SI-6591 Reify and path-dependent types

Reification scheme changed. Now Select an SelectFromTypeTree trees
reified appropriately, as Select and SelectFromTypeTree accordingly.
Packages and Predef object was excluded in order not to break the
existing reification scheme and not to break tests which rely on it.

Reified free terms can contain flag <stable> to make reified values
become stable identifiers. For example in the case of
reify_newimpl_15.scala

    class C {
      type T
      reify { val v: List[T] = List(2) }
    }

class C reified as free term C$value, and List[C.T] becomes
List[C$value().T], so C$value.apply() need to pass stability test
isExprSafeToInline at scala.reflect.internal.TreeInfo. For this purpose
special case for reified free terms was added to isExprSafeToInline
function.

test run/reify_newipl_30 disabled due to SI-7082
test t6591_4 moved to pending due to SI-7083

14 files changed, 131 insertions, 4 deletions

diff --git a/test/files/run/reify_newimpl_30.check b/test/files/run/reify_newimpl_30.check
index c23af69b08..29baac911e 100644
--- a/test/files/run/reify_newimpl_30.check
+++ b/test/files/run/reify_newimpl_30.check
@@ -1 +1,2 @@
-List(2)
+reflective toolbox has failed:
+unresolved free type variables (namely: C defined by <local Test> in reify_newimpl_30.scala:7:11). have you forgot to use TypeTag annotations for type parameters external to a reifee? if you have troubles tracking free type variables, consider using -Xlog-free-types
diff --git a/test/files/run/reify_newimpl_30.scala b/test/files/run/reify_newimpl_30.scala
index 573d05a630..bc34f1bb6c 100644
--- a/test/files/run/reify_newimpl_30.scala
+++ b/test/files/run/reify_newimpl_30.scala
@@ -1,5 +1,5 @@
 import scala.reflect.runtime.universe._
-import scala.tools.reflect.ToolBox
+import scala.tools.reflect.{ ToolBox, ToolBoxError }
 import scala.tools.reflect.Eval
 
 object Test extends App {
@@ -9,9 +9,10 @@ object Test extends App {
       val code = reify {
         List[C#T](2)
       }
-      println(code.eval)
+      try { println(code.eval) }
+      catch { case e: ToolBoxError => println(e.getMessage) }
     }
 
     new C
   }
-}
\ No newline at end of file
+}
diff --git a/test/files/run/t6591_1.check b/test/files/run/t6591_1.check
new file mode 100644
index 0000000000..b6cb6c286d
--- /dev/null
+++ b/test/files/run/t6591_1.check
@@ -0,0 +1 @@
+Block(List(ValDef(Modifiers(), newTermName("v"), Select(Ident(A), newTypeName("I")), Select(Ident(A), newTermName("impl")))), Ident(newTermName("v")))
diff --git a/test/files/run/t6591_1.scala b/test/files/run/t6591_1.scala
new file mode 100644
index 0000000000..6dd9a1d9fb
--- /dev/null
+++ b/test/files/run/t6591_1.scala
@@ -0,0 +1,19 @@
+import scala.reflect.runtime.universe._
+import scala.tools.reflect.ToolBox
+import scala.tools.reflect.Eval
+
+trait O { trait I }
+
+object A extends O {
+  val impl = new I {}
+}
+
+object Test extends App {
+  val code = reify {
+    val v: A.I = A.impl
+    v
+  }
+  println(showRaw(code.tree))
+
+  val v: A.I = code.eval
+}
diff --git a/test/files/run/t6591_2.check b/test/files/run/t6591_2.check
new file mode 100644
index 0000000000..b2d5797cbf
--- /dev/null
+++ b/test/files/run/t6591_2.check
@@ -0,0 +1 @@
+Block(List(ValDef(Modifiers(), newTermName("v"), SelectFromTypeTree(Ident(A), newTypeName("I")), Select(Apply(Select(New(Ident(A)), nme.CONSTRUCTOR), List()), newTermName("impl")))), Ident(newTermName("v")))
diff --git a/test/files/run/t6591_2.scala b/test/files/run/t6591_2.scala
new file mode 100644
index 0000000000..6214308dab
--- /dev/null
+++ b/test/files/run/t6591_2.scala
@@ -0,0 +1,19 @@
+import scala.reflect.runtime.universe._
+import scala.tools.reflect.ToolBox
+import scala.tools.reflect.Eval
+
+trait O { trait I }
+
+class A extends O {
+  val impl = new I {}
+}
+
+object Test extends App {
+  val code = reify {
+    val v: A#I = (new A).impl
+    v
+  }
+  println(showRaw(code.tree))
+
+  val v: A#I = code.eval
+}
diff --git a/test/files/run/t6591_3.check b/test/files/run/t6591_3.check
new file mode 100644
index 0000000000..a7b594ba65
--- /dev/null
+++ b/test/files/run/t6591_3.check
@@ -0,0 +1 @@
+Block(List(ValDef(Modifiers(), newTermName("v"), Select(This(newTypeName("A")), newTypeName("I")), Apply(Select(New(Select(This(newTypeName("A")), newTypeName("I"))), nme.CONSTRUCTOR), List()))), Ident(newTermName("v")))
diff --git a/test/files/run/t6591_3.scala b/test/files/run/t6591_3.scala
new file mode 100644
index 0000000000..b73a7baf48
--- /dev/null
+++ b/test/files/run/t6591_3.scala
@@ -0,0 +1,17 @@
+import scala.reflect.runtime.universe._
+import scala.tools.reflect.ToolBox
+import scala.tools.reflect.Eval
+
+class O { class I }
+
+object A extends O {
+  val code = reify {
+    val v: I = new I
+    v
+  }
+  println(showRaw(code.tree))
+}
+
+object Test extends App {
+  val v: A.I = A.code.eval
+}
diff --git a/test/files/run/t6591_5.check b/test/files/run/t6591_5.check
new file mode 100644
index 0000000000..8f1c2b3ede
--- /dev/null
+++ b/test/files/run/t6591_5.check
@@ -0,0 +1 @@
+Expr(Block(List(ValDef(Modifiers(), newTermName("v"), Select(Select(This(newTypeName("A")), newTermName("x")), newTypeName("I")), Select(Select(This(newTypeName("scala")), newTermName("Predef")), newTermName("$qmark$qmark$qmark")))), Ident(newTermName("v"))))
diff --git a/test/files/run/t6591_5.scala b/test/files/run/t6591_5.scala
new file mode 100644
index 0000000000..18d6f90a9b
--- /dev/null
+++ b/test/files/run/t6591_5.scala
@@ -0,0 +1,23 @@
+import scala.reflect.runtime.universe._
+import scala.tools.reflect.ToolBox
+import scala.tools.reflect.Eval
+import java.lang.reflect.InvocationTargetException
+
+class O { class I }
+
+object A extends O {
+  val x = new O
+  val code = reify {
+    val v: x.I = ???
+    v
+  }
+  println(showRaw(code))
+}
+
+object Test extends App {
+  try {
+    val v: A.x.I = A.code.eval
+  } catch {
+    case ex: InvocationTargetException if ex.getCause.isInstanceOf[NotImplementedError] =>
+  }
+}
diff --git a/test/files/run/t6591_6.check b/test/files/run/t6591_6.check
new file mode 100644
index 0000000000..5ddf7600f1
--- /dev/null
+++ b/test/files/run/t6591_6.check
@@ -0,0 +1 @@
+Expr(Block(List(ValDef(Modifiers(), newTermName("v"), Select(Select(Ident(newTermName("A")), newTermName("x")), newTypeName("I")), Select(Select(This(newTypeName("scala")), newTermName("Predef")), newTermName("$qmark$qmark$qmark")))), Ident(newTermName("v"))))
diff --git a/test/files/run/t6591_6.scala b/test/files/run/t6591_6.scala
new file mode 100644
index 0000000000..2eee87928d
--- /dev/null
+++ b/test/files/run/t6591_6.scala
@@ -0,0 +1,24 @@
+import scala.language.existentials
+import scala.reflect.runtime.universe._
+import scala.tools.reflect.ToolBox
+import scala.tools.reflect.Eval
+import java.lang.reflect.InvocationTargetException
+
+class O { class I }
+
+class A extends O {
+  val x = new O
+  val code = reify {
+    val v: x.I = ???
+    v
+  }
+  println(showRaw(code))
+}
+
+object Test extends App {
+  try {
+    val v = (new A).code.eval
+  } catch {
+    case ex: InvocationTargetException if ex.getCause.isInstanceOf[NotImplementedError] =>
+  }
+}
diff --git a/test/pending/run/t6591_4.check b/test/pending/run/t6591_4.check
new file mode 100644
index 0000000000..0f1c0489e9
--- /dev/null
+++ b/test/pending/run/t6591_4.check
@@ -0,0 +1 @@
+Expr(Block(List(ValDef(Modifiers(), newTermName("v"), Select(Ident(newTermName("A")), newTypeName("I")), Apply(Select(New(Select(Ident(newTermName("A")), newTypeName("I"))), nme.CONSTRUCTOR), List()))), Ident(newTermName("v"))))
diff --git a/test/pending/run/t6591_4.scala b/test/pending/run/t6591_4.scala
new file mode 100644
index 0000000000..f20c8e6127
--- /dev/null
+++ b/test/pending/run/t6591_4.scala
@@ -0,0 +1,17 @@
+import scala.reflect.runtime.universe._
+import scala.tools.reflect.ToolBox
+import scala.tools.reflect.Eval
+
+class O { class I }
+
+class A extends O {
+  val code = reify {
+    val v: I = new I
+    v
+  }
+  println(showRaw(code))
+}
+
+object Test extends App {
+  val v: A#I = (new A).code.eval
+}