Analyzer Plugins

AnnotationCheckers are insufficient because they live outside the
compiler cake and it's not possible to pass a Typer into an annotation
checker.

Analyzer plugins hook into important places of the compiler:

  - when the namer assigns a type to a symbol (plus a special hook for
    accessors)
  - before typing a tree, to modify the expected type
  - after typing a tree, to modify the type assigned to the tree

Analyzer plugins and annotation checker can be activated only during
selected phases of the compiler.

Refactored the CPS plugin to use an analyzer plugin (since
adaptToAnnotations is now part of analyzer plugins, no longer
annotation checkers).

1 files changed, 17 insertions, 11 deletions

diff --git a/src/compiler/scala/tools/nsc/typechecker/Namers.scala b/src/compiler/scala/tools/nsc/typechecker/Namers.scala
index 833a606565..c728185d4e 100644
--- a/src/compiler/scala/tools/nsc/typechecker/Namers.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/Namers.scala
@@ -755,10 +755,9 @@ trait Namers extends MethodSynthesis {
     def accessorTypeCompleter(tree: ValDef, isSetter: Boolean) = mkTypeCompleter(tree) { sym =>
       logAndValidate(sym) {
         sym setInfo {
-          if (isSetter)
-            MethodType(List(sym.newSyntheticValueParam(typeSig(tree))), UnitClass.tpe)
-          else
-            NullaryMethodType(typeSig(tree))
+          val tp = if (isSetter) MethodType(List(sym.newSyntheticValueParam(typeSig(tree))), UnitClass.tpe)
+                   else NullaryMethodType(typeSig(tree))
+          pluginsTypeSigAccessor(tp, typer, tree, sym)
         }
       }
     }
@@ -903,7 +902,8 @@ trait Namers extends MethodSynthesis {
       for (cda <- module.attachments.get[ConstructorDefaultsAttachment]) {
         cda.companionModuleClassNamer = templateNamer
       }
-      ClassInfoType(parents, decls, clazz)
+      val classTp = ClassInfoType(parents, decls, clazz)
+      pluginsTypeSig(classTp, templateNamer.typer, templ, WildcardType)
     }
 
     private def classSig(cdef: ClassDef): Type = {
@@ -913,17 +913,18 @@ trait Namers extends MethodSynthesis {
       val resultType = templateSig(impl)
 
       val res = GenPolyType(tparams0, resultType)
+      val pluginsTp = pluginsTypeSig(res, typer, cdef, WildcardType)
 
       // Already assign the type to the class symbol (monoTypeCompleter will do it again).
       // Allows isDerivedValueClass to look at the info.
-      clazz setInfo res
+      clazz setInfo pluginsTp
       if (clazz.isDerivedValueClass) {
         log("Ensuring companion for derived value class " + cdef.name + " at " + cdef.pos.show)
         clazz setFlag FINAL
         // Don't force the owner's info lest we create cycles as in SI-6357.
         enclosingNamerWithScope(clazz.owner.rawInfo.decls).ensureCompanionObject(cdef)
       }
-      res
+      pluginsTp
     }
 
     private def moduleSig(mdef: ModuleDef): Type = {
@@ -931,9 +932,10 @@ trait Namers extends MethodSynthesis {
       // The info of both the module and the moduleClass symbols need to be assigned. monoTypeCompleter assigns
       // the result of typeSig to the module symbol. The module class info is assigned here as a side-effect.
       val result = templateSig(mdef.impl)
+      val pluginsTp = pluginsTypeSig(result, typer, mdef, WildcardType)
       // Assign the moduleClass info (templateSig returns a ClassInfoType)
       val clazz = moduleSym.moduleClass
-      clazz setInfo result
+      clazz setInfo pluginsTp
       // clazz.tpe returns a `ModuleTypeRef(clazz)`, a typeRef that links to the module class `clazz`
       // (clazz.info would the ClassInfoType, which is not what should be assigned to the module symbol)
       clazz.tpe
@@ -1134,7 +1136,7 @@ trait Namers extends MethodSynthesis {
         typer.computeMacroDefType(ddef, resTpFromOverride)
       }
 
-      thisMethodType({
+      val res = thisMethodType({
         val rt = (
           if (!tpt.isEmpty) {
             methResTp
@@ -1150,6 +1152,7 @@ trait Namers extends MethodSynthesis {
           rt.withAnnotation(AnnotationInfo(uncheckedVarianceClass.tpe, List(), List()))
         else rt
       })
+      pluginsTypeSig(res, typer, ddef, methResTp)
     }
 
     /**
@@ -1286,7 +1289,7 @@ trait Namers extends MethodSynthesis {
 
     private def valDefSig(vdef: ValDef) = {
       val ValDef(_, _, tpt, rhs) = vdef
-      if (tpt.isEmpty) {
+      val result = if (tpt.isEmpty) {
         if (rhs.isEmpty) {
           MissingParameterOrValTypeError(tpt)
           ErrorType
@@ -1295,6 +1298,8 @@ trait Namers extends MethodSynthesis {
       } else {
         typer.typedType(tpt).tpe
       }
+      pluginsTypeSig(result, typer, vdef, if (tpt.isEmpty) WildcardType else result)
+
     }
 
     //@M! an abstract type definition (abstract type member/type parameter)
@@ -1328,7 +1333,8 @@ trait Namers extends MethodSynthesis {
       // However, separate compilation requires the symbol info to be
       // loaded to do this check, but loading the info will probably
       // lead to spurious cyclic errors.  So omit the check.
-      GenPolyType(tparamSyms, tp)
+      val res = GenPolyType(tparamSyms, tp)
+      pluginsTypeSig(res, typer, tdef, WildcardType)
     }
 
     private def importSig(imp: Import) = {