inline: don't insert cast to var (IDEA-192159)

java/java-impl/src/com/intellij/refactoring/util/InlineUtil.java

@@ -160,6 +160,9 @@ public class InlineUtil {
     if (typeElement == null) {
       typeElement = factory.createTypeElement(variable.getType());
     }
+    else if (typeElement.isInferredType()) {
+      return expr;
+    }
     castTypeElement.replace(typeElement);
     final PsiExpression operand = cast.getOperand();
     assert operand != null;

java/java-tests/testData/refactoring/inlineLocal/NoCastWithVar.java

@@ -0,0 +1,11 @@
+
+import java.util.Arrays;
+import java.util.stream.Stream;
+
+class Main {
+    public static void main(String[] args) {
+        var stream1 = Stream.of(Arrays.asList("1"), Arrays.asList(1));
+        var stream2 = stre<caret>am1.map(list -> list);
+
+    }
+}

java/java-tests/testData/refactoring/inlineLocal/NoCastWithVar.java.after

@@ -0,0 +1,10 @@
+
+import java.util.Arrays;
+import java.util.stream.Stream;
+
+class Main {
+    public static void main(String[] args) {
+        var stream2 = Stream.of(Arrays.asList("1"), Arrays.asList(1)).map(list -> list);
+
+    }
+}

java/java-tests/testSrc/com/intellij/java/refactoring/inline/InlineLocalTest.java

@@ -189,40 +189,30 @@ public class InlineLocalTest extends LightCodeInsightTestCase {
   }
   
   public void testLambdaExpr() {
-    doTest(true);
+    doTest(true, LanguageLevel.JDK_1_8);
   }
   
   public void testLambdaExprAsRefQualifier() {
-    doTest(true);
+    doTest(true, LanguageLevel.JDK_1_8);
   }
 
   public void testMethodRefAsRefQualifier() {
-    doTest(true);
+    doTest(true, LanguageLevel.JDK_1_8);
   }
 
   public void testLocalVarInsideLambdaBody() {
-    doTest(true);
+    doTest(true, LanguageLevel.JDK_1_8);
   }
 
   public void testLocalVarInsideLambdaBody1() {
-    doTest(true);
+    doTest(true, LanguageLevel.JDK_1_8);
   }
   
-  public void testLocalVarInsideLambdaBody2() {
-    doTest(true);
-  }
-
-  public void testLocalVarUsedInLambdaBody() {
-    doTest(true);
-  }
-
-  public void testCastAroundLambda() {
-    doTest(true);
-  }
-
-  public void testNoCastAroundLambda() {
-    doTest(true);
-  }
+  public void testLocalVarInsideLambdaBody2() { doTest(true, LanguageLevel.JDK_1_8); }
+  public void testLocalVarUsedInLambdaBody() { doTest(true, LanguageLevel.JDK_1_8); }
+  public void testCastAroundLambda() { doTest(true, LanguageLevel.JDK_1_8); }
+  public void testNoCastAroundLambda() { doTest(true, LanguageLevel.JDK_1_8); }
+  public void testNoCastWithVar() { doTest(true, LanguageLevel.JDK_10); }
 
   public void testUncheckedCast() {
     doTest(true);
@@ -320,7 +310,11 @@ public class InlineLocalTest extends LightCodeInsightTestCase {
   }
 
   private void doTest(final boolean inlineDef) {
-    setLanguageLevel(LanguageLevel.JDK_1_7);
+    doTest(inlineDef, LanguageLevel.JDK_1_7);
+  }
+
+  private void doTest(final boolean inlineDef, LanguageLevel languageLevel) {
+    setLanguageLevel(languageLevel);
     String name = getTestName(false);
     String fileName = "/refactoring/inlineLocal/" + name + ".java";
     configureByFile(fileName);