Merge pull request #140 from crazyproger/KT-1985

KT-1985 Creating class body in time of override/implement, if necessary

compiler/frontend/src/org/jetbrains/jet/lang/psi/JetPsiFactory.java

@@ -147,6 +147,11 @@ public class JetPsiFactory {
         return function.getBodyExpression();
     }
 
+    public static JetClassBody createEmptyClassBody(Project project) {
+        JetClass aClass = createClass(project, "class A(){}");
+        return aClass.getBody();
+    }
+
     public static JetParameter createParameter(Project project, String name, String type) {
         JetNamedFunction function = createFunction(project, "fun foo(" + name + " : " + type + ") {}");
         return function.getValueParameters().get(0);

idea/src/org/jetbrains/jet/plugin/codeInsight/OverrideImplementMethodsHandler.java

@@ -68,9 +68,10 @@ public abstract class OverrideImplementMethodsHandler implements LanguageCodeIns
             JetClassOrObject classOrObject,
             List<DescriptorClassMember> selectedElements
     ) {
-        final JetClassBody body = classOrObject.getBody();
+        JetClassBody body = classOrObject.getBody();
+        Project project = classOrObject.getProject();
         if (body == null) {
-            return;
+            body = JetPsiFactory.createEmptyClassBody(project);
         }
 
         PsiElement afterAnchor = findInsertAfterAnchor(editor, body);
@@ -87,6 +88,11 @@ public abstract class OverrideImplementMethodsHandler implements LanguageCodeIns
             elementsToCompact.add((JetElement) added);
         }
         ReferenceToClassesShortening.compactReferenceToClasses(elementsToCompact);
+
+        if (!body.isPhysical()) {
+            classOrObject.add(JetPsiFactory.createWhiteSpace(project));
+            classOrObject.add(body);
+        }
     }
 
     @Nullable

idea/testData/codeInsight/overrideImplement/emptyClassBodyFunctionMethod.kt

@@ -0,0 +1,6 @@
+// From KT-1254
+trait T {
+    fun Foo() : (String) -> Unit
+}
+
+class C : <caret>T

idea/testData/codeInsight/overrideImplement/emptyClassBodyFunctionMethod.kt.after

@@ -0,0 +1,10 @@
+// From KT-1254
+trait T {
+    fun Foo() : (String) -> Unit
+}
+
+class C : T {
+    override fun Foo(): (String) -> Unit {
+        throw UnsupportedOperationException()
+    }
+}

idea/tests/org/jetbrains/jet/plugin/codeInsight/OverrideImplementTest.java

@@ -54,6 +54,10 @@ public class OverrideImplementTest extends LightCodeInsightFixtureTestCase {
         myFixture.setTestDataPath(PluginTestCaseBase.getTestDataPathBase() + "/codeInsight/overrideImplement");
     }
 
+    public void testEmptyClassBodyFunctionMethod() {
+        doImplementFileTest();
+    }
+
     public void testFunctionMethod() {
         doImplementFileTest();
     }