From 632fee20aa411de2f52ee2ff8f8565a148d185c1 Mon Sep 17 00:00:00 2001
From: Daniil Ovchinnikov <daniil.ovchinnikov@jetbrains.com>
Date: Wed, 14 Dec 2016 19:30:34 +0300
Subject: [PATCH] [groovy] fix expection on super reference in trait without
 supertypes (EA-74829)

---
 .../expressions/GrReferenceExpressionImpl.java         |  4 +++-
 .../lang/highlighting/Gr23HighlightingTest.groovy      | 10 ++++++++++
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/lang/psi/impl/statements/expressions/GrReferenceExpressionImpl.java b/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/lang/psi/impl/statements/expressions/GrReferenceExpressionImpl.java
index 423045a26066..792e44cc1692 100644
--- a/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/lang/psi/impl/statements/expressions/GrReferenceExpressionImpl.java
+++ b/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/lang/psi/impl/statements/expressions/GrReferenceExpressionImpl.java
@@ -262,7 +262,9 @@ public class GrReferenceExpressionImpl extends GrReferenceElementImpl<GrExpressi
 
           PsiClassType[] superTypes = ArrayUtil.mergeArrays(implementsTypes, extendsTypes, PsiClassType.ARRAY_FACTORY);
 
-          return PsiIntersectionType.createIntersection(ArrayUtil.reverseArray(superTypes));
+          if (superTypes.length > 0) {
+            return PsiIntersectionType.createIntersection(ArrayUtil.reverseArray(superTypes));
+          }
         }
         return factory.createType((PsiClass)resolved);
       }
diff --git a/plugins/groovy/test/org/jetbrains/plugins/groovy/lang/highlighting/Gr23HighlightingTest.groovy b/plugins/groovy/test/org/jetbrains/plugins/groovy/lang/highlighting/Gr23HighlightingTest.groovy
index 6ea50bee7e80..b52e95186116 100644
--- a/plugins/groovy/test/org/jetbrains/plugins/groovy/lang/highlighting/Gr23HighlightingTest.groovy
+++ b/plugins/groovy/test/org/jetbrains/plugins/groovy/lang/highlighting/Gr23HighlightingTest.groovy
@@ -475,4 +475,14 @@ class A implements T {}
 new A().foo
 ''', GroovyUnusedDeclarationInspection
   }
+
+  void 'test no exception on super reference in trait without supertypes'() {
+    testHighlighting '''\
+trait SimpleTrait {
+  void foo() {
+    super.<warning descr="Cannot resolve symbol 'foo'">foo</warning>()
+  }
+}
+'''
+  }
 }