SI-6168 Retain prefix when parsing types in JVM signatures

When reading Java classfiles, the generic signatures are
used to construct the corresponding Scala type signatures.

In the enclosed test case, the field `SomeClass.f` had
the JVM signature:

    LContext<LSomeClass;>.Field<Ljava.lang.Integer;>;

The parser first (correctly) parsed the prefix as `Context[SomeClass]`.
It then looked up the type symbol for `Field` in that that type. It then
discarded the parsed prefix, and instead used the prefix from the
info of the type symbol: `Context[ParentType]`.

This commit changes the signature parser after the first `.` to
use the result of prior parsing as the prefix.

I've also included a test case with Java static inner classes,
which don't require any special treatment.

4 files changed, 59 insertions, 0 deletions

diff --git a/test/files/run/t6168b/Context.java b/test/files/run/t6168b/Context.java
new file mode 100644
index 0000000000..b3ea22126f
--- /dev/null
+++ b/test/files/run/t6168b/Context.java
@@ -0,0 +1,34 @@
+public class Context<ParentType> {
+    private ParentType parent;
+
+    public Context() {}
+
+    public ParentType getParent() {
+        return parent;
+    }
+
+    public void setParent(ParentType parent) {
+         this.parent = parent;
+    }
+
+    public Field<Integer> intField() {
+        return new Field<Integer>() {
+            @Override
+            public Integer get() {
+                return 0;
+            }
+
+            @Override
+            public ParentType set(Integer t) {
+                return parent;
+            }
+        };
+    }
+
+    public static abstract class Field<T> {
+
+        public abstract T get();
+
+        public abstract Object set(T t);
+    }
+}
\ No newline at end of file
diff --git a/test/files/run/t6168b/JavaTest.java b/test/files/run/t6168b/JavaTest.java
new file mode 100644
index 0000000000..a09fa0382d
--- /dev/null
+++ b/test/files/run/t6168b/JavaTest.java
@@ -0,0 +1,6 @@
+public class JavaTest {
+  public static void main(String[] args) {
+    SomeClass a = new SomeClass();
+    Object b = a.f.set(23);
+  }
+}
\ No newline at end of file
diff --git a/test/files/run/t6168b/SomeClass.java b/test/files/run/t6168b/SomeClass.java
new file mode 100644
index 0000000000..566c55e1c5
--- /dev/null
+++ b/test/files/run/t6168b/SomeClass.java
@@ -0,0 +1,11 @@
+public class SomeClass {
+    private final Context<SomeClass> context = new Context<SomeClass>();
+    {
+        context.setParent(this);
+    }
+
+    public final Context.Field<Integer> f = context.intField();
+
+}
+
+
diff --git a/test/files/run/t6168b/main.scala b/test/files/run/t6168b/main.scala
new file mode 100644
index 0000000000..187e9fe85e
--- /dev/null
+++ b/test/files/run/t6168b/main.scala
@@ -0,0 +1,8 @@
+
+
+object Test extends App {
+  JavaTest.main(null)
+
+  var a1 : SomeClass = new SomeClass
+  var b1 : Object =  a1.f.set(23)
+}