[java-completion] Specific actions to move through lookup options

Fixes IDEA-274076 Provide a way to change default keys used to navigate code completion list

GitOrigin-RevId: ff5cb8d36c3b0f1315b7a1c708501134c15e8e67

platform/lang-impl/src/com/intellij/codeInsight/lookup/impl/LookupActionHandler.java

@@ -44,7 +44,9 @@ public abstract class LookupActionHandler extends EditorActionHandler {
       if (project != null && lookup != null) {
         LookupManager.getInstance(project).hideActiveLookup();
       }
-      myOriginalHandler.execute(editor, caret, dataContext);
+      if (myOriginalHandler != null) {
+        myOriginalHandler.execute(editor, caret, dataContext);
+      }
       return;
     }
 
@@ -103,6 +105,28 @@ public abstract class LookupActionHandler extends EditorActionHandler {
     }
   }
 
+  public static class UpInLookupAction extends EditorAction {
+    public UpInLookupAction() {
+      super(new UpHandler(null) {
+        @Override
+        public boolean isEnabledForCaret(@NotNull Editor editor, @NotNull Caret caret, DataContext dataContext) {
+          return LookupManager.getActiveLookup(editor) != null;
+        }
+      });
+    }
+  }
+
+  public static class DownInLookupAction extends EditorAction {
+    public DownInLookupAction() {
+      super(new DownHandler(null) {
+        @Override
+        public boolean isEnabledForCaret(@NotNull Editor editor, @NotNull Caret caret, DataContext dataContext) {
+          return LookupManager.getActiveLookup(editor) != null;
+        }
+      });
+    }
+  }
+
   private static final class UpDownInEditorHandler extends EditorActionHandler {
     private final boolean myUp;
 
@@ -140,7 +164,9 @@ public abstract class LookupActionHandler extends EditorActionHandler {
     @Override
     protected void executeInLookup(final LookupImpl lookup, DataContext context, Caret caret) {
       if (!UISettings.getInstance().getCycleScrolling() && !lookup.isFocused() && lookup.getList().getSelectedIndex() == 0) {
-        myOriginalHandler.execute(lookup.getEditor(), caret, context);
+        if (myOriginalHandler != null) {
+          myOriginalHandler.execute(lookup.getEditor(), caret, context);
+        }
         return;
       }
       executeUpOrDown(lookup, true);

platform/platform-resources-en/src/messages/ActionsBundle.properties

@@ -82,6 +82,8 @@ action.EditorLeftWithSelection.text=Left with Selection
 action.EditorRightWithSelection.text=Right with Selection
 action.EditorLookupUp.text=Lookup Up
 action.EditorLookupDown.text=Lookup Down
+action.EditorLookupSelectionUp.text=Select Previous Completion Option 
+action.EditorLookupSelectionDown.text=Select Next Completion Option
 action.EditorIndentSelection.text=Indent Selection
 action.EditorUnindentSelection.text=Unindent Line or Selection
 action.EditorIndentLineOrSelection.text=Indent Line or Selection

platform/platform-resources/src/idea/PlatformLangActionManager.xml

@@ -23,6 +23,8 @@
 
     <action id="EditorLookupUp" class="com.intellij.codeInsight.lookup.impl.LookupActionHandler$UpAction"/>
     <action id="EditorLookupDown" class="com.intellij.codeInsight.lookup.impl.LookupActionHandler$DownAction"/>
+    <action id="EditorLookupSelectionUp" class="com.intellij.codeInsight.lookup.impl.LookupActionHandler$UpInLookupAction"/>
+    <action id="EditorLookupSelectionDown" class="com.intellij.codeInsight.lookup.impl.LookupActionHandler$DownInLookupAction"/>
   </actions>
 
   <xi:include href="/idea/PlatformActions.xml" xpointer="xpointer(/idea-plugin/*)"/>