && !extractor.hasSeq) + arityError("too many") + + aligned + } + + def apply(sel: Tree, args: List[Tree]): Aligned = { + val fn = sel match { + case Unapplied(fn) => fn + case _ => sel + } + val patterns = newPatterns(args) + val isSeq = sel.symbol.name == nme.unapplySeq + val isUnapply = sel.symbol.name == nme.unapply + val extractor = sel.symbol.name match { + case nme.unapply => unapplyMethodTypes(fn.tpe, isSeq = false) + case nme.unapplySeq => unapplyMethodTypes(fn.tpe, isSeq = true) + case _ => applyMethodTypes(fn.tpe) + } + + /** Rather than let the error that is SI-6675 pollute the entire matching + * process, we will tuple the extractor before creation Aligned so that + * it contains known good values. + */ + def productArity = extractor.productArity + def acceptMessage = if (extractor.isErroneous) "" else s" to hold ${extractor.offeringString}" + val requiresTupling = isUnapply && patterns.totalArity == 1 && productArity > 1 + + if (settings.lint && requiresTupling && effectivePatternArity(args) == 1) + currentUnit.warning(sel.pos, s"${sel.symbol.owner} expects $productArity patterns$acceptMessage but crushing into $productArity-tuple to fit single pattern (SI-6675)") + + val normalizedExtractor = if (requiresTupling) tupleExtractor(extractor) else extractor + validateAligned(fn, Aligned(patterns, normalizedExtractor)) + } + + def apply(tree: Tree): Aligned = tree match { + case Apply(fn, args) => apply(fn, args) + case UnApply(fn, args) => apply(fn, args) + } + } +} diff --git a/src/compiler/scala/tools/nsc/typechecker/ContextErrors.scala b/src/compiler/scala/tools/nsc/typechecker/ContextErrors.scala index cd6b77404d..4d0eda2377 100644 --- a/src/compiler/scala/tools/nsc/typechecker/ContextErrors.scala +++ b/src/compiler/scala/tools/nsc/typechecker/ContextErrors.scala @@ -625,8 +625,7 @@ trait ContextErrors { setError(tree) } - def CaseClassConstructorError(tree: Tree) = { - val baseMessage = tree.symbol + " is not a case class constructor, nor does it have an unapply/unapplySeq method" + def CaseClassConstructorError(tree: Tree, baseMessage: String) = { val addendum = directUnapplyMember(tree.symbol.info) match { case sym if hasMultipleNonImplicitParamLists(sym) => s"\nNote: ${sym.defString} exists in ${tree.symbol}, but it cannot be used as an extractor due to its second non-implicit parameter list" case _ => "" diff --git a/src/compiler/scala/tools/nsc/typechecker/PatternTypers.scala b/src/compiler/scala/tools/nsc/typechecker/PatternTypers.scala index 069d6d5fb2..41c656f8ce 100644 --- a/src/compiler/scala/tools/nsc/typechecker/PatternTypers.scala +++ b/src/compiler/scala/tools/nsc/typechecker/PatternTypers.scala @@ -78,26 +78,34 @@ trait PatternTypers { // Do some ad-hoc overloading resolution and update the tree's symbol and type // do not update the symbol if the tree's symbol's type does not define an unapply member // (e.g. since it's some method that returns an object with an unapply member) - val fun = inPlaceAdHocOverloadingResolution(fun0)(hasUnapplyMember) - def caseClass = fun.tpe.typeSymbol.linkedClassOfClass + val fun = inPlaceAdHocOverloadingResolution(fun0)(hasUnapplyMember) + val caseClass = fun.tpe.typeSymbol.linkedClassOfClass + val member = unapplyMember(fun.tpe) + def resultType = (fun.tpe memberType member).finalResultType + def isEmptyType = resultOfMatchingMethod(resultType, nme.isEmpty)() + def isOkay = ( + resultType.isErroneous + || (resultType <:< BooleanTpe) + || (isEmptyType <:< BooleanTpe) + || member.isMacro + || member.isOverloaded // the whole overloading situation is over the rails + ) // Dueling test cases: pos/overloaded-unapply.scala, run/case-class-23.scala, pos/t5022.scala // A case class with 23+ params has no unapply method. - // A case class constructor be overloaded with unapply methods in the companion. - if (caseClass.isCase && !unapplyMember(fun.tpe).isOverloaded) + // A case class constructor may be overloaded with unapply methods in the companion. + if (caseClass.isCase && !member.isOverloaded) logResult(s"convertToCaseConstructor($fun, $caseClass, pt=$pt)")(convertToCaseConstructor(fun, caseClass, pt)) - else if (hasUnapplyMember(fun)) + else if (!reallyExists(member)) + CaseClassConstructorError(fun, s"${fun.symbol} is not a case class, nor does it have an unapply/unapplySeq member") + else if (isOkay) fun + else if (isEmptyType == NoType) + CaseClassConstructorError(fun, s"an unapply result must have a member `def isEmpty: Boolean") else - CaseClassConstructorError(fun) + CaseClassConstructorError(fun, s"an unapply result must have a member `def isEmpty: Boolean (found: def isEmpty: $isEmptyType)") } - def expectedPatternTypes(fun: Tree, args: List[Tree]): List[Type] = - newExtractorShape(fun, args).expectedPatternTypes - - def typedPatternArgs(fun: Tree, args: List[Tree], mode: Mode): List[Tree] = - typedArgsForFormals(args, newExtractorShape(fun, args).formals, mode) - def typedArgsForFormals(args: List[Tree], formals: List[Type], mode: Mode): List[Tree] = { def typedArgWithFormal(arg: Tree, pt: Type) = { val newMode = if (isByNameParamType(pt)) mode.onlySticky else mode.onlySticky | BYVALmode @@ -158,109 +166,6 @@ trait PatternTypers { case _ => wrapClassTagUnapply(treeTyped, extractor, tpe) } } - - def newExtractorShape(fun: Tree, args: List[Tree]): ExtractorShape = ExtractorShape(fun, args) - - case class CaseClassInfo(clazz: Symbol, classType: Type) { - def constructor = clazz.primaryConstructor - def constructorType = classType.prefix memberType clazz memberType constructor - def accessors = clazz.caseFieldAccessors - } - object NoCaseClassInfo extends CaseClassInfo(NoSymbol, NoType) { - override def toString = "NoCaseClassInfo" - } - - case class UnapplyMethodInfo(unapply: Symbol, tpe: Type) { - def name = unapply.name - def isUnapplySeq = name == nme.unapplySeq - def unapplyType = tpe memberType method - def resultType = tpe.finalResultType - def method = unapplyMember(tpe) - def paramType = firstParamType(unapplyType) - def rawGet = if (isBool) UnitTpe else typeOfMemberNamedGetOrSelf(resultType) - def rawTypes = if (isBool) Nil else typesOfSelectorsOrSelf(rawGet) - def isBool = resultType =:= BooleanTpe // aka "Tuple0" or "Option[Unit]" - } - - object NoUnapplyMethodInfo extends UnapplyMethodInfo(NoSymbol, NoType) { - override def toString = "NoUnapplyMethodInfo" - } - - case class ExtractorShape(fun: Tree, args: List[Tree]) { - def pos = fun.pos - private def symbol = fun.symbol - private def tpe = fun.tpe - - val ccInfo = tpe.typeSymbol.linkedClassOfClass match { - case clazz if clazz.isCase => CaseClassInfo(clazz, tpe) - case _ => NoCaseClassInfo - } - val exInfo = UnapplyMethodInfo(symbol, tpe) - import exInfo.{ rawGet, rawTypes, isUnapplySeq } - - override def toString = s"ExtractorShape($fun, $args)" - - def unapplyMethod = exInfo.method - def unapplyType = exInfo.unapplyType - def unapplyParamType = exInfo.paramType - def enclClass = symbol.enclClass - - // TODO - merge these. The difference between these two methods is that expectedPatternTypes - // expands the list of types so it is the same length as the number of patterns, whereas formals - // leaves the varargs type unexpanded. - def formals = ( - if (isUnapplySeq) productTypes :+ varargsType - else if (elementArity == 0) productTypes - else if (isSingle) squishIntoOne() - else wrongArity(patternFixedArity) - ) - def expectedPatternTypes = elementArity match { - case 0 => productTypes - case _ if elementArity > 0 && isUnapplySeq => productTypes ::: elementTypes - case _ if productArity > 1 && patternFixedArity == 1 => squishIntoOne() - case _ => wrongArity(patternFixedArity) - } - - def elementType = elementTypeOfLastSelectorOrSelf(rawGet) - - private def hasBogusExtractor = directUnapplyMember(tpe).exists && !unapplyMethod.exists - private def expectedArity = "" + productArity + ( if (isUnapplySeq) "+" else "") - private def wrongArityMsg(n: Int) = ( - if (hasBogusExtractor) s"$enclClass does not define a valid extractor method" - else s"wrong number of patterns for $enclClass offering $rawTypes_s: expected $expectedArity, found $n" - ) - private def rawTypes_s = rawTypes match { - case Nil => "()" - case tp :: Nil => "" + tp - case tps => tps.mkString("(", ", ", ")") - } - - private def err(msg: String) = { unit.error(pos, msg) ; throw new TypeError(msg) } - private def wrongArity(n: Int) = err(wrongArityMsg(n)) - - def squishIntoOne() = { - if (settings.lint) - unit.warning(pos, s"$enclClass expects $expectedArity patterns to hold $rawGet but crushing into $productArity-tuple to fit single pattern (SI-6675)") - - rawGet :: Nil - } - // elementArity is the number of non-sequence patterns minus the - // the number of non-sequence product elements returned by the extractor. - // If it is zero, there is a perfect match between those parts, and - // if there is a wildcard star it will match any sequence. - // If it is positive, there are more patterns than products, - // so a sequence will have to fill in the elements. If it is negative, - // there are more products than patterns, which is a compile time error. - def elementArity = patternFixedArity - productArity - def patternFixedArity = treeInfo effectivePatternArity args - def productArity = productTypes.size - def isSingle = !isUnapplySeq && (patternFixedArity == 1) - - def productTypes = if (isUnapplySeq) rawTypes dropRight 1 else rawTypes - def elementTypes = List.fill(elementArity)(elementType) - def varargsType = scalaRepeatedType(elementType) - } - private class VariantToSkolemMap extends TypeMap(trackVariance = true) { private val skolemBuffer = mutable.ListBuffer[TypeSymbol]() @@ -365,10 +270,12 @@ trait PatternTypers { case OverloadedType(_, _) => OverloadedUnapplyError(fun) ; ErrorType case _ => UnapplyWithSingleArgError(fun) ; ErrorType } - val shape = newExtractorShape(fun, args) - import shape.{ unapplyParamType, unapplyType, unapplyMethod } + val unapplyMethod = unapplyMember(fun.tpe) + val unapplyType = fun.tpe memberType unapplyMethod + val unapplyParamType = firstParamType(unapplyType) + def isSeq = unapplyMethod.name == nme.unapplySeq - def extractor = extractorForUncheckedType(shape.pos, unapplyParamType) + def extractor = extractorForUncheckedType(fun.pos, unapplyParamType) def canRemedy = unapplyParamType match { case RefinedType(_, decls) if !decls.isEmpty => false case RefinedType(parents, _) if parents exists isUncheckable => false @@ -400,7 +307,8 @@ trait PatternTypers { // the union of the expected type and the inferred type of the argument to unapply val glbType = glb(ensureFullyDefined(pt) :: unapplyArg.tpe_* :: Nil) val wrapInTypeTest = canRemedy && !(fun1.symbol.owner isNonBottomSubClass ClassTagClass) - val args1 = typedPatternArgs(fun1, args, mode) + val formals = patmat.alignPatterns(fun1, args).unexpandedFormals + val args1 = typedArgsForFormals(args, formals, mode) val result = UnApply(fun1, args1) setPos tree.pos setType glbType if (wrapInTypeTest) diff --git a/src/reflect/scala/reflect/internal/Definitions.scala b/src/reflect/scala/reflect/internal/Definitions.scala index dde3f1e9f7..42c9135495 100644 --- a/src/reflect/scala/reflect/internal/Definitions.scala +++ b/src/reflect/scala/reflect/internal/Definitions.scala @@ -813,46 +813,32 @@ trait Definitions extends api.StandardDefinitions { def byNameType(arg: Type) = appliedType(ByNameParamClass, arg) def iteratorOfType(tp: Type) = appliedType(IteratorClass, tp) def javaRepeatedType(arg: Type) = appliedType(JavaRepeatedParamClass, arg) + def optionType(tp: Type) = appliedType(OptionClass, tp) def scalaRepeatedType(arg: Type) = appliedType(RepeatedParamClass, arg) def seqType(arg: Type) = appliedType(SeqClass, arg) // FYI the long clunky name is because it's really hard to put "get" into the // name of a method without it sounding like the method "get"s something, whereas // this method is about a type member which just happens to be named get. - def typeOfMemberNamedGet(tp: Type) = resultOfMatchingMethod(tp, nme.get)() - def typeOfMemberNamedHead(tp: Type) = resultOfMatchingMethod(tp, nme.head)() - def typeOfMemberNamedApply(tp: Type) = resultOfMatchingMethod(tp, nme.apply)(IntTpe) - def typeOfMemberNamedDrop(tp: Type) = resultOfMatchingMethod(tp, nme.drop)(IntTpe) - def typeOfMemberNamedGetOrSelf(tp: Type) = typeOfMemberNamedGet(tp) orElse tp - def typesOfSelectors(tp: Type) = getterMemberTypes(tp, productSelectors(tp)) - def typesOfCaseAccessors(tp: Type) = getterMemberTypes(tp, tp.typeSymbol.caseFieldAccessors) - - /** If this is a case class, the case field accessors (which may be an empty list.) - * Otherwise, if there are any product selectors, that list. - * Otherwise, a list containing only the type itself. - */ - def typesOfSelectorsOrSelf(tp: Type): List[Type] = ( - if (tp.typeSymbol.isCase) - typesOfCaseAccessors(tp) - else typesOfSelectors(tp) match { - case Nil => tp :: Nil - case tps => tps - } - ) - - /** If the given type has one or more product selectors, the type of the last one. - * Otherwise, the type itself. - */ - def typeOfLastSelectorOrSelf(tp: Type) = typesOfSelectorsOrSelf(tp).last - - def elementTypeOfLastSelectorOrSelf(tp: Type) = { - val last = typeOfLastSelectorOrSelf(tp) - ( typeOfMemberNamedHead(last) - orElse typeOfMemberNamedApply(last) - orElse elementType(ArrayClass, last) - ) + def typeOfMemberNamedGet(tp: Type) = typeArgOfBaseTypeOr(tp, OptionClass)(resultOfMatchingMethod(tp, nme.get)()) + def typeOfMemberNamedHead(tp: Type) = typeArgOfBaseTypeOr(tp, SeqClass)(resultOfMatchingMethod(tp, nme.head)()) + def typeOfMemberNamedApply(tp: Type) = typeArgOfBaseTypeOr(tp, SeqClass)(resultOfMatchingMethod(tp, nme.apply)(IntTpe)) + def typeOfMemberNamedDrop(tp: Type) = typeArgOfBaseTypeOr(tp, SeqClass)(resultOfMatchingMethod(tp, nme.drop)(IntTpe)) + def typesOfSelectors(tp: Type) = getterMemberTypes(tp, productSelectors(tp)) + // SI-8128 Still using the type argument of the base type at Seq/Option if this is an old-style (2.10 compatible) + // extractor to limit exposure to regressions like the reported problem with existentials. + // TODO fix the existential problem in the general case, see test/pending/pos/t8128.scala + private def typeArgOfBaseTypeOr(tp: Type, baseClass: Symbol)(or: => Type): Type = (tp baseType baseClass).typeArgs match { + case x :: Nil => x + case _ => or } + // Can't only check for _1 thanks to pos/t796. + def hasSelectors(tp: Type) = ( + (tp.members containsName nme._1) + && (tp.members containsName nme._2) + ) + /** Returns the method symbols for members _1, _2, ..., _N * which exist in the given type. */ @@ -862,7 +848,9 @@ trait Definitions extends api.StandardDefinitions { case m if m.paramss.nonEmpty => Nil case m => m :: loop(n + 1) } - loop(1) + // Since ErrorType always returns a symbol from a call to member, we + // had better not start looking for _1, _2, etc. expecting it to run out. + if (tpe.isErroneous) Nil else loop(1) } /** If `tp` has a term member `name`, the first parameter list of which diff --git a/src/reflect/scala/reflect/internal/StdNames.scala b/src/reflect/scala/reflect/internal/StdNames.scala index ea6afa7349..a54aa1f6e8 100644 --- a/src/reflect/scala/reflect/internal/StdNames.scala +++ b/src/reflect/scala/reflect/internal/StdNames.scala @@ -686,6 +686,7 @@ trait StdNames { val inlinedEquals: NameType = "inlinedEquals" val isArray: NameType = "isArray" val isDefinedAt: NameType = "isDefinedAt" + val isEmpty: NameType = "isEmpty" val isInstanceOf_ : NameType = "isInstanceOf" val isInstanceOf_Ob : NameType = "$isInstanceOf" val java: NameType = "java" diff --git a/src/reflect/scala/reflect/internal/TreeInfo.scala b/src/reflect/scala/reflect/internal/TreeInfo.scala index 8fdf4dc27a..497a7c91b1 100644 --- a/src/reflect/scala/reflect/internal/TreeInfo.scala +++ b/src/reflect/scala/reflect/internal/TreeInfo.scala @@ -612,8 +612,8 @@ abstract class TreeInfo { def effectivePatternArity(args: List[Tree]): Int = flattenedPatternArgs(args).length def flattenedPatternArgs(args: List[Tree]): List[Tree] = args map unbind match { - case Apply(fun, xs) :: Nil if isTupleSymbol(fun.symbol) => xs - case xs => xs + case build.SyntacticTuple(xs) :: Nil => xs + case xs => xs } // used in the symbols for labeldefs and valdefs emitted by the pattern matcher diff --git a/test/files/neg/t4425.check b/test/files/neg/t4425.check index 95b88a6b3d..00006c08f0 100644 --- a/test/files/neg/t4425.check +++ b/test/files/neg/t4425.check @@ -1,12 +1,12 @@ -t4425.scala:3: error: object X is not a case class constructor, nor does it have an unapply/unapplySeq method +t4425.scala:3: error: object X is not a case class, nor does it have an unapply/unapplySeq member Note: def unapply(x: Int)(y: Option[Int]): None.type exists in object X, but it cannot be used as an extractor due to its second non-implicit parameter list 42 match { case _ X _ => () } ^ -t4425.scala:8: error: object X is not a case class constructor, nor does it have an unapply/unapplySeq method +t4425.scala:8: error: object X is not a case class, nor does it have an unapply/unapplySeq member Note: def unapply(x: Int)(y: Int): Some[(Int, Int)] exists in object X, but it cannot be used as an extractor due to its second non-implicit parameter list 42 match { case _ X _ => () } ^ -t4425.scala:13: error: object X is not a case class constructor, nor does it have an unapply/unapplySeq method +t4425.scala:13: error: object X is not a case class, nor does it have an unapply/unapplySeq member Note: def unapply(x: String)(y: String): Some[(Int, Int)] exists in object X, but it cannot be used as an extractor due to its second non-implicit parameter list "" match { case _ X _ => () } ^ diff --git a/test/files/neg/t4425b.check b/test/files/neg/t4425b.check index 1186e8b609..8418b4fd12 100644 --- a/test/files/neg/t4425b.check +++ b/test/files/neg/t4425b.check @@ -1,61 +1,49 @@ -t4425b.scala:5: error: object X is not a case class constructor, nor does it have an unapply/unapplySeq method +t4425b.scala:5: error: object X is not a case class, nor does it have an unapply/unapplySeq member Note: def unapply(x: String)(y: String): Nothing exists in object X, but it cannot be used as an extractor due to its second non-implicit parameter list println( "" match { case _ X _ => "ok" ; case _ => "fail" }) ^ -t4425b.scala:6: error: object X is not a case class constructor, nor does it have an unapply/unapplySeq method +t4425b.scala:6: error: object X is not a case class, nor does it have an unapply/unapplySeq member Note: def unapply(x: String)(y: String): Nothing exists in object X, but it cannot be used as an extractor due to its second non-implicit parameter list println((X: Any) match { case _ X _ => "ok" ; case _ => "fail" }) ^ -t4425b.scala:7: error: object X is not a case class constructor, nor does it have an unapply/unapplySeq method +t4425b.scala:7: error: object X is not a case class, nor does it have an unapply/unapplySeq member Note: def unapply(x: String)(y: String): Nothing exists in object X, but it cannot be used as an extractor due to its second non-implicit parameter list println( "" match { case X(_) => "ok" ; case _ => "fail" }) ^ -t4425b.scala:8: error: object X is not a case class constructor, nor does it have an unapply/unapplySeq method +t4425b.scala:8: error: object X is not a case class, nor does it have an unapply/unapplySeq member Note: def unapply(x: String)(y: String): Nothing exists in object X, but it cannot be used as an extractor due to its second non-implicit parameter list println((X: Any) match { case X(_) => "ok" ; case _ => "fail" }) ^ -t4425b.scala:9: error: object X is not a case class constructor, nor does it have an unapply/unapplySeq method +t4425b.scala:9: error: object X is not a case class, nor does it have an unapply/unapplySeq member Note: def unapply(x: String)(y: String): Nothing exists in object X, but it cannot be used as an extractor due to its second non-implicit parameter list println( "" match { case X(_, _) => "ok" ; case _ => "fail" }) ^ -t4425b.scala:10: error: object X is not a case class constructor, nor does it have an unapply/unapplySeq method +t4425b.scala:10: error: object X is not a case class, nor does it have an unapply/unapplySeq member Note: def unapply(x: String)(y: String): Nothing exists in object X, but it cannot be used as an extractor due to its second non-implicit parameter list println((X: Any) match { case X(_, _) => "ok" ; case _ => "fail" }) ^ -t4425b.scala:18: error: wrong number of patterns for object X offering Nothing: expected 1, found 2 +t4425b.scala:18: error: too many patterns for object X: expected 1, found 2 println( "" match { case _ X _ => "ok" ; case _ => "fail" }) ^ -t4425b.scala:19: error: wrong number of patterns for object X offering Nothing: expected 1, found 2 +t4425b.scala:19: error: too many patterns for object X: expected 1, found 2 println((X: Any) match { case _ X _ => "ok" ; case _ => "fail" }) ^ -t4425b.scala:22: error: wrong number of patterns for object X offering Nothing: expected 1, found 2 +t4425b.scala:22: error: too many patterns for object X: expected 1, found 2 println( "" match { case X(_, _) => "ok" ; case _ => "fail" }) ^ -t4425b.scala:22: error: wrong number of patterns for object X offering Nothing: expected 1, found 2 - println( "" match { case X(_, _) => "ok" ; case _ => "fail" }) - ^ -t4425b.scala:23: error: wrong number of patterns for object X offering Nothing: expected 1, found 2 +t4425b.scala:23: error: too many patterns for object X: expected 1, found 2 println((X: Any) match { case X(_, _) => "ok" ; case _ => "fail" }) ^ -t4425b.scala:23: error: wrong number of patterns for object X offering Nothing: expected 1, found 2 - println((X: Any) match { case X(_, _) => "ok" ; case _ => "fail" }) - ^ -t4425b.scala:31: error: wrong number of patterns for object X offering Nothing: expected 1, found 2 +t4425b.scala:31: error: too many patterns for object X offering Nothing: expected 1, found 2 println( "" match { case _ X _ => "ok" ; case _ => "fail" }) ^ -t4425b.scala:32: error: wrong number of patterns for object X offering Nothing: expected 1, found 2 +t4425b.scala:32: error: too many patterns for object X offering Nothing: expected 1, found 2 println((X: Any) match { case _ X _ => "ok" ; case _ => "fail" }) ^ -t4425b.scala:35: error: wrong number of patterns for object X offering Nothing: expected 1, found 2 +t4425b.scala:35: error: too many patterns for object X offering Nothing: expected 1, found 2 println( "" match { case X(_, _) => "ok" ; case _ => "fail" }) ^ -t4425b.scala:35: error: wrong number of patterns for object X offering Nothing: expected 1, found 2 - println( "" match { case X(_, _) => "ok" ; case _ => "fail" }) - ^ -t4425b.scala:36: error: wrong number of patterns for object X offering Nothing: expected 1, found 2 +t4425b.scala:36: error: too many patterns for object X offering Nothing: expected 1, found 2 println((X: Any) match { case X(_, _) => "ok" ; case _ => "fail" }) ^ -t4425b.scala:36: error: wrong number of patterns for object X offering Nothing: expected 1, found 2 - println((X: Any) match { case X(_, _) => "ok" ; case _ => "fail" }) - ^ -18 errors found +14 errors found diff --git a/test/files/neg/t5903a.check b/test/files/neg/t5903a.check index 2e5cc87167..34003b0a82 100644 --- a/test/files/neg/t5903a.check +++ b/test/files/neg/t5903a.check @@ -1,4 +1,4 @@ -Test_2.scala:4: error: wrong number of patterns for <$anon: AnyRef> offering (SomeTree.type, SomeTree.type): expected 2, found 3 +Test_2.scala:4: error: too many patterns for <$anon: AnyRef> offering (SomeTree.type, SomeTree.type): expected 2, found 3 case nq"$x + $y + $z" => println((x, y)) ^ one error found diff --git a/test/files/neg/t6675b.check b/test/files/neg/t6675b.check new file mode 100644 index 0000000000..77f6b3ccbc --- /dev/null +++ b/test/files/neg/t6675b.check @@ -0,0 +1,37 @@ +t6675b.scala:17: warning: object LeftOrRight expects 2 patterns to hold (Int, Int) but crushing into 2-tuple to fit single pattern (SI-6675) + def f1 = (Left((0, 0)): Either[(Int, Int), (Int, Int)]) match { case LeftOrRight(a) => a } // warn + ^ +t6675b.scala:19: error: constructor cannot be instantiated to expected type; + found : (T1, T2, T3) + required: (Int, Int) + def f3 = (Left((0, 0)): Either[(Int, Int), (Int, Int)]) match { case LeftOrRight((a, b, c)) => a } // fail + ^ +t6675b.scala:24: warning: object LeftOrRight expects 2 patterns to hold (A, A) but crushing into 2-tuple to fit single pattern (SI-6675) + def f2[A](x: A) = (Left(x -> x): Either[(A, A), (A, A)]) match { case LeftOrRight(a) => a } // warn + ^ +t6675b.scala:26: error: constructor cannot be instantiated to expected type; + found : (T1, T2, T3) + required: (?A11, ?A12) where type ?A12 <: A (this is a GADT skolem), type ?A11 <: A (this is a GADT skolem) + def f4[A](x: A) = (Left(x -> x): Either[(A, A), (A, A)]) match { case LeftOrRight((a, b, c)) => a } // fail + ^ +t6675b.scala:30: warning: object NativelyTwo expects 2 patterns to hold ((Int, Int), (Int, Int)) but crushing into 2-tuple to fit single pattern (SI-6675) + def f1 = (Left((0, 0)): Either[(Int, Int), (Int, Int)]) match { case NativelyTwo(a) => a } // warn + ^ +t6675b.scala:32: error: constructor cannot be instantiated to expected type; + found : (T1, T2, T3) + required: ((Int, Int), (Int, Int)) + def f3 = (Left((0, 0)): Either[(Int, Int), (Int, Int)]) match { case NativelyTwo((a, b, c)) => a } // fail + ^ +t6675b.scala:36: warning: object NativelyTwo expects 2 patterns to hold (A, A) but crushing into 2-tuple to fit single pattern (SI-6675) + def f1[A](x: A) = (Left(x): Either[A, A]) match { case NativelyTwo(a) => a } // warn + ^ +t6675b.scala:37: warning: object NativelyTwo expects 2 patterns to hold ((A, A), (A, A)) but crushing into 2-tuple to fit single pattern (SI-6675) + def f2[A](x: A) = (Left(x -> x): Either[(A, A), (A, A)]) match { case NativelyTwo(a) => a } // warn + ^ +t6675b.scala:39: error: constructor cannot be instantiated to expected type; + found : (T1, T2, T3) + required: ((?A17, ?A18), (?A19, ?A20)) where type ?A20 <: A (this is a GADT skolem), type ?A19 <: A (this is a GADT skolem), type ?A18 <: A (this is a GADT skolem), type ?A17 <: A (this is a GADT skolem) + def f4[A](x: A) = (Left(x -> x): Either[(A, A), (A, A)]) match { case NativelyTwo((a, b, c)) => a } // fail + ^ +5 warnings found +four errors found diff --git a/test/files/neg/t6675b.flags b/test/files/neg/t6675b.flags new file mode 100644 index 0000000000..1008b0a70c --- /dev/null +++ b/test/files/neg/t6675b.flags @@ -0,0 +1 @@ +-Xlint diff --git a/test/files/neg/t6675b.scala b/test/files/neg/t6675b.scala new file mode 100644 index 0000000000..c86c9c3955 --- /dev/null +++ b/test/files/neg/t6675b.scala @@ -0,0 +1,40 @@ +object LeftOrRight { + def unapply[A](value: Either[A, A]): Option[A] = value match { + case scala.Left(x) => Some(x) + case scala.Right(x) => Some(x) + } +} + +object NativelyTwo { + def unapply[A](value: Either[A, A]): Option[(A, A)] = value match { + case scala.Left(x) => Some(x -> x) + case scala.Right(x) => Some(x -> x) + } +} + + +class A { + def f1 = (Left((0, 0)): Either[(Int, Int), (Int, Int)]) match { case LeftOrRight(a) => a } // warn + def f2 = (Left((0, 0)): Either[(Int, Int), (Int, Int)]) match { case LeftOrRight((a, b)) => a } // no warn + def f3 = (Left((0, 0)): Either[(Int, Int), (Int, Int)]) match { case LeftOrRight((a, b, c)) => a } // fail +} + +class B { + def f1[A](x: A) = (Left(x): Either[A, A]) match { case LeftOrRight(a) => a } // no warn + def f2[A](x: A) = (Left(x -> x): Either[(A, A), (A, A)]) match { case LeftOrRight(a) => a } // warn + def f3[A](x: A) = (Left(x -> x): Either[(A, A), (A, A)]) match { case LeftOrRight((a, b)) => a } // no warn + def f4[A](x: A) = (Left(x -> x): Either[(A, A), (A, A)]) match { case LeftOrRight((a, b, c)) => a } // fail +} + +class C { + def f1 = (Left((0, 0)): Either[(Int, Int), (Int, Int)]) match { case NativelyTwo(a) => a } // warn + def f2 = (Left((0, 0)): Either[(Int, Int), (Int, Int)]) match { case NativelyTwo((a, b)) => a } // no warn + def f3 = (Left((0, 0)): Either[(Int, Int), (Int, Int)]) match { case NativelyTwo((a, b, c)) => a } // fail +} + +class D { + def f1[A](x: A) = (Left(x): Either[A, A]) match { case NativelyTwo(a) => a } // warn + def f2[A](x: A) = (Left(x -> x): Either[(A, A), (A, A)]) match { case NativelyTwo(a) => a } // warn + def f3[A](x: A) = (Left(x -> x): Either[(A, A), (A, A)]) match { case NativelyTwo((a, b)) => a } // no warn + def f4[A](x: A) = (Left(x -> x): Either[(A, A), (A, A)]) match { case NativelyTwo((a, b, c)) => a } // fail +} diff --git a/test/files/neg/t7214neg.check b/test/files/neg/t7214neg.check index 0660cccd02..291af04578 100644 --- a/test/files/neg/t7214neg.check +++ b/test/files/neg/t7214neg.check @@ -1,7 +1,4 @@ -t7214neg.scala:28: error: wrong number of patterns for object Extractor offering Any: expected 1, found 0 +t7214neg.scala:28: error: not enough patterns for object Extractor offering Any: expected 1, found 0 case Extractor() => ^ -t7214neg.scala:28: error: wrong number of patterns for object Extractor offering Any: expected 1, found 0 - case Extractor() => - ^ -two errors found +one error found diff --git a/test/files/neg/t7850.check b/test/files/neg/t7850.check new file mode 100644 index 0000000000..317be2bbce --- /dev/null +++ b/test/files/neg/t7850.check @@ -0,0 +1,7 @@ +t7850.scala:11: error: an unapply result must have a member `def isEmpty: Boolean (found: def isEmpty: Casey) + val Casey(x1) = new Casey(1) + ^ +t7850.scala:12: error: an unapply result must have a member `def isEmpty: Boolean + val Dingy(x2) = new Dingy(1) + ^ +two errors found diff --git a/test/files/neg/t7850.scala b/test/files/neg/t7850.scala new file mode 100644 index 0000000000..04edad82b5 --- /dev/null +++ b/test/files/neg/t7850.scala @@ -0,0 +1,16 @@ +// isEmpty returns non-boolean +class Casey(a: Int) { def isEmpty = this; def get = this } +object Casey { def unapply(a: Casey) = a } + +// no isEmpty method at all +class Dingy(a: Int) { def get = this } +object Dingy { def unapply(a: Dingy) = a } + +object Test { + def main(args: Array[String]) { + val Casey(x1) = new Casey(1) + val Dingy(x2) = new Dingy(1) + println(s"$x1 $x2") + } +} + diff --git a/test/files/neg/t7897.check b/test/files/neg/t7897.check new file mode 100644 index 0000000000..48eff511c7 --- /dev/null +++ b/test/files/neg/t7897.check @@ -0,0 +1,4 @@ +t7897.scala:19: error: value length is not a member of p0.Single + case p0.Single(x) => println(s"`$x` has ${x.length} chars") + ^ +one error found diff --git a/test/files/neg/t7897.scala b/test/files/neg/t7897.scala new file mode 100644 index 0000000000..87c966b1e0 --- /dev/null +++ b/test/files/neg/t7897.scala @@ -0,0 +1,23 @@ +package p0 { + class Single(val x: Any) extends AnyRef with Product1[String] { + private def s = "" + x + override def canEqual(x: Any) = this eq x.asInstanceOf[AnyRef] + def isEmpty = false + def get = this + def _1 = s + " only" + + override def toString = s"Single(${_1})" + } + + object Single { + def unapply(x: Any): Single = new Single(x) + } +} +object Test { + def main(args: Array[String]): Unit = { + "catdog" match { + case p0.Single(x) => println(s"`$x` has ${x.length} chars") + case x => println("fail: " + x) + } + } +} diff --git a/test/files/neg/t997.check b/test/files/neg/t997.check index 8c41060ba2..b118792229 100644 --- a/test/files/neg/t997.check +++ b/test/files/neg/t997.check @@ -1,7 +1,4 @@ -t997.scala:13: error: wrong number of patterns for object Foo offering (String, String): expected 2, found 3 +t997.scala:13: error: too many patterns for object Foo offering (String, String): expected 2, found 3 "x" match { case Foo(a, b, c) => Console.println((a,b,c)) } ^ -t997.scala:13: error: wrong number of patterns for object Foo offering (String, String): expected 2, found 3 -"x" match { case Foo(a, b, c) => Console.println((a,b,c)) } - ^ -two errors found +one error found diff --git a/test/files/pos/t8045.scala b/test/files/pos/t8045.scala new file mode 100644 index 0000000000..21154e386a --- /dev/null +++ b/test/files/pos/t8045.scala @@ -0,0 +1,17 @@ +object Test extends App { + case class Number(i: Int) + + object UnliftNumber { + def unapply(t: Any): Option[Number] = t match { + case i: Int => Some(Number(i)) + case _ => None + } + } + + def eval(expr: Any): Option[Number] = expr match { + case UnliftNumber(n) => Some(n) + case _ => None + } + + println(eval(1)) +} diff --git a/test/files/pos/t8128.scala b/test/files/pos/t8128.scala new file mode 100644 index 0000000000..b6f76691b0 --- /dev/null +++ b/test/files/pos/t8128.scala @@ -0,0 +1,15 @@ +object G { + def unapply(m: Any): Option[_] = Some("") +} + +object H { + def unapplySeq(m: Any): Option[Seq[_]] = None +} + +object Test { + (0: Any) match { + case G(v) => v + case H(v) => v + case _ => + } +} diff --git a/test/files/run/name-based-patmat.check b/test/files/run/name-based-patmat.check index 1cc605ea3d..3d5fc40ed7 100644 --- a/test/files/run/name-based-patmat.check +++ b/test/files/run/name-based-patmat.check @@ -1,3 +1,5 @@ +`catdog only` has 11 chars +`catdog only, no product` has 23 chars catdog 2 catdogs! A ha ha! 3 catdogs! A ha ha! diff --git a/test/files/run/name-based-patmat.scala b/test/files/run/name-based-patmat.scala index 2c429c141f..8e20940100 100644 --- a/test/files/run/name-based-patmat.scala +++ b/test/files/run/name-based-patmat.scala @@ -1,5 +1,33 @@ final class MiniSome[T](val get: T) extends AnyVal { def isEmpty = false } +package p0 { + class Single(val x: Any) extends AnyRef with Product1[String] { + private def s = "" + x + override def canEqual(x: Any) = this eq x.asInstanceOf[AnyRef] + def isEmpty = false + def get = this + def _1 = s + " only" + + override def toString = s"Single(${_1})" + } + + object Single { + def unapply(x: Any): Single = new Single(x) + } + + class SingleNoProduct(val x: Any) extends AnyRef { + private def s = "" + x + def isEmpty = false + def get = s + " only, no product" + + override def toString = s"SingleNoProduct($get)" + } + + object SingleNoProduct { + def unapply(x: Any): SingleNoProduct = new SingleNoProduct(x) + } +} + package p1 { class Triple(val x: Any) extends AnyRef with Product3[String, String, String] { private def s = "" + x @@ -49,14 +77,16 @@ package p3 { } object Test { - - // def f(x: Any) = x match { - // case p1.Foo(x, y, z) => println((x, y, z)) - // case x => println(x) - // } - def main(args: Array[String]): Unit = { "catdog" match { + case p0.Single(x) => println(s"`${x._1}` has ${x._1.length} chars") + case x => println("fail: " + x) + } + "catdog" match { + case p0.SingleNoProduct(x) => println(s"`$x` has ${x.length} chars") + case x => println("fail: " + x) + } + "catdog" match { case p1.Triple(x, y, z) => List(x, y, z) foreach println case x => println("fail: " + x) } diff --git a/test/files/run/patmat-mix-case-extractor.check b/test/files/run/patmat-mix-case-extractor.check new file mode 100644 index 0000000000..a6e1bd23df --- /dev/null +++ b/test/files/run/patmat-mix-case-extractor.check @@ -0,0 +1,8 @@ +-1 +6 +4 +18 +-1 +1006 +1004 +1018 diff --git a/test/files/run/patmat-mix-case-extractor.scala b/test/files/run/patmat-mix-case-extractor.scala new file mode 100644 index 0000000000..964e6f743c --- /dev/null +++ b/test/files/run/patmat-mix-case-extractor.scala @@ -0,0 +1,110 @@ +trait CaseClass +trait ProdCaseClass extends CaseClass { def x: Int } +trait SeqCaseClass extends CaseClass { def xs: Seq[Int] } + +case class CaseClass1() extends CaseClass +case class CaseClass2(xs: Int*) extends SeqCaseClass +case class CaseClass3(x: Int) extends ProdCaseClass +case class CaseClass4(x: Int, xs: Int*) extends ProdCaseClass with SeqCaseClass + +object Extractor1 { def unapply(x: CaseClass): Boolean = false } +object Extractor2 { def unapplySeq(x: SeqCaseClass): Option[Seq[Int]] = Some(x.xs) } +object Extractor3 { def unapply(x: ProdCaseClass): Option[Int] = Some(x.x) } +object Extractor4 { def unapplySeq(x: ProdCaseClass with SeqCaseClass): Option[(Int, Seq[Int])] = Some(x.x, x.xs) } + +class A { + def f1(x: Any) = x match { + case CaseClass1() => -1 + case CaseClass2(xs @ _*) => xs.sum + case CaseClass3(x) => x + case CaseClass4(x, xs @ _*) => x + xs.sum + case Extractor4(x, xs @ _*) => 1000 + x + xs.sum + case Extractor3(x) => 1000 + x + case Extractor2(xs @ _*) => 1000 + xs.sum + case Extractor1() => -3 + case _ => -2 + } + def f2(x: Any) = x match { + case Extractor4(x, xs @ _*) => 1000 + x + xs.sum + case Extractor3(x) => 1000 + x + case Extractor2(xs @ _*) => 1000 + xs.sum + case Extractor1() => -3 + case CaseClass1() => -1 + case CaseClass2(xs @ _*) => xs.sum + case CaseClass3(x) => x + case CaseClass4(x, xs @ _*) => x + xs.sum + case _ => -2 + } + def run() { + List( + f1(CaseClass1()), + f1(CaseClass2(1, 2, 3)), + f1(CaseClass3(4)), + f1(CaseClass4(5, 6, 7)), + f2(CaseClass1()), + f2(CaseClass2(1, 2, 3)), + f2(CaseClass3(4)), + f2(CaseClass4(5, 6, 7)) + ) foreach println + } +} + +object Test { + def main(args: Array[String]): Unit = { + (new A).run + } +} + + +class B { + case class CaseClass0() + case class CaseClass0v(xs: Int*) + + case class CaseClass(x: Int, y: Int) + object Extractor { def unapply(x: Any): Option[(Int, Int)] = Some((1, 1)) } + + case class CaseSeq(x: Char, y: Double, zs: Int*) + object ExtractorSeq { def unapplySeq(x: Any): Option[(Int, Int, Seq[Int])] = Some((1, 1, List(1))) } + + def f1(x: CaseClass) = x match { case CaseClass(y, z) => y } + def f2(x: Any) = x match { case Extractor(y, z) => y } + + def f3(x: CaseSeq) = x match { + case CaseSeq(x, y) => y + case CaseSeq(x, y, z) => z + } + def f4(x: CaseSeq) = x match { + case CaseSeq(x, y, z) => z :: Nil + case CaseSeq(x, y, z @ _*) => z + } + + def f5(x: Any) = x match { case ExtractorSeq(x, y, z) => z } + def f6(x: Any) = x match { case ExtractorSeq(x, y, z @ _*) => z } + + def g1(x: CaseClass0) = x match { + case CaseClass0() => true + } + def g2(x: CaseClass0v) = x match { + case CaseClass0v() => true + case CaseClass0v(5) => true + case CaseClass0v(x) => true + case CaseClass0v(xs @ _*) => false + } +} + +package p1 { + trait _X { + case class _Foo(); + object _Bar { + def unapply(foo: _Foo): Boolean = true; + } + } + + object Y extends _X { + val foo = _Foo() + foo match { + case _Bar() => + case _ => assert(false) + } + } +} diff --git a/test/pending/pos/t8128b.scala b/test/pending/pos/t8128b.scala new file mode 100644 index 0000000000..dd44a25a90 --- /dev/null +++ b/test/pending/pos/t8128b.scala @@ -0,0 +1,18 @@ +class Optiony[X] { def isEmpty = true; def get: X = ??? } +class Seqy[X] { def head: X = ???; def length = 0; def apply(i: Int): X = ??? } + +object G { + def unapply(m: Any): Optiony[_] = ??? +} + +object H { + def unapplySeq(m: Any): Optiony[Seqy[_]] = ??? +} + +object Test { + (0: Any) match { + case G(v) => v + case H(v) => v + case _ => + } +} |