Javadoc: java static name resolution

[Jakob Odersky <jodersky@gmail.com>: remove obsolete comments and fix tests]

Author: adriaanm

src/compiler/scala/tools/nsc/javac/JavaParsers.scala

@@ -600,26 +600,8 @@ trait JavaParsers extends ast.parser.ParsersCommon with JavaScanners {
         Import(Ident(cdef.name.toTermName), ImportSelector.wildList)
       }
 
-    // Importing the companion object members cannot be done uncritically: see
-    // ticket #2377 wherein a class contains two static inner classes, each of which
-    // has a static inner class called "Builder" - this results in an ambiguity error
-    // when each performs the import in the enclosing class's scope.
-    //
-    // To address this I moved the import Companion._ inside the class, as the first
-    // statement.  This should work without compromising the enclosing scope, but may (?)
-    // end up suffering from the same issues it does in scala - specifically that this
-    // leaves auxiliary constructors unable to access members of the companion object
-    // as unqualified identifiers.
-    def addCompanionObject(statics: List[Tree], cdef: ClassDef): List[Tree] = {
-      def implWithImport(importStmt: Tree) = deriveTemplate(cdef.impl)(importStmt :: _)
-      // if there are no statics we can use the original cdef, but we always
-      // create the companion so import A._ is not an error (see ticket #1700)
-      val cdefNew =
-        if (statics.isEmpty) cdef
-        else deriveClassDef(cdef)(_ => implWithImport(importCompanionObject(cdef)))
-
-      List(makeCompanionObject(cdefNew, statics), cdefNew)
-    }
+    def addCompanionObject(statics: List[Tree], cdef: ClassDef): List[Tree] =
+      List(makeCompanionObject(cdef, statics), cdef)
 
     def importDecl(): List[Tree] = {
       accept(IMPORT)

src/compiler/scala/tools/nsc/typechecker/Contexts.scala

@@ -1016,7 +1016,16 @@ trait Contexts { self: Analyzer =>
           || unit.exists && s.sourceFile != unit.source.file
         )
       )
-      def lookupInPrefix(name: Name)    = pre member name filter qualifies
+      def lookupInPrefix(name: Name)    = {
+        val sym = pre.member(name).filter(qualifies)
+        def isNonPackageNoModuleClass(sym: Symbol) =
+          sym.isClass && !sym.isModuleClass && !sym.isPackageClass
+        if (!sym.exists && unit.isJava && isNonPackageNoModuleClass(pre.typeSymbol)) {
+          // TODO factor out duplication with Typer::inCompanionForJavaStatic
+          val pre1 = companionSymbolOf(pre.typeSymbol, this).typeOfThis
+          pre1.member(name).filter(qualifies).andAlso(_ => pre = pre1)
+        } else sym
+      }
       def accessibleInPrefix(s: Symbol) = isAccessible(s, pre, superAccess = false)
 
       def searchPrefix = {

src/compiler/scala/tools/nsc/typechecker/Typers.scala

@@ -4719,6 +4719,16 @@ 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"inCompanionJavaStatic($pre, $cls, $name) = $res ${res.debugFlagString}")
+        }
+
       /* Attribute a selection where `tree` is `qual.name`.
        * `qual` is already attributed.
        */
@@ -4745,7 +4755,7 @@ 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)

test/files/pos/t2377b/Q.java

@@ -0,0 +1,13 @@
+public class Q {
+
+  public static class Builder {}
+
+  public static class Inner {
+    public static class Builder { public void innerMethod() {} }
+    public Builder foo() { return new Builder(); } // this line gives an error, that Builder is ambiguous
+
+    public Inner.Builder viaSelect() { return new Builder(); } // this line gives an error, that Builder is ambiguous
+  }
+
+}
+

test/files/pos/t2377b/a.scala

@@ -0,0 +1,5 @@
+object Test {
+  (new Q.Inner).foo.innerMethod
+  (new Q.Inner).viaSelect.innerMethod
+
+}