Fix race condition in SkylarkType.of

Fix race condition in SkylarkType.of(), whereby .equals() but not same (==) types were created, by making Simple.of() synchronized.

Also make SkylarkType#includes() more robust by using .equals() instead of == (it's a little bit slower in the case of Simple types once fixed, but also works on complex types that don't hash-cons their values).

Also, distinguish SkylarkList (printed as list) and java.util.List (printed as List) and similarly for tuple vs Tuple, when printing types in debugging messages.

--
MOS_MIGRATED_REVID=87490176

1 files changed, 1 insertions, 1 deletions

diff --git a/src/test/java/com/google/devtools/build/lib/syntax/BuildFileASTTest.java b/src/test/java/com/google/devtools/build/lib/syntax/BuildFileASTTest.java
index e32005065c..3d463f3018 100644
--- a/src/test/java/com/google/devtools/build/lib/syntax/BuildFileASTTest.java
+++ b/src/test/java/com/google/devtools/build/lib/syntax/BuildFileASTTest.java
@@ -97,7 +97,7 @@ public class BuildFileASTTest {
 
     assertFalse(buildfile.exec(env, reporter));
     Event e = JunitTestUtils.assertContainsEvent(collector,
-        "unsupported operand type(s) for +: 'int' and 'list'");
+        "unsupported operand type(s) for +: 'int' and 'List'");
     assertEquals(4, e.getLocation().getStartLineAndColumn().getLine());
   }