[java-refactoring] IDEA-350228 Missing method body after moving an instance method from interface to non-abstract class

GitOrigin-RevId: a54261f44b8e07273962d3c8c6c2a3db62d6fccf

java/java-impl-refactorings/src/com/intellij/refactoring/move/moveInstanceMethod/MoveInstanceMethodProcessor.java

@@ -2,6 +2,7 @@
 package com.intellij.refactoring.move.moveInstanceMethod;
 
 import com.intellij.codeInsight.ChangeContextUtil;
+import com.intellij.codeInsight.daemon.impl.quickfix.CreateFromUsageUtils;
 import com.intellij.codeInsight.generation.OverrideImplementUtil;
 import com.intellij.ide.util.EditorHelper;
 import com.intellij.java.refactoring.JavaRefactoringBundle;
@@ -460,6 +461,11 @@ public class MoveInstanceMethodProcessor extends BaseRefactoringProcessor{
       final PsiCodeBlock body = myMethod.getBody();
       if (body != null) {
         replaceReferences(body);
+      } else {
+        if (myMethod.hasModifierProperty(PsiModifier.ABSTRACT) &&
+            !myTargetClass.isInterface() && !myTargetClass.hasModifierProperty(PsiModifier.ABSTRACT)) {
+          CreateFromUsageUtils.setupMethodBody(myMethod);
+        }
       }
 
       final PsiMethod methodCopy = getPatternMethod();

java/java-tests/testData/refactoring/moveInstanceMethod/InterfaceMethodIntoClass.java

@@ -0,0 +1,11 @@
+
+public interface A {
+
+  public void n(A a);
+
+  public void <caret>m(B b);
+}
+
+class B {
+
+}

java/java-tests/testData/refactoring/moveInstanceMethod/InterfaceMethodIntoClass.java.after

@@ -0,0 +1,12 @@
+
+public interface A {
+
+  public void n(A a);
+
+}
+
+class B {
+
+    public void m() {
+    }
+}

java/java-tests/testSrc/com/intellij/java/refactoring/moveMethod/MoveInstanceMethodTest.java

@@ -104,6 +104,10 @@ public class MoveInstanceMethodTest extends LightRefactoringTestCase {
   public void testUsageInAnonymousClass() {
     doTest(true, 0);
   }
+  
+  public void testInterfaceMethodIntoClass() {
+    doTest(true, 0);
+  }
 
   public void testConflictingLocalVariableAndTargetClassField() {
     doTest(true, 0);