java 8: allow to cast to intersection types

java/java-psi-api/src/com/intellij/psi/util/TypeConversionUtil.java

@@ -105,6 +105,12 @@ public class TypeConversionUtil {
       final int toTypeRank = getTypeRank(toType);
       if (!toIsPrimitive) {
         if (fromTypeRank == toTypeRank) return true;
+        if (toType instanceof PsiIntersectionType) {
+          for (PsiType type : ((PsiIntersectionType)toType).getConjuncts()) {
+            if (!areTypesConvertible(fromType, type)) return false;
+          }
+          return true;
+        }
         // JLS 5.5: A value of a primitive type can be cast to a reference type by boxing conversion(see 5.1.7)
         if (!(toType instanceof PsiClassType)) return false;
         PsiClass toClass = ((PsiClassType)toType).resolve();

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/genericsHighlighting8/CastToIntersectionType.java

@@ -0,0 +1,10 @@
+import java.io.Serializable;
+
+class X {
+
+  <T extends Integer & Serializable> void foo(T param) {}
+
+  {
+    foo((Integer & Serializable)0);
+  }
+}

java/java-tests/testSrc/com/intellij/codeInsight/daemon/lambda/GenericsHighlighting8Test.java

@@ -739,6 +739,10 @@ public class GenericsHighlighting8Test extends LightDaemonAnalyzerTestCase {
     doTest();
   }
 
+  public void testCastToIntersectionType() throws Exception {
+    doTest();
+  }
+
   private void doTest() {
     doTest(false);
   }