IDEA-91742 (correct conversion of extension methods)

java/java-psi-api/src/com/intellij/psi/util/PsiUtil.java

@@ -966,10 +966,15 @@ public final class PsiUtil extends PsiUtilCore {
   }
 
   public static boolean isExtensionMethod(@Nullable final PsiMethod method) {
-    if (method == null) return false;
+    return findExtensionMethodMarker(method) != null;
+  }
+
+  @Nullable
+  public static PsiJavaToken findExtensionMethodMarker(@Nullable final PsiMethod method) {
+    if (method == null) return null;
     final PsiCodeBlock body = method.getBody();
-    if (body == null) return false;
+    if (body == null) return null;
     final PsiElement previous = PsiTreeUtil.skipSiblingsBackward(body, PsiComment.class, PsiWhiteSpace.class);
-    return isJavaToken(previous, JavaTokenType.DEFAULT_KEYWORD);
+    return previous instanceof PsiJavaToken && isJavaToken(previous, JavaTokenType.DEFAULT_KEYWORD) ? (PsiJavaToken)previous : null;
   }
 }

plugins/IntentionPowerPak/src/com/siyeh/ipp/interfacetoclass/ConvertInterfaceToClassIntention.java

@@ -19,6 +19,7 @@ import com.intellij.openapi.project.Project;
 import com.intellij.psi.*;
 import com.intellij.psi.search.SearchScope;
 import com.intellij.psi.search.searches.ClassInheritorsSearch;
+import com.intellij.psi.util.PsiUtil;
 import com.intellij.refactoring.util.CommonRefactoringUtil;
 import com.intellij.util.IncorrectOperationException;
 import com.intellij.util.Query;
@@ -31,16 +32,14 @@ import java.util.Collection;
 
 public class ConvertInterfaceToClassIntention extends Intention {
 
-  private static void changeInterfaceToClass(PsiClass anInterface)
-    throws IncorrectOperationException {
+  private static void changeInterfaceToClass(PsiClass anInterface) throws IncorrectOperationException {
     final PsiIdentifier nameIdentifier = anInterface.getNameIdentifier();
     assert nameIdentifier != null;
     final PsiElement whiteSpace = nameIdentifier.getPrevSibling();
     assert whiteSpace != null;
     final PsiElement interfaceToken = whiteSpace.getPrevSibling();
     assert interfaceToken != null;
-    final PsiKeyword interfaceKeyword =
-      (PsiKeyword)interfaceToken.getOriginalElement();
+    final PsiKeyword interfaceKeyword = (PsiKeyword)interfaceToken.getOriginalElement();
     final Project project = anInterface.getProject();
     final JavaPsiFacade psiFacade = JavaPsiFacade.getInstance(project);
     final PsiElementFactory factory = psiFacade.getElementFactory();
@@ -52,16 +51,25 @@ public class ConvertInterfaceToClassIntention extends Intention {
       return;
     }
     classModifierList.setModifierProperty(PsiModifier.ABSTRACT, true);
+
     final PsiElement parent = anInterface.getParent();
     if (parent instanceof PsiClass) {
       classModifierList.setModifierProperty(PsiModifier.STATIC, true);
     }
+
     final PsiMethod[] methods = anInterface.getMethods();
     for (final PsiMethod method : methods) {
+      final PsiJavaToken marker = PsiUtil.findExtensionMethodMarker(method);
       final PsiModifierList modifierList = method.getModifierList();
       modifierList.setModifierProperty(PsiModifier.PUBLIC, true);
-      modifierList.setModifierProperty(PsiModifier.ABSTRACT, true);
+      if (marker != null) {
+        marker.delete();
+      }
+      else {
+        modifierList.setModifierProperty(PsiModifier.ABSTRACT, true);
+      }
     }
+
     final PsiField[] fields = anInterface.getFields();
     for (final PsiField field : fields) {
       final PsiModifierList modifierList = field.getModifierList();
@@ -71,6 +79,7 @@ public class ConvertInterfaceToClassIntention extends Intention {
         modifierList.setModifierProperty(PsiModifier.FINAL, true);
       }
     }
+
     final PsiClass[] innerClasses = anInterface.getInnerClasses();
     for (PsiClass innerClass : innerClasses) {
       final PsiModifierList modifierList = innerClass.getModifierList();

plugins/IntentionPowerPak/test/com/siyeh/ipp/interfaceToClass/Basic.java

@@ -0,0 +1,19 @@
+/*
+ * Copyright 2000-2012 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.
+ */
+
+public interface I<caret> {
+  void m();
+}

plugins/IntentionPowerPak/test/com/siyeh/ipp/interfaceToClass/Basic_after.java

@@ -0,0 +1,19 @@
+/*
+ * Copyright 2000-2012 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.
+ */
+
+public abstract class I {
+  public abstract void m();
+}

plugins/IntentionPowerPak/test/com/siyeh/ipp/interfaceToClass/ExtensionMethods.java

@@ -0,0 +1,21 @@
+/*
+ * Copyright 2000-2012 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.
+ */
+
+public interface I<caret> {
+  void m() default {
+    System.out.println("Hi there.");
+  }
+}

plugins/IntentionPowerPak/test/com/siyeh/ipp/interfaceToClass/ExtensionMethods_after.java

@@ -0,0 +1,21 @@
+/*
+ * Copyright 2000-2012 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.
+ */
+
+public abstract class I {
+  public void m() {
+    System.out.println("Hi there.");
+  }
+}

plugins/IntentionPowerPak/test/com/siyeh/ipp/interfacetoclass/ConvertInterfaceToClass.java

@@ -1,6 +0,0 @@
-package com.siyeh.ipp.interfacetoclass;
-
-public interface ConvertInterfaceToClass
-{
-
-}

plugins/IntentionPowerPak/test/com/siyeh/ipp/interfacetoclass/ConvertInterfaceToClassImpl.java

@@ -1,14 +0,0 @@
-package com.siyeh.ipp.interfacetoclass;
-
-import javax.swing.AbstractAction;
-import java.awt.event.ActionEvent;
-
-// make me readonly
-public class ConvertInterfaceToClassImpl extends AbstractAction
-        implements ConvertInterfaceToClass
-{
-
-    public void actionPerformed(ActionEvent e)
-    {
-    }
-}

plugins/IntentionPowerPak/testSrc/com/siyeh/ipp/interfacetoclass/ConvertInterfaceToClassTest.java

@@ -0,0 +1,34 @@
+/*
+ * Copyright 2000-2012 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.siyeh.ipp.interfacetoclass;
+
+import com.siyeh.IntentionPowerPackBundle;
+import com.siyeh.ipp.IPPTestCase;
+
+public class ConvertInterfaceToClassTest extends IPPTestCase {
+  public void testBasic() { doTest(); }
+  public void testExtensionMethods() { doTest(); }
+
+  @Override
+  protected String getRelativePath() {
+    return "interfaceToClass";
+  }
+
+  @Override
+  protected String getIntentionName() {
+    return IntentionPowerPackBundle.message("convert.interface.to.class.intention.name");
+  }
+}