IDEA-99186 Ctrl+Space help when implementing/overriding methods

java/java-tests/testData/codeInsight/completion/normal/ImplementViaCompletion.java

@@ -0,0 +1,7 @@
+interface Foo<T> {
+  void run(T t, int myInt);
+}
+
+public class A implements Foo<String> {
+  p<caret>
+}

java/java-tests/testData/codeInsight/completion/normal/ImplementViaCompletion_after.java

@@ -0,0 +1,10 @@
+interface Foo<T> {
+  void run(T t, int myInt);
+}
+
+public class A implements Foo<String> {
+    @Override
+    public void run(String s, int myInt) {
+        <selection>//To change body of implemented methods use File | Settings | File Templates.</selection>
+    }
+}

java/java-tests/testSrc/com/intellij/codeInsight/completion/NormalCompletionTest.groovy

@@ -1316,5 +1316,20 @@ class XInternalError {}
     assert lookup.items.size() == 1
   }
 
+  public void testImplementViaCompletion() {
+    configure()
+    myFixture.assertPreferredCompletionItems 0, 'private', 'protected', 'public', 'public void run'
+    def item = lookup.items[3]
+
+    def p = LookupElementPresentation.renderElement(item)
+    assert p.itemText == 'public void run'
+    assert p.tailText == '(s, myInt) {...}'
+    assert p.typeText == 'Foo'
+
+    lookup.currentItem = item
+    myFixture.type('\n')
+    checkResult()
+  }
+
 
 }