diff options
Diffstat (limited to 'src/compiler/scala/tools/nsc/transform/AddInterfaces.scala')
-rw-r--r-- | src/compiler/scala/tools/nsc/transform/AddInterfaces.scala | 310 |
1 files changed, 19 insertions, 291 deletions
diff --git a/src/compiler/scala/tools/nsc/transform/AddInterfaces.scala b/src/compiler/scala/tools/nsc/transform/AddInterfaces.scala index 82e7c76409..9a8eca152f 100644 --- a/src/compiler/scala/tools/nsc/transform/AddInterfaces.scala +++ b/src/compiler/scala/tools/nsc/transform/AddInterfaces.scala @@ -8,208 +8,17 @@ package transform import symtab._ import Flags._ -import scala.tools.nsc.util.ClassPath abstract class AddInterfaces extends InfoTransform { self: Erasure => import global._ // the global environment import definitions._ // standard classes and methods - /** The phase sets lateINTERFACE for non-interface traits that now - * become interfaces. It sets lateDEFERRED for formerly concrete - * methods in such traits. + /** lateDEFERRED for formerly concrete methods in such traits. */ - override def phaseNewFlags: Long = lateDEFERRED | lateINTERFACE - - /** A lazily constructed map that associates every non-interface trait with - * its implementation class. - */ - private val implClassMap = perRunCaches.newMap[Symbol, Symbol]() - - /** A lazily constructed map that associates every concrete method in a non-interface - * trait that's currently compiled with its corresponding method in the trait's - * implementation class. - */ - private val implMethodMap = perRunCaches.newMap[Symbol, Symbol]() - - override def newPhase(prev: scala.tools.nsc.Phase): StdPhase = { - implClassMap.clear() - implMethodMap.clear() - super.newPhase(prev) - } - - /** Is given trait member symbol a member of the trait's interface - * after this transform is performed? - */ - private def isInterfaceMember(sym: Symbol) = ( - sym.isType || { - sym.info // initialize to set lateMETHOD flag if necessary - - ( sym.isMethod - && !sym.isLabel - && !sym.isPrivate - && (!(sym hasFlag BRIDGE) || sym.hasBridgeAnnotation) // count @bridge annotated classes as interface members - && !sym.isConstructor - && !sym.isImplOnly - ) - } - ) - - /** Does symbol need an implementation method? */ - def needsImplMethod(sym: Symbol) = ( - sym.isMethod - && isInterfaceMember(sym) - && (!sym.hasFlag(DEFERRED | SUPERACCESSOR) || (sym hasFlag lateDEFERRED)) - ) - - def implClassPhase = currentRun.erasurePhase.next - - private def newImplClass(iface: Symbol): Symbol = { - val inClass = iface.owner.isClass - val implName = tpnme.implClassName(iface.name) - val implFlags = (iface.flags & ~(INTERFACE | lateINTERFACE)) | IMPLCLASS - - val impl0 = { - if (!inClass) NoSymbol - else { - val typeInfo = iface.owner.info - typeInfo.decl(implName) match { - case NoSymbol => NoSymbol - case implSym => - // Unlink a pre-existing symbol only if the implementation class is - // visible on the compilation classpath. In general this is true under - // -optimise and not otherwise, but the classpath can use arbitrary - // logic so the classpath must be queried. - // TODO this is not taken into account by flat classpath yet - classPath match { - case cp: ClassPath[_] if !cp.context.isValidName(implName + ".class") => - log(s"not unlinking $iface's existing implClass ${implSym.name} because it is not on the classpath.") - implSym - case _ => - typeInfo.decls unlink implSym - NoSymbol - } - } - } - } - - val impl = impl0 orElse { - val impl = iface.owner.newImplClass(implName, iface.pos, implFlags) - if (iface.thisSym != iface) { - impl.typeOfThis = iface.typeOfThis - impl.thisSym setName iface.thisSym.name - } - impl.associatedFile = iface.sourceFile - if (inClass) - iface.owner.info.decls enter impl - - impl - } - if (currentRun compiles iface) - currentRun.symSource(impl) = iface.sourceFile - - implClassMap(iface) = impl - impl setInfo new LazyImplClassType(iface) - } - - /** Return the implementation class of a trait; create a new one if one does not yet exist */ - def implClass(iface: Symbol): Symbol = { - iface.info - - implClassMap.getOrElse(iface, enteringPhase(implClassPhase) { - if (iface.implClass eq NoSymbol) - debuglog(s"${iface.fullLocationString} has no implClass yet, creating it now.") - else - log(s"${iface.fullLocationString} impl class is ${iface.implClass.nameString}") - - newImplClass(iface) - }) - } - - /** A lazy type to set the info of an implementation class - * The parents of an implementation class for trait iface are: - * - * - superclass: Object - * - mixin classes: mixin classes of iface where every non-interface - * trait is mapped to its implementation class, followed by iface itself. - * - * The declarations of a mixin class are: - * - for every interface member of iface: its implementation method, if one is needed - * - every former member of iface that is implementation only - */ - private class LazyImplClassType(iface: Symbol) extends LazyType with FlagAgnosticCompleter { - /** Compute the decls of implementation class implClass, - * given the decls ifaceDecls of its interface. - */ - private def implDecls(implClass: Symbol, ifaceDecls: Scope): Scope = { - debuglog("LazyImplClassType calculating decls for " + implClass) - - val decls = newScope - if ((ifaceDecls lookup nme.MIXIN_CONSTRUCTOR) == NoSymbol) { - log("Adding mixin constructor to " + implClass) - - decls enter ( - implClass.newMethod(nme.MIXIN_CONSTRUCTOR, implClass.pos) - setInfo MethodType(Nil, UnitTpe) - ) - } - - for (sym <- ifaceDecls) { - if (isInterfaceMember(sym)) { - if (needsImplMethod(sym)) { - val clone = sym.cloneSymbol(implClass).resetFlag(lateDEFERRED) - if (currentRun.compiles(implClass)) implMethodMap(sym) = clone - decls enter clone - sym setFlag lateDEFERRED - if (!sym.isSpecialized) - log(s"Cloned ${sym.name} from ${sym.owner} into implClass ${implClass.fullName}") - } - } - else { - log(s"Destructively modifying owner of $sym from ${sym.owner} to $implClass") - sym.owner = implClass - // note: OK to destructively modify the owner here, - // because symbol will not be accessible from outside the sourcefile. - // mixin constructors are corrected separately; see TermSymbol.owner - decls enter sym - } - } - - decls - } - - override def complete(implSym: Symbol) { - debuglog("LazyImplClassType completing " + implSym) - - /* If `tp` refers to a non-interface trait, return a - * reference to its implementation class. Otherwise return `tp`. - */ - def mixinToImplClass(tp: Type): Type = AddInterfaces.this.erasure(implSym) { - tp match { //@MATN: no normalize needed (comes after erasure) - case TypeRef(pre, sym, _) if sym.needsImplClass => - typeRef(pre, implClass(sym), Nil) - case _ => - tp - } - } - def implType(tp: Type): Type = tp match { - case ClassInfoType(parents, decls, _) => - assert(phase == implClassPhase, tp) - // Impl class parents: Object first, matching interface last. - val implParents = ObjectTpe +: (parents.tail map mixinToImplClass filter (_.typeSymbol != ObjectClass)) :+ iface.tpe - ClassInfoType(implParents, implDecls(implSym, decls), implSym) - case PolyType(_, restpe) => - implType(restpe) - } - implSym setInfo implType(enteringErasure(iface.info)) - } - - override def load(clazz: Symbol) { complete(clazz) } - } + override def phaseNewFlags: Long = lateDEFERRED def transformMixinInfo(tp: Type): Type = tp match { case ClassInfoType(parents, decls, clazz) if clazz.isPackageClass || !clazz.isJavaDefined => - if (clazz.needsImplClass) - implClass(clazz setFlag lateINTERFACE) // generate an impl class val parents1 = parents match { case Nil => Nil @@ -218,21 +27,20 @@ abstract class AddInterfaces extends InfoTransform { self: Erasure => if (clazz.isTrait) ObjectTpe :: tl else parents } - val decls1 = scopeTransform(clazz)( - decls filter (sym => - if (clazz.isInterface) isInterfaceMember(sym) - else sym.isClass || sym.isTerm - ) - ) - ClassInfoType(parents1, decls1, clazz) + if (clazz.isTrait) { + decls foreach { sym => + if (!sym.isType) sym.info // initialize to set lateMETHOD flag if necessary + } + } + if (parents1 eq parents) tp + else ClassInfoType(parents1, decls, clazz) case _ => tp } // Tree transformation -------------------------------------------------------------- - private class ChangeOwnerAndReturnTraverser(oldowner: Symbol, newowner: Symbol) - extends ChangeOwnerTraverser(oldowner, newowner) { + extends ChangeOwnerTraverser(oldowner, newowner) { override def traverse(tree: Tree) { tree match { case _: Return => change(tree.symbol) @@ -242,63 +50,10 @@ abstract class AddInterfaces extends InfoTransform { self: Erasure => } } - private def createMemberDef(tree: Tree, isForInterface: Boolean)(create: Tree => Tree) = { - val isInterfaceTree = tree.isDef && isInterfaceMember(tree.symbol) - if (isInterfaceTree && needsImplMethod(tree.symbol)) - create(tree) - else if (isInterfaceTree == isForInterface) - tree - else - EmptyTree - } - private def implMemberDef(tree: Tree): Tree = createMemberDef(tree, false)(implMethodDef) - private def ifaceMemberDef(tree: Tree): Tree = createMemberDef(tree, true)(t => DefDef(t.symbol, EmptyTree)) - - private def ifaceTemplate(templ: Template): Template = - treeCopy.Template(templ, templ.parents, noSelfType, templ.body map ifaceMemberDef) - - /** Transforms the member tree containing the implementation - * into a member of the impl class. - */ - private def implMethodDef(tree: Tree): Tree = { - val impl = implMethodMap.getOrElse(tree.symbol, abort("implMethod missing for " + tree.symbol)) - - val newTree = if (impl.isErroneous) tree else { // e.g. res/t687 - // SI-5167: Ensure that the tree that we are grafting refers the parameter symbols from the - // new method symbol `impl`, rather than the symbols of the original method signature in - // the trait. `tree setSymbol impl` does *not* suffice! - val DefDef(_, _, _, vparamss, _, _) = tree - val oldSyms = vparamss.flatten.map(_.symbol) - val newSyms = impl.info.paramss.flatten - assert(oldSyms.length == newSyms.length, (oldSyms, impl, impl.info)) - tree.substituteSymbols(oldSyms, newSyms) - } - new ChangeOwnerAndReturnTraverser(newTree.symbol, impl)(newTree setSymbol impl) - } - - /** Add mixin constructor definition - * def $init$(): Unit = () - * to `stats` unless there is already one. - */ - private def addMixinConstructorDef(clazz: Symbol, stats: List[Tree]): List[Tree] = - if (treeInfo.firstConstructor(stats) != EmptyTree) stats - else DefDef(clazz.primaryConstructor, Block(List(), Literal(Constant(())))) :: stats - - private def implTemplate(clazz: Symbol, templ: Template): Template = atPos(templ.pos) { - val templ1 = ( - Template(templ.parents, noSelfType, addMixinConstructorDef(clazz, templ.body map implMemberDef)) - setSymbol clazz.newLocalDummy(templ.pos) - ) - templ1.changeOwner(templ.symbol.owner -> clazz, templ.symbol -> templ1.symbol) - templ1 - } - - def implClassDefs(trees: List[Tree]): List[Tree] = { - trees collect { - case cd: ClassDef if cd.symbol.needsImplClass => - val clazz = implClass(cd.symbol).initialize - ClassDef(clazz, implTemplate(clazz, cd.impl)) - } + private def mkAssign(clazz: Symbol, assignSym: Symbol, rhs: Tree): Tree = { + val qual = Select(This(clazz), assignSym) + if (assignSym.isSetter) Apply(qual, List(rhs)) + else Assign(qual, rhs) } /** Add calls to supermixin constructors @@ -306,15 +61,16 @@ abstract class AddInterfaces extends InfoTransform { self: Erasure => * to tree, which is assumed to be the body of a constructor of class clazz. */ private def addMixinConstructorCalls(tree: Tree, clazz: Symbol): Tree = { - def mixinConstructorCall(impl: Symbol): Tree = atPos(tree.pos) { - Apply(Select(This(clazz), impl.primaryConstructor), List()) + def mixinConstructorCall(mc: Symbol): Tree = atPos(tree.pos) { + Apply(SuperSelect(clazz, mc.primaryConstructor), Nil) } val mixinConstructorCalls: List[Tree] = { for (mc <- clazz.mixinClasses.reverse - if mc.hasFlag(lateINTERFACE)) - yield mixinConstructorCall(implClass(mc)) + if mc.isTrait && mc.primaryConstructor != NoSymbol) + yield mixinConstructorCall(mc) } tree match { + case Block(Nil, expr) => // AnyVal constructor - have to provide a real body so the // jvm doesn't throw a VerifyError. But we can't add the @@ -331,42 +87,14 @@ abstract class AddInterfaces extends InfoTransform { self: Erasure => } protected val mixinTransformer = new Transformer { - override def transformStats(stats: List[Tree], exprOwner: Symbol): List[Tree] = - (super.transformStats(stats, exprOwner) ::: - super.transformStats(implClassDefs(stats), exprOwner)) override def transform(tree: Tree): Tree = { val sym = tree.symbol val tree1 = tree match { - case ClassDef(mods, _, _, impl) if sym.needsImplClass => - implClass(sym).initialize // to force lateDEFERRED flags - copyClassDef(tree)(mods = mods | INTERFACE, impl = ifaceTemplate(impl)) case DefDef(_,_,_,_,_,_) if sym.isClassConstructor && sym.isPrimaryConstructor && sym.owner != ArrayClass => deriveDefDef(tree)(addMixinConstructorCalls(_, sym.owner)) // (3) case Template(parents, self, body) => val parents1 = sym.owner.info.parents map (t => TypeTree(t) setPos tree.pos) treeCopy.Template(tree, parents1, noSelfType, body) - case This(_) if sym.needsImplClass => - val impl = implClass(sym) - var owner = currentOwner - while (owner != sym && owner != impl) owner = owner.owner; - if (owner == impl) This(impl) setPos tree.pos - else tree - //TODO what about this commented out code? -/* !!! - case Super(qual, mix) => - val mix1 = mix - if (mix == tpnme.EMPTY) mix - else { - val ps = enteringErasure { - sym.info.parents dropWhile (p => p.symbol.name != mix) - } - assert(!ps.isEmpty, tree); - if (ps.head.symbol.needsImplClass) implClass(ps.head.symbol).name - else mix - } - if (sym.needsImplClass) Super(implClass(sym), mix1) setPos tree.pos - else treeCopy.Super(tree, qual, mix1) -*/ case _ => tree } |