extract light method object: insert result as last statement

java/java-impl/src/com/intellij/refactoring/extractMethodObject/ExtractLightMethodObjectHandler.java

@@ -28,6 +28,7 @@ import com.intellij.openapi.util.TextRange;
 import com.intellij.openapi.util.text.StringUtil;
 import com.intellij.psi.*;
 import com.intellij.psi.codeStyle.CodeStyleManager;
+import com.intellij.psi.codeStyle.JavaCodeStyleManager;
 import com.intellij.psi.controlFlow.*;
 import com.intellij.psi.impl.source.PostprocessReformattingAspect;
 import com.intellij.psi.util.PsiTreeUtil;
@@ -80,9 +81,10 @@ public class ExtractLightMethodObjectHandler {
                                                        @NotNull final PsiCodeFragment fragment,
                                                        final String methodName) throws PrepareFailedException {
     PsiExpression expression = CodeInsightUtil.findExpressionInRange(fragment, 0, fragment.getTextLength());
+    final PsiElementFactory elementFactory = JavaPsiFacade.getElementFactory(project);
     final PsiElement[] elements;
     if (expression != null) {
-      elements = new PsiElement[] {JavaPsiFacade.getElementFactory(project).createStatementFromText(expression.getText() + ";", expression)};
+      elements = new PsiElement[] {elementFactory.createStatementFromText(expression.getText() + ";", expression)};
     } else {
       elements = CodeInsightUtil.findStatementsInRange(fragment, 0, fragment.getTextLength());
     }
@@ -90,6 +92,18 @@ public class ExtractLightMethodObjectHandler {
       return null;
     }
 
+    if (elements[elements.length - 1] instanceof PsiExpressionStatement) {
+      final PsiExpression expr = ((PsiExpressionStatement)elements[elements.length - 1]).getExpression();
+      if (!(expr instanceof PsiAssignmentExpression)) {
+        final PsiType expressionType = expr.getType();
+        if (expressionType != null && expressionType != PsiType.VOID) {
+          final String uniqueResultName = JavaCodeStyleManager.getInstance(project).suggestUniqueVariableName("result", elements[0], true);
+          final String statementText = expressionType.getCanonicalText() + " " + uniqueResultName + " = " + expr.getText() + ";";
+          elements[elements.length - 1] = elements[elements.length - 1].replace(elementFactory.createStatementFromText(statementText, elements[elements.length -1]));
+        }
+      }
+    }
+
     final PsiFile copy = PsiFileFactory.getInstance(project)
       .createFileFromText(file.getName(), file.getFileType(), file.getText(), file.getModificationStamp(), false);
 
@@ -138,7 +152,7 @@ public class ExtractLightMethodObjectHandler {
                                             return "\"variable: \" + " + variable.getName();
                                           }
                                         }, " +");
-    PsiStatement outStatement = JavaPsiFacade.getElementFactory(project).createStatementFromText("System.out.println(" + outputVariables + ");", anchor);
+    PsiStatement outStatement = elementFactory.createStatementFromText("System.out.println(" + outputVariables + ");", anchor);
     outStatement = (PsiStatement)container.addAfter(outStatement, elementsCopy[elementsCopy.length - 1]);
 
     final ExtractMethodObjectProcessor extractMethodObjectProcessor = new ExtractMethodObjectProcessor(project, null, elementsCopy, "") {

java/java-tests/testData/refactoring/extractMethodObject4Debugger/ResultExpr.java

@@ -0,0 +1,25 @@
+/*
+ * Copyright 2000-2014 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+class Sample {
+
+  void a() {
+    System.out.println("<caret>");
+  }
+
+  int foo() {
+    return 1;
+  }
+}

java/java-tests/testData/refactoring/extractMethodObject4Debugger/ResultStatements.java

@@ -0,0 +1,25 @@
+/*
+ * Copyright 2000-2014 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+class Sample {
+
+  void a() {
+    System.out.println("<caret>");
+  }
+
+  int foo() {
+    return 1;
+  }
+}

java/java-tests/testSrc/com/intellij/refactoring/ExtractMethodObject4DebuggerTest.java

@@ -99,11 +99,11 @@ public class ExtractMethodObject4DebuggerTest extends LightRefactoringTestCase {
   }
 
   public void testAnonymousClassParams() throws Exception {
-    doTest("new I() {public void foo(int i) {i++;}};", "new Test().invoke();",
+    doTest("new I() {public void foo(int i) {i++;}};", "I result = new Test().invoke();",
 
            "public class Test {\n" +
-           "        public void invoke() {\n" +
-           "            new I() {\n" +
+           "        public I invoke() {\n" +
+           "            return new I() {\n" +
            "                public void foo(int i) {\n" +
            "                    i++;\n" +
            "                }\n" +
@@ -113,11 +113,44 @@ public class ExtractMethodObject4DebuggerTest extends LightRefactoringTestCase {
   }
 
   public void testInnerClass() throws Exception {
-    doTest("   new In(2).foo()", "new Test().invoke();",
+    doTest("   new I(2).foo()", "new Test().invoke();",
 
            "public class Test {\n" +
            "        public void invoke() {\n" +
-           "            new In(2).foo();\n" +
+           "            new Sample.I(2).foo();\n" +
+           "        }\n" +
+           "    }");
+  }
+
+  public void testResultExpr() throws Exception {
+    doTest("   foo()", "int result = new Test().invoke();",
+
+           "public class Test {\n" +
+           "        public int invoke() {\n" +
+           "            return foo();\n" +
+           "        }\n" +
+           "    }");
+  }
+
+  public void testResultStatements() throws Exception {
+    doTest("int i = 0;\nfoo()", "Test test = new Test().invoke();int i = test.getI();int result = test.getResult();",
+
+           "public class Test {\n" +
+           "        private int i;\n" +
+           "        private int result;\n" +
+           "\n" +
+           "        public int getI() {\n" +
+           "            return i;\n" +
+           "        }\n" +
+           "\n" +
+           "        public int getResult() {\n" +
+           "            return result;\n" +
+           "        }\n" +
+           "\n" +
+           "        public Test invoke() {\n" +
+           "            i = 0;\n" +
+           "            result = foo();\n" +
+           "            return this;\n" +
            "        }\n" +
            "    }");
   }