PY-64402: WIP: Make an "Other" group collapsed.

Such groups are rendered as plain text until a user clicks on them. After that, they are substituted with children.

Since there's been no such API in the platform, I've introduced `com.intellij.openapi.wm.impl.welcomeScreen.collapsedActionGroup` which works along with `ActionGroupPanelWrapper` for project types in "New project wizard".

It is now only used by Python, see `PycharmNewProjectStep`

GitOrigin-RevId: f38a0643ce6bc65e5e2f6485ef255ee20ba2e7a5

platform/platform-impl/src/com/intellij/openapi/wm/impl/welcomeScreen/ActionGroupPanelWrapper.java

@@ -12,6 +12,9 @@ import com.intellij.openapi.util.*;
 import com.intellij.openapi.util.text.StringUtil;
 import com.intellij.openapi.wm.IdeFocusManager;
 import com.intellij.openapi.wm.WindowManager;
+import com.intellij.openapi.wm.impl.welcomeScreen.collapsedActionGroup.CollapsedActionGroup;
+import com.intellij.openapi.wm.impl.welcomeScreen.collapsedActionGroup.CollapsedButtonKt;
+import com.intellij.openapi.wm.impl.welcomeScreen.collapsedActionGroup.ListListenerCollapsedActionGroupExpander;
 import com.intellij.ui.*;
 import com.intellij.ui.components.JBList;
 import com.intellij.ui.components.panels.NonOpaquePanel;
@@ -46,6 +49,7 @@ public final class ActionGroupPanelWrapper {
     java.util.List<AnAction> groups = flattenActionGroups(action);
     DefaultListModel<AnAction> model = JBList.createDefaultListModel(groups);
     JBList<AnAction> list = new JBList<>(model);
+    ListListenerCollapsedActionGroupExpander.expandCollapsableGroupsOnSelection(list, model, parentDisposable);
     for (AnAction group : groups) {
       if (group instanceof Disposable) {
         Disposer.register(parentDisposable, (Disposable)group);
@@ -94,8 +98,31 @@ public final class ActionGroupPanelWrapper {
                              return getProjectsBackground();
                            }
 
+                           @Override
+                           public Component getListCellRendererComponent(JList<? extends AnAction> list,
+                                                                         AnAction value,
+                                                                         int index,
+                                                                         boolean isSelected,
+                                                                         boolean cellHasFocus) {
+                             var component = super.getListCellRendererComponent(list, value, index, isSelected, cellHasFocus);
+                             // Collapsable group should be rendered as collapsable button
+                             if (value instanceof CollapsedActionGroup actionGroup) {
+                               return CollapsedButtonKt.createCollapsedButton(actionGroup, childAction -> {
+                                 // To get an action width we set to the component, render it, and see component width
+                                 // This approach obeys component spacing, font's size e.t.c
+                                 setLabelByAction(childAction);
+                                 return component.getPreferredSize().width;
+                               });
+                             }
+                             return component;
+                           }
+
                            @Override
                            protected void customizeComponent(JList<? extends AnAction> list, AnAction value, boolean isSelected) {
+                             setLabelByAction(value);
+                           }
+
+                           private void setLabelByAction(@NotNull AnAction value) {
                              if (myTextLabel != null) {
                                myTextLabel.setText(value.getTemplateText());
                                myTextLabel.setIcon(value.getTemplatePresentation().getIcon());
@@ -249,24 +276,41 @@ public final class ActionGroupPanelWrapper {
 
   private static List<AnAction> flattenActionGroups(final @NotNull ActionGroup action) {
     final ArrayList<AnAction> groups = new ArrayList<>();
-    String groupName;
     for (AnAction anAction : action.getChildren(null)) {
-      if (anAction instanceof ActionGroup) {
-        groupName = anAction.getTemplateText();
-        for (AnAction childAction : ((ActionGroup)anAction).getChildren(null)) {
-          if (groupName != null) {
-            setParentGroupName(groupName, childAction);
-          }
-          groups.add(childAction);
+      if (anAction instanceof ActionGroup actionGroup) {
+        var elementsToAdd = getActionChildrenToAddInsteadOfAction(actionGroup);
+        if (elementsToAdd != null) {
+          // Some GroupActions shouldn't be added directly, but children must be added instead
+          groups.addAll(Arrays.asList(elementsToAdd));
+          continue;
         }
       }
-      else {
-        groups.add(anAction);
-      }
+      // Collapse groups and regular actions
+      groups.add(anAction);
     }
     return groups;
   }
 
+  /**
+   * Action children must have parent name to display group separator.
+   * {@link CollapsedActionGroup} will be substituted with children later, when clicked.
+   * Regular {@link ActionGroup} must be replaced now
+   */
+  @NotNull
+  private static AnAction @Nullable [] getActionChildrenToAddInsteadOfAction(@NotNull ActionGroup actionGroup) {
+    String groupName;
+    AnAction[] children = actionGroup.getChildren(null);
+    groupName = actionGroup.getTemplateText();
+    for (AnAction childAction : children) {
+      if (groupName != null) {
+        setParentGroupName(groupName, childAction);
+      }
+    }
+    return actionGroup instanceof CollapsedActionGroup
+           ? null
+           : children;
+  }
+
   private static @NlsContexts.Separator String getParentGroupName(final @NotNull AnAction value) {
     return (String)value.getTemplatePresentation().getClientProperty(ACTION_GROUP_KEY);
   }

platform/platform-impl/src/com/intellij/openapi/wm/impl/welcomeScreen/collapsedActionGroup/CollapsedActionGroup.kt

@@ -0,0 +1,13 @@
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
+package com.intellij.openapi.wm.impl.welcomeScreen.collapsedActionGroup
+
+import com.intellij.openapi.actionSystem.AnAction
+import com.intellij.openapi.actionSystem.DefaultActionGroup
+import org.jetbrains.annotations.Nls
+
+/**
+ * As [com.intellij.openapi.actionSystem.ActionGroup] it might contain children [AnAction], but children
+ * aren't displayed until user clicks on it.
+ * this logic is part  [com.intellij.openapi.wm.impl.welcomeScreen.ActionGroupPanelWrapper]
+ */
+class CollapsedActionGroup(name: @Nls String, actions: List<AnAction>) : DefaultActionGroup(name, actions)

platform/platform-impl/src/com/intellij/openapi/wm/impl/welcomeScreen/collapsedActionGroup/CollapsedButton.kt

@@ -0,0 +1,31 @@
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
+package com.intellij.openapi.wm.impl.welcomeScreen.collapsedActionGroup
+
+import com.intellij.openapi.actionSystem.AnAction
+import com.intellij.openapi.util.NlsContexts
+import com.intellij.ui.dsl.builder.panel
+import com.intellij.util.concurrency.annotations.RequiresEdt
+import java.awt.Dimension
+import javax.swing.JComponent
+
+/**
+ * Crates [JComponent] that renders as collapsed button with text from [actionGroup] and width from the longest child action.
+ */
+@RequiresEdt
+fun createCollapsedButton(actionGroup: CollapsedActionGroup, getActionWidth: (childAction: AnAction) -> Int): JComponent {
+  val button = collapsedButton(actionGroup.templateText)
+
+  val maxChildWidth = actionGroup.getChildren(null).maxOfOrNull { getActionWidth(it) }
+  val preferredSize = button.preferredSize
+  if (maxChildWidth != null && maxChildWidth > preferredSize.width) {
+    button.preferredSize = Dimension(maxChildWidth, button.preferredSize.height)
+  }
+  return button
+}
+
+@RequiresEdt
+private fun collapsedButton(@NlsContexts.BorderTitle text: String) = panel {
+  collapsibleGroup(text) {
+
+  }
+}

platform/platform-impl/src/com/intellij/openapi/wm/impl/welcomeScreen/collapsedActionGroup/ListListenerCollapsedActionGroupExpander.kt

@@ -0,0 +1,38 @@
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
+package com.intellij.openapi.wm.impl.welcomeScreen.collapsedActionGroup
+
+import com.intellij.openapi.Disposable
+import com.intellij.openapi.actionSystem.AnAction
+import com.intellij.openapi.util.Disposer
+import com.intellij.util.concurrency.annotations.RequiresEdt
+import javax.swing.DefaultListModel
+import javax.swing.JList
+import javax.swing.event.ListSelectionEvent
+import javax.swing.event.ListSelectionListener
+
+/**
+ * Listens for [JList] selection events, and when [CollapsedActionGroup] selected -- substitutes it with children
+ * See [expandCollapsableGroupsOnSelection]
+ */
+class ListListenerCollapsedActionGroupExpander private constructor(
+  private val list: JList<AnAction>,
+  private val model: DefaultListModel<AnAction>) : ListSelectionListener {
+  companion object {
+    @JvmStatic
+    @RequiresEdt
+    fun expandCollapsableGroupsOnSelection(list: JList<AnAction>, model: DefaultListModel<AnAction>, parentDisposable: Disposable) {
+      val instance = ListListenerCollapsedActionGroupExpander(list, model)
+      list.addListSelectionListener(instance)
+      Disposer.register(parentDisposable, Disposable { list.removeListSelectionListener(instance) })
+    }
+  }
+
+  override fun valueChanged(e: ListSelectionEvent) {
+    // Replace collapsable action with children
+    val selectedIndex = list.selectedIndex
+    val group = list.selectedValue as? CollapsedActionGroup ?: return
+    model.remove(selectedIndex)
+    model.addAll(selectedIndex, group.getChildren(null).asList())
+    list.removeListSelectionListener(this)
+  }
+}

platform/platform-impl/src/com/intellij/openapi/wm/impl/welcomeScreen/collapsedActionGroup/package-info.java

@@ -0,0 +1,7 @@
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
+/**
+ * {@link com.intellij.openapi.wm.impl.welcomeScreen.collapsedActionGroup.CollapsedActionGroup} is
+ * used by {@link com.intellij.openapi.wm.impl.welcomeScreen.ActionGroupPanelWrapper}.
+ * Such groups rendered as items which are substituted by children on click.
+ */
+package com.intellij.openapi.wm.impl.welcomeScreen.collapsedActionGroup;

platform/platform-tests/testSrc/com/intellij/openapi/ui/CollapsedActionGroupTest.kt

@@ -0,0 +1,67 @@
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
+package com.intellij.openapi.ui
+
+import com.intellij.openapi.Disposable
+import com.intellij.openapi.actionSystem.AnAction
+import com.intellij.openapi.actionSystem.AnActionEvent
+import com.intellij.openapi.wm.impl.welcomeScreen.collapsedActionGroup.CollapsedActionGroup
+import com.intellij.openapi.wm.impl.welcomeScreen.collapsedActionGroup.ListListenerCollapsedActionGroupExpander
+import com.intellij.openapi.wm.impl.welcomeScreen.collapsedActionGroup.createCollapsedButton
+import com.intellij.testFramework.junit5.RunInEdt
+import com.intellij.testFramework.junit5.TestApplication
+import com.intellij.testFramework.junit5.TestDisposable
+import org.hamcrest.MatcherAssert
+import org.hamcrest.Matchers
+import org.junit.jupiter.api.Test
+import javax.swing.DefaultListModel
+import javax.swing.JList
+
+@TestApplication
+@RunInEdt
+class CollapsedActionGroupTest {
+  @TestDisposable
+  private lateinit var disposable: Disposable
+
+  private val actionsBeforeCollapseGroup = (1..5).map { MyAction(it) }.toList()
+  private val subActions = (6..8).map { MyAction(it) }.toList()
+  private val actionsAfterCollapseGroup = (9..12).map { MyAction(it) }.toList()
+
+  private val collapseGroup = CollapsedActionGroup("MyGroup", subActions)
+
+  @Test
+  fun listenerOpensActions() {
+    val initialModelList = actionsBeforeCollapseGroup + listOf(collapseGroup) + actionsAfterCollapseGroup
+    val model = DefaultListModel<AnAction>().apply {
+      addAll(initialModelList)
+    }
+    val list = JList(model)
+    ListListenerCollapsedActionGroupExpander.expandCollapsableGroupsOnSelection(list, model, disposable)
+
+    list.selectedIndex = 1
+    MatcherAssert.assertThat("Model broken after selection", model.elements().toList(), Matchers.equalTo(initialModelList))
+
+    list.selectedIndex = initialModelList.size - 1
+    MatcherAssert.assertThat("Model broken after selection", model.elements().toList(), Matchers.equalTo(initialModelList))
+
+    list.selectedIndex = actionsBeforeCollapseGroup.size // Click on collapse grop
+    MatcherAssert.assertThat("Model hasn't been expanded after clicking on collapse button", model.elements().toList(), Matchers.equalTo(
+      actionsBeforeCollapseGroup + subActions + actionsAfterCollapseGroup
+    ))
+  }
+
+  @Test
+  fun collapsedButtonWidth() {
+    val componentWidth = createCollapsedButton(collapseGroup) {
+      (it as MyAction).preferedWidth
+    }.preferredSize.width
+    val maxActionWidth = subActions.maxOfOrNull { it.preferedWidth }!!
+    MatcherAssert.assertThat(
+      "Component size should be at least as wide as longest action not to blink when actions appear",
+      componentWidth, Matchers.greaterThanOrEqualTo(maxActionWidth))
+  }
+}
+
+private class MyAction(id: Int) : AnAction("Action$id") {
+  override fun actionPerformed(e: AnActionEvent) = Unit
+  val preferedWidth = id * 100
+}

python/ide/impl/src/com/intellij/pycharm/community/ide/impl/newProject/steps/PyCharmNewProjectStep.java

@@ -6,6 +6,7 @@ import com.intellij.ide.util.projectWizard.ProjectSettingsStepBase;
 import com.intellij.openapi.actionSystem.AnAction;
 import com.intellij.openapi.actionSystem.DefaultActionGroup;
 import com.intellij.openapi.util.Pair;
+import com.intellij.openapi.wm.impl.welcomeScreen.collapsedActionGroup.CollapsedActionGroup;
 import com.intellij.platform.DirectoryProjectGenerator;
 import com.intellij.util.ObjectUtils;
 import com.intellij.pycharm.community.ide.impl.PyCharmCommunityCustomizationBundle;
@@ -79,8 +80,8 @@ public final class PyCharmNewProjectStep extends AbstractNewProjectStep<PyNewPro
 
         var python = new DefaultActionGroup(PyCharmCommunityCustomizationBundle.message("new.project.python.group.name"),
                                             map.get(true).stream().flatMap(pair -> Arrays.stream(pair.second)).toList());
-        var other = new DefaultActionGroup(PyCharmCommunityCustomizationBundle.message("new.project.other.group.name"),
-                                          map.get(false).stream().flatMap(pair -> Arrays.stream(pair.second)).toList());
+        var other = new CollapsedActionGroup(PyCharmCommunityCustomizationBundle.message("new.project.other.group.name"),
+                                             map.get(false).stream().flatMap(pair -> Arrays.stream(pair.second)).toList());
         return new AnAction[] { python, other };
       }