From cc44924e944325bbf3296c5bdbd2baa4f013565f Mon Sep 17 00:00:00 2001
From: Martin Odersky <odersky@gmail.com>
Date: Sun, 1 Dec 2019 13:06:58 +0100
Subject: [PATCH] Fix #7650: Don't load toplevel definitions in the empty
 package

Don't load toplevel definitions in the empty package from separate files.
Only take them into consideration if they are compiled in the same run.
---
 .../dotty/tools/dotc/core/SymDenotations.scala    | 15 ++++++++++++---
 compiler/test/dotc/run-test-pickling.blacklist    |  1 +
 tests/pos/i7650/Test_1.scala                      |  1 +
 tests/pos/i7650/Test_2.scala                      |  1 +
 .../toplevel-defs/{Test_2.scala => Test.scala}    |  0
 .../toplevel-defs/{defs_1.scala => defs.scala}    |  0
 tests/run/toplevel-mixed/{A_1.scala => A.scala}   |  0
 tests/run/toplevel-mixed/{B_1.scala => B.scala}   |  0
 .../toplevel-mixed/{Test_2.scala => Test.scala}   |  0
 9 files changed, 15 insertions(+), 3 deletions(-)
 create mode 100644 tests/pos/i7650/Test_1.scala
 create mode 100644 tests/pos/i7650/Test_2.scala
 rename tests/run/toplevel-defs/{Test_2.scala => Test.scala} (100%)
 rename tests/run/toplevel-defs/{defs_1.scala => defs.scala} (100%)
 rename tests/run/toplevel-mixed/{A_1.scala => A.scala} (100%)
 rename tests/run/toplevel-mixed/{B_1.scala => B.scala} (100%)
 rename tests/run/toplevel-mixed/{Test_2.scala => Test.scala} (100%)

diff --git a/compiler/src/dotty/tools/dotc/core/SymDenotations.scala b/compiler/src/dotty/tools/dotc/core/SymDenotations.scala
index 50b940ec9211..c23c4df40e64 100644
--- a/compiler/src/dotty/tools/dotc/core/SymDenotations.scala
+++ b/compiler/src/dotty/tools/dotc/core/SymDenotations.scala
@@ -2122,11 +2122,20 @@ object SymDenotations {
         case pcls :: pobjs1 =>
           if (pcls.isCompleting) recur(pobjs1, acc)
           else {
-            // A package object inherits members from `Any` and `Object` which
-            // should not be accessible from the package prefix.
             val pmembers = pcls.computeNPMembersNamed(name).filterWithPredicate { d =>
+              // Drop members of `Any` and `Object`, as well as top-level definitions
+              // in the empty package that are not defined in the current run.
               val owner = d.symbol.maybeOwner
-              (owner ne defn.AnyClass) && (owner ne defn.ObjectClass)
+              (owner ne defn.AnyClass)
+              && (owner ne defn.ObjectClass)
+              && (
+                (symbol ne defn.EmptyPackageClass)
+                || d.symbol.isDefinedInCurrentRun
+                || d.symbol.associatedFile == null
+                    // if a symbol does not have an associated file, assume it is defined
+                    // in the current run anyway. This typically happens for pickling and from
+                    // tasty tests that generate a fresh symbol and then re-use it in the next run.
+              )
             }
             recur(pobjs1, acc.union(pmembers))
           }
diff --git a/compiler/test/dotc/run-test-pickling.blacklist b/compiler/test/dotc/run-test-pickling.blacklist
index f3e4c7ec847c..31036f89e6dc 100644
--- a/compiler/test/dotc/run-test-pickling.blacklist
+++ b/compiler/test/dotc/run-test-pickling.blacklist
@@ -14,6 +14,7 @@ typeclass-derivation2d.scala
 typeclass-derivation3.scala
 derive-generic.scala
 mixin-forwarder-overload
+toplevel-defs
 t8905
 t10889
 macros-in-same-project1
diff --git a/tests/pos/i7650/Test_1.scala b/tests/pos/i7650/Test_1.scala
new file mode 100644
index 000000000000..01bc62e8e357
--- /dev/null
+++ b/tests/pos/i7650/Test_1.scala
@@ -0,0 +1 @@
+@main def Test() = println("hi")
\ No newline at end of file
diff --git a/tests/pos/i7650/Test_2.scala b/tests/pos/i7650/Test_2.scala
new file mode 100644
index 000000000000..00174769a0f0
--- /dev/null
+++ b/tests/pos/i7650/Test_2.scala
@@ -0,0 +1 @@
+object Test
diff --git a/tests/run/toplevel-defs/Test_2.scala b/tests/run/toplevel-defs/Test.scala
similarity index 100%
rename from tests/run/toplevel-defs/Test_2.scala
rename to tests/run/toplevel-defs/Test.scala
diff --git a/tests/run/toplevel-defs/defs_1.scala b/tests/run/toplevel-defs/defs.scala
similarity index 100%
rename from tests/run/toplevel-defs/defs_1.scala
rename to tests/run/toplevel-defs/defs.scala
diff --git a/tests/run/toplevel-mixed/A_1.scala b/tests/run/toplevel-mixed/A.scala
similarity index 100%
rename from tests/run/toplevel-mixed/A_1.scala
rename to tests/run/toplevel-mixed/A.scala
diff --git a/tests/run/toplevel-mixed/B_1.scala b/tests/run/toplevel-mixed/B.scala
similarity index 100%
rename from tests/run/toplevel-mixed/B_1.scala
rename to tests/run/toplevel-mixed/B.scala
diff --git a/tests/run/toplevel-mixed/Test_2.scala b/tests/run/toplevel-mixed/Test.scala
similarity index 100%
rename from tests/run/toplevel-mixed/Test_2.scala
rename to tests/run/toplevel-mixed/Test.scala