diff --git a/java/typeMigration/src/META-INF/TypeMigration.xml b/java/typeMigration/src/META-INF/TypeMigration.xml
index c27c63eb1afc..46042d875b03 100644
--- a/java/typeMigration/src/META-INF/TypeMigration.xml
+++ b/java/typeMigration/src/META-INF/TypeMigration.xml
@@ -8,6 +8,7 @@
+
diff --git a/java/typeMigration/src/com/intellij/refactoring/typeMigration/rules/VoidConversionRule.java b/java/typeMigration/src/com/intellij/refactoring/typeMigration/rules/VoidConversionRule.java
new file mode 100644
index 000000000000..27fe8801bec4
--- /dev/null
+++ b/java/typeMigration/src/com/intellij/refactoring/typeMigration/rules/VoidConversionRule.java
@@ -0,0 +1,84 @@
+/*
+ * Copyright 2000-2016 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.
+ */
+package com.intellij.refactoring.typeMigration.rules;
+
+import com.intellij.codeInspection.dataFlow.ControlFlowAnalyzer;
+import com.intellij.psi.*;
+import com.intellij.psi.search.PsiElementProcessor;
+import com.intellij.psi.util.PsiTreeUtil;
+import com.intellij.refactoring.typeMigration.TypeConversionDescriptorBase;
+import com.intellij.refactoring.typeMigration.TypeEvaluator;
+import com.intellij.refactoring.typeMigration.TypeMigrationLabeler;
+import com.intellij.util.IncorrectOperationException;
+import com.siyeh.ig.controlflow.UnnecessaryReturnInspection;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+/**
+ * @author Dmitry Batkovich
+ */
+public class VoidConversionRule extends TypeConversionRule {
+ @Nullable
+ @Override
+ public TypeConversionDescriptorBase findConversion(PsiType from,
+ PsiType to,
+ PsiMember member,
+ PsiExpression context,
+ TypeMigrationLabeler labeler) {
+ if (PsiType.VOID.equals(to) && context.getParent() instanceof PsiReturnStatement) {
+ final boolean isPure = PsiTreeUtil.processElements(context, new PsiElementProcessor() {
+ @Override
+ public boolean execute(@NotNull PsiElement element) {
+ if (element instanceof PsiPrefixExpression) {
+ return analyzeUnaryExpressionOperand(((PsiPrefixExpression)element).getOperand());
+ }
+ if (element instanceof PsiPostfixExpression) {
+ return analyzeUnaryExpressionOperand(((PsiPostfixExpression)element).getOperand());
+ }
+ if (element instanceof PsiMethodCallExpression) {
+ final PsiMethod method = ((PsiMethodCallExpression)element).resolveMethod();
+ return method != null && ControlFlowAnalyzer.isPure(method);
+ }
+ return true;
+ }
+
+ private boolean analyzeUnaryExpressionOperand(PsiExpression operand) {
+ if (!(operand instanceof PsiReferenceExpression)) return false;
+ final PsiElement resolved = ((PsiReferenceExpression)operand).resolve();
+ return !(resolved instanceof PsiField);
+ }
+ });
+ if (isPure) {
+ return new TypeConversionDescriptorBase() {
+ @Override
+ public PsiExpression replace(PsiExpression expression, @NotNull TypeEvaluator evaluator) throws IncorrectOperationException {
+ final PsiElement parent = expression.getParent();
+ if (parent instanceof PsiReturnStatement) {
+ expression.delete();
+ if (UnnecessaryReturnInspection.isReturnRedundant((PsiReturnStatement)parent, false, null)) {
+ parent.delete();
+ }
+ }
+ return null;
+ }
+ };
+ } else {
+ return null;
+ }
+ }
+ return null;
+ }
+}
diff --git a/java/typeMigration/test/com/intellij/refactoring/TypeMigrationTest.java b/java/typeMigration/test/com/intellij/refactoring/TypeMigrationTest.java
index 2d999892902a..e91b68c1ff1d 100644
--- a/java/typeMigration/test/com/intellij/refactoring/TypeMigrationTest.java
+++ b/java/typeMigration/test/com/intellij/refactoring/TypeMigrationTest.java
@@ -826,6 +826,10 @@ public class TypeMigrationTest extends TypeMigrationTestBase {
doTestFieldType("fooDontMigrateName", PsiType.BOOLEAN);
}
+ public void testMethodMigrationToVoidWithUnusedReturns() {
+ doTestMethodType("toVoidMethod", PsiType.VOID);
+ }
+
public void testMigrationToSuper() {
doTestFieldType("b", myJavaFacade.getElementFactory().createTypeFromText("Test.A", null));
}
diff --git a/java/typeMigration/testData/refactoring/typeMigration/methodMigrationToVoidWithUnusedReturns/after/Test.items b/java/typeMigration/testData/refactoring/typeMigration/methodMigrationToVoidWithUnusedReturns/after/Test.items
new file mode 100644
index 000000000000..af6da3191a83
--- /dev/null
+++ b/java/typeMigration/testData/refactoring/typeMigration/methodMigrationToVoidWithUnusedReturns/after/Test.items
@@ -0,0 +1,9 @@
+Types:
+PsiMethod:toVoidMethod : void
+PsiMethodCallExpression:toVoidMethod() : void
+
+Conversions:
+
+New expression type changes:
+Fails:
+"" + String.valueOf(999)->void
diff --git a/java/typeMigration/testData/refactoring/typeMigration/methodMigrationToVoidWithUnusedReturns/after/test.java b/java/typeMigration/testData/refactoring/typeMigration/methodMigrationToVoidWithUnusedReturns/after/test.java
new file mode 100644
index 000000000000..9a41034f67a0
--- /dev/null
+++ b/java/typeMigration/testData/refactoring/typeMigration/methodMigrationToVoidWithUnusedReturns/after/test.java
@@ -0,0 +1,11 @@
+class Test {
+
+ public void toVoidMethod() {
+ int j = 0;
+ return "" + String.valueOf(999);
+ }
+
+ public void main(String[] args) {
+ toVoidMethod();
+ }
+}
diff --git a/java/typeMigration/testData/refactoring/typeMigration/methodMigrationToVoidWithUnusedReturns/before/test.java b/java/typeMigration/testData/refactoring/typeMigration/methodMigrationToVoidWithUnusedReturns/before/test.java
new file mode 100644
index 000000000000..dc030e222267
--- /dev/null
+++ b/java/typeMigration/testData/refactoring/typeMigration/methodMigrationToVoidWithUnusedReturns/before/test.java
@@ -0,0 +1,11 @@
+class Test {
+
+ public String toVoidMethod() {
+ int j = 0;
+ return "" + String.valueOf(999);
+ }
+
+ public void main(String[] args) {
+ toVoidMethod();
+ }
+}
diff --git a/plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/controlflow/UnnecessaryReturnInspection.java b/plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/controlflow/UnnecessaryReturnInspection.java
index 5a91e861441a..193be4ee448f 100644
--- a/plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/controlflow/UnnecessaryReturnInspection.java
+++ b/plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/controlflow/UnnecessaryReturnInspection.java
@@ -16,6 +16,7 @@
package com.siyeh.ig.controlflow;
import com.intellij.codeInspection.ui.SingleCheckboxOptionsPanel;
+import com.intellij.openapi.util.Ref;
import com.intellij.psi.*;
import com.intellij.psi.util.FileTypeUtils;
import com.intellij.psi.util.PsiTreeUtil;
@@ -26,6 +27,7 @@ import com.siyeh.ig.InspectionGadgetsFix;
import com.siyeh.ig.fixes.DeleteUnnecessaryStatementFix;
import com.siyeh.ig.psiutils.ControlFlowUtils;
import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
import javax.swing.*;
@@ -85,48 +87,59 @@ public class UnnecessaryReturnInspection extends BaseInspection {
@Override
public void visitReturnStatement(@NotNull PsiReturnStatement statement) {
super.visitReturnStatement(statement);
- if (statement.getReturnValue() != null) {
- return;
+ final Ref constructorRef = Ref.create();
+ if (isReturnRedundant(statement, ignoreInThenBranch, constructorRef)) {
+ registerStatementError(statement, constructorRef.get());
}
- final PsiElement methodParent = PsiTreeUtil.getParentOfType(statement, PsiMethod.class, PsiLambdaExpression.class);
- PsiCodeBlock codeBlock = null;
- final boolean constructor;
- if (methodParent instanceof PsiMethod) {
- final PsiMethod method = (PsiMethod)methodParent;
- codeBlock = method.getBody();
- constructor = method.isConstructor();
- }
- else if (methodParent instanceof PsiLambdaExpression) {
- constructor = false;
- final PsiLambdaExpression lambdaExpression = (PsiLambdaExpression)methodParent;
- final PsiElement lambdaBody = lambdaExpression.getBody();
- if (lambdaBody instanceof PsiCodeBlock) {
- codeBlock = (PsiCodeBlock)lambdaBody;
- }
- }
- else {
- return;
- }
- if (codeBlock == null) {
- return;
- }
- if (!ControlFlowUtils.blockCompletesWithStatement(codeBlock, statement)) {
- return;
- }
- if (ignoreInThenBranch && isInThenBranch(statement)) {
- return;
- }
- registerStatementError(statement, Boolean.valueOf(constructor));
}
- private boolean isInThenBranch(PsiStatement statement) {
- final PsiIfStatement ifStatement =
- PsiTreeUtil.getParentOfType(statement, PsiIfStatement.class, true, PsiMethod.class, PsiLambdaExpression.class);
- if (ifStatement == null) {
- return false;
- }
- final PsiStatement elseBranch = ifStatement.getElseBranch();
- return elseBranch != null && !PsiTreeUtil.isAncestor(elseBranch, statement, true);
+ }
+
+ public static boolean isReturnRedundant(@NotNull PsiReturnStatement statement,
+ boolean ignoreInThenBranch,
+ @Nullable Ref isInConstructorRef) {
+ if (statement.getReturnValue() != null) {
+ return false;
}
+ final PsiElement methodParent = PsiTreeUtil.getParentOfType(statement, PsiMethod.class, PsiLambdaExpression.class);
+ PsiCodeBlock codeBlock = null;
+ if (methodParent instanceof PsiMethod) {
+ final PsiMethod method = (PsiMethod)methodParent;
+ codeBlock = method.getBody();
+ if (isInConstructorRef != null) {
+ isInConstructorRef.set(method.isConstructor());
+ }
+ }
+ else if (methodParent instanceof PsiLambdaExpression) {
+ isInConstructorRef.set(false);
+ final PsiLambdaExpression lambdaExpression = (PsiLambdaExpression)methodParent;
+ final PsiElement lambdaBody = lambdaExpression.getBody();
+ if (lambdaBody instanceof PsiCodeBlock) {
+ codeBlock = (PsiCodeBlock)lambdaBody;
+ }
+ }
+ else {
+ return false;
+ }
+ if (codeBlock == null) {
+ return false;
+ }
+ if (!ControlFlowUtils.blockCompletesWithStatement(codeBlock, statement)) {
+ return false;
+ }
+ if (ignoreInThenBranch && isInThenBranch(statement)) {
+ return false;
+ }
+ return true;
+ }
+
+ private static boolean isInThenBranch(PsiStatement statement) {
+ final PsiIfStatement ifStatement =
+ PsiTreeUtil.getParentOfType(statement, PsiIfStatement.class, true, PsiMethod.class, PsiLambdaExpression.class);
+ if (ifStatement == null) {
+ return false;
+ }
+ final PsiStatement elseBranch = ifStatement.getElseBranch();
+ return elseBranch != null && !PsiTreeUtil.isAncestor(elseBranch, statement, true);
}
}
\ No newline at end of file