generify: collapse to diamond when applicable

java/java-tests/testData/refactoring/typeCook/convertToDiamond/after/Test.1.items

@@ -0,0 +1 @@
+java.util.ArrayList<java.lang.String>\nnew

java/java-tests/testData/refactoring/typeCook/convertToDiamond/after/Test.items

@@ -0,0 +1 @@
+java.util.ArrayList\nnew

java/java-tests/testData/refactoring/typeCook/convertToDiamond/after/test.java

@@ -0,0 +1,6 @@
+import java.util.ArrayList;
+
+class Test
+{
+  ArrayList<String> l = new ArrayList<>();
+}

java/java-tests/testData/refactoring/typeCook/convertToDiamond/before/test.java

@@ -0,0 +1,6 @@
+import java.util.ArrayList;
+
+class Test
+{
+  ArrayList<String> l = new ArrayList();
+}

java/java-tests/testSrc/com/intellij/refactoring/TypeCookTest.java

@@ -17,9 +17,11 @@ package com.intellij.refactoring;
 
 import com.intellij.JavaTestUtil;
 import com.intellij.openapi.fileEditor.FileDocumentManager;
+import com.intellij.openapi.roots.LanguageLevelProjectExtension;
 import com.intellij.openapi.util.io.FileUtil;
 import com.intellij.openapi.vfs.LocalFileSystem;
 import com.intellij.openapi.vfs.VirtualFile;
+import com.intellij.pom.java.LanguageLevel;
 import com.intellij.psi.PsiClass;
 import com.intellij.psi.search.GlobalSearchScope;
 import com.intellij.refactoring.typeCook.Settings;
@@ -667,6 +669,18 @@ public class TypeCookTest extends MultiFileTestCase {
         start();
   }
 
+  public void testConvertToDiamond() throws Exception {
+    final LanguageLevelProjectExtension levelProjectExtension = LanguageLevelProjectExtension.getInstance(getProject());
+    final LanguageLevel oldLevel = levelProjectExtension.getLanguageLevel();
+    try {
+      levelProjectExtension.setLanguageLevel(LanguageLevel.JDK_1_8);
+      start();
+    }
+    finally {
+      levelProjectExtension.setLanguageLevel(oldLevel);
+    }
+  }
+
   public void start() throws Exception {
     start(false);
   }