Merge pull request #8784 from retronym/topic/forward-port-ca7dc4d

[forward port] Use Java semantics for imports in .java files

Author: lrytz

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

@@ -1112,7 +1112,8 @@ trait Contexts { self: Analyzer =>
     /** @return None if a cycle is detected, or Some(infos) containing the in-scope implicits at this context */
     private def implicits: Option[List[ImplicitInfo]] = {
       val firstImport = this.firstImport
-      if (owner != outer.owner && owner.isClass && !owner.isPackageClass) {
+      if (unit.isJava) SomeOfNil
+      else if (owner != outer.owner && owner.isClass && !owner.isPackageClass) {
         if (!owner.isInitialized) None
         else savingEnclClass(this) {
           // !!! In the body of `class C(implicit a: A) { }`, `implicitss` returns `List(List(a), List(a), List(<predef..)))`
@@ -1775,9 +1776,13 @@ trait Contexts { self: Analyzer =>
       @inline def current = selectors.head
       @inline def maybeNonLocalMember(nom: Name): Symbol =
         if (qual.tpe.isError) NoSymbol
-        else qual.tpe.nonLocalMember(nom).orElse {
-          if (pos.source.isJava) qual.tpe.companion nonLocalMember nom else NoSymbol
+        else if (pos.source.isJava) {
+          val (_, sym) = NoContext.javaFindMember(qual.tpe, nom, _ => true)
+          // We don't need to propagate the new prefix back out to the result of `Context.lookupSymbol`
+          // because typechecking .java sources doesn't need it.
+          sym
         }
+        else qual.tpe.nonLocalMember(nom)
       while ((selectors ne Nil) && result == NoSymbol) {
         if (current.introduces(name))
           result = maybeNonLocalMember(current.name asTypeOf name)

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

@@ -569,9 +569,14 @@ trait Namers extends MethodSynthesis {
       }
       def checkSelector(s: ImportSelector) = {
         val ImportSelector(from, fromPos, to, _) = s
-        def isValid(original: Name, base: Type) =
-          (base nonLocalMember original.toTermName) != NoSymbol ||
-            (base nonLocalMember original.toTypeName) != NoSymbol
+        def isValid(original: Name, base: Type) = {
+          def lookup(name: Name) =
+            if (context.unit.isJava)
+              NoContext.javaFindMember(base, name, _ => true)._2
+            else
+              base.nonLocalMember(name)
+          lookup(original.toTermName) != NoSymbol || lookup(original.toTypeName) != NoSymbol
+        }
 
         if (!s.isWildcard && base != ErrorType) {
           val okay = isValid(from, base) || context.unit.isJava && (      // Java code...

test/files/neg/java-import-non-existing-selector.check

@@ -0,0 +1,6 @@
+java-import-non-existing-selector/BadClient.java:3: error: cannot find symbol
+import static p1.Test.DoesNotExist;
+^
+  symbol:   static DoesNotExist
+  location: class
+1 error

test/files/neg/java-import-non-existing-selector.flags

@@ -0,0 +1 @@
+-Ypickle-java

test/files/neg/java-import-non-existing-selector/BadClient.java

@@ -0,0 +1,7 @@
+package p1;
+
+import static p1.Test.DoesNotExist;
+
+class BadClient {
+
+}

test/files/neg/java-import-non-existing-selector/Test.java

@@ -0,0 +1,6 @@
+package p1;
+
+public class Test extends Base {}
+class Base {
+  static class I {}
+}

test/files/pos/java-import-static-from-subclass.flags

@@ -0,0 +1 @@
+-Ypickle-java

test/files/pos/java-import-static-from-subclass/Client.java

@@ -0,0 +1,7 @@
+package p1;
+
+import static p1.Test.I;
+
+class Client {
+  void foo(I i) {}
+}

test/files/pos/java-import-static-from-subclass/Test.java

@@ -0,0 +1,6 @@
+package p1;
+
+public class Test extends Base {}
+class Base {
+  static class I {}
+}

test/files/pos/java-import-static-from-subclass/Test.scala

@@ -0,0 +1 @@
+class Test