IDEA-112552 "Replace with lambda" should use expression lambda when possible

java/java-analysis-impl/src/com/intellij/codeInspection/AnonymousCanBeLambdaInspection.java

@@ -161,10 +161,14 @@ public class AnonymousCanBeLambdaInspection extends BaseJavaBatchLocalInspection
 
         final PsiStatement[] statements = body.getStatements();
         PsiElement copy = body.copy();
-        if (statements.length == 1 && statements[0] instanceof PsiReturnStatement) {
-          PsiExpression value = ((PsiReturnStatement)statements[0]).getReturnValue();
-          if (value != null) {
-            copy = value.copy();
+        if (statements.length == 1) {
+          if (statements[0] instanceof PsiReturnStatement) {
+            PsiExpression value = ((PsiReturnStatement)statements[0]).getReturnValue();
+            if (value != null) {
+              copy = value.copy();
+            }
+          } else if (statements[0] instanceof PsiExpressionStatement) {
+            copy = ((PsiExpressionStatement)statements[0]).getExpression().copy();
           }
         }
 

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/anonymous2lambda/afterCallToDefaultFromFunctionalInterfaceInsideInheritor.java

@@ -7,9 +7,7 @@ class Test {
 
   interface InOutEx extends InOut {
     InOut bind() {
-      return () -> {
-        foo();
-      };
+      return () -> foo();
     }
   }
 }

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/anonymous2lambda/afterCallToStaticFromFunctionalInterface.java

@@ -6,8 +6,6 @@ class Test {
   }
 
   InOut bind() {
-    return () -> {
-      InOut.foo();
-    };
+    return () -> InOut.foo();
   }
 }

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/anonymous2lambda/afterFinalFieldInitializedBeforeAnonymInConstructor.java

@@ -4,10 +4,7 @@ class HelloLambda {
 
   HelloLambda() {
     x = 1;
-    Runnable r = () -> {
-      System.out.println(x);
-
-    };
+    Runnable r = () -> System.out.println(x);
 
   }
 

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/anonymous2lambda/afterForwardStaticFieldReference.java

@@ -1,7 +1,5 @@
 // "Replace with lambda" "true"
 class HelloLambda {
-  private final Runnable r = () -> {
-    System.out.println(x);
-  };
+  private final Runnable r = () -> System.out.println(x);
   private static int x = 0;
 }

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/anonymous2lambda/afterRunnable.java

@@ -1,8 +1,6 @@
 // "Replace with lambda" "true"
 class Test {
   {
-    Runnable r = () -> {
-      System.out.println("");
-    };
+    Runnable r = () -> System.out.println("");
   }
 }

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/anonymous2lambda/afterRunnableInArrayInitializer.java

@@ -1,8 +1,6 @@
 // "Replace with lambda" "true"
 class Test {
   {
-    Runnable[] r = new Runnable[] {() -> {
-      System.out.println("");
-    }};
+    Runnable[] r = new Runnable[] {() -> System.out.println("")};
   }
 }