AbstractNewProjectDialog refactoring:

All implementations use `AbstractNewProjectStep` and any other action wouldn't really work.

We deprecate old method and force users to use new (the one that returns `AbstractNewProjectStep`).

Some methods are finalized because overwriting them might break the contract


Merge-request: IJ-MR-142822
Merged-by: Ilya Kazakevich <ilya.kazakevich@jetbrains.com>

GitOrigin-RevId: aafa6fb336f78391077773ac6d202d35c15a8c8d

platform/lang-impl/api-dump-unreviewed.txt

@@ -18436,14 +18436,15 @@ a:com.intellij.ide.util.gotoByName.SimpleChooseByNameModel
 a:com.intellij.ide.util.projectWizard.AbstractNewProjectDialog
 - com.intellij.openapi.ui.DialogWrapper
 - <init>():V
-- p:createActions():javax.swing.Action[]
-- p:createCenterPanel():javax.swing.JComponent
-- pa:createRootStep():com.intellij.openapi.actionSystem.DefaultActionGroup
+- pf:createActions():javax.swing.Action[]
+- pf:createCenterPanel():javax.swing.JComponent
+- p:createNewProjectStep():com.intellij.ide.util.projectWizard.AbstractNewProjectStep
+- p:createRootStep():com.intellij.openapi.actionSystem.DefaultActionGroup
 - p:createSouthPanel():javax.swing.JComponent
 - p:getHelpId():java.lang.String
 - getPreferredFocusedComponent():javax.swing.JComponent
 - p:getStyle():com.intellij.openapi.ui.DialogWrapper$DialogStyle
-- p:init():V
+- pf:init():V
 a:com.intellij.ide.util.projectWizard.AbstractNewProjectStep
 - com.intellij.openapi.actionSystem.DefaultActionGroup
 - com.intellij.openapi.project.DumbAware

platform/lang-impl/src/com/intellij/ide/util/projectWizard/AbstractNewProjectDialog.java

@@ -1,6 +1,7 @@
 // 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.ide.util.projectWizard;
 
+import com.intellij.diagnostic.PluginException;
 import com.intellij.ide.wizard.Step;
 import com.intellij.ide.wizard.StepAdapter;
 import com.intellij.openapi.Disposable;
@@ -44,7 +45,7 @@ public abstract class AbstractNewProjectDialog extends DialogWrapper {
   }
 
   @Override
-  protected void init() {
+  protected final void init() {
     super.init();
     DialogWrapperPeer peer = getPeer();
     JRootPane pane = peer.getRootPane();
@@ -56,16 +57,14 @@ public abstract class AbstractNewProjectDialog extends DialogWrapper {
   }
 
   @Override
-  protected @Nullable JComponent createCenterPanel() {
+  protected final @Nullable JComponent createCenterPanel() {
     setTitle(AbstractNewProjectStep.EP_NAME.hasAnyExtensions() ? ProjectBundle.message("dialog.title.new.project")
-                                                                  : ProjectBundle.message("dialog.title.create.project"));
-    DefaultActionGroup root = createRootStep();
+                                                               : ProjectBundle.message("dialog.title.create.project"));
+    var root = createNewProjectStep();
     Disposer.register(getDisposable(), () -> root.removeAll());
 
     Pair<JPanel, JBList<AnAction>> pair = ActionGroupPanelWrapper.createActionGroupPanel(root, null, getDisposable());
-    if (root instanceof AbstractNewProjectStep<?> projectStep) {
-      projectStep.setWizardContext(createWizardContext(pair, getDisposable()));
-    }
+    root.setWizardContext(createWizardContext(pair, getDisposable()));
     JPanel component = pair.first;
     myPair = pair;
     UiNotifyConnector.doWhenFirstShown(myPair.second, () -> ScrollingUtil.ensureSelectionExists(myPair.second));
@@ -113,7 +112,24 @@ public abstract class AbstractNewProjectDialog extends DialogWrapper {
     return DialogStyle.COMPACT;
   }
 
-  protected abstract DefaultActionGroup createRootStep();
+  /**
+   * @deprecated use {@link #createNewProjectStep()}
+   */
+  @Deprecated
+  @Nullable
+  protected DefaultActionGroup createRootStep() {
+    return null;
+  }
+
+  @NotNull
+  protected AbstractNewProjectStep<?> createNewProjectStep() {
+    var step = createRootStep();
+    if (step instanceof AbstractNewProjectStep<?> abstractNewProjectStep) {
+      return abstractNewProjectStep;
+    }
+    throw PluginException.createByClass(new AssertionError("override 'createNewProjectStep' instead of deprecated 'createRootStep'"), getClass());
+  }
+
 
   @Override
   protected String getHelpId() {
@@ -121,12 +137,13 @@ public abstract class AbstractNewProjectDialog extends DialogWrapper {
   }
 
   @Override
-  protected Action @NotNull [] createActions() {
+  protected final Action @NotNull [] createActions() {
     return new Action[0];
   }
 
   static class ProjectStepPeerHolder extends StepAdapter {
     private final ProjectGeneratorPeer<?> myPeer;
+
     ProjectStepPeerHolder(ProjectGeneratorPeer<?> peer) {
       myPeer = peer;
     }

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

@@ -2,11 +2,13 @@
 package com.intellij.pycharm.community.ide.impl.newProject;
 
 import com.intellij.ide.util.projectWizard.AbstractNewProjectDialog;
+import com.intellij.ide.util.projectWizard.AbstractNewProjectStep;
 import com.intellij.pycharm.community.ide.impl.newProject.steps.PyCharmNewProjectStep;
+import org.jetbrains.annotations.NotNull;
 
 public class PyCharmNewProjectDialog extends AbstractNewProjectDialog {
   @Override
-  protected PyCharmNewProjectStep createRootStep() {
+  protected @NotNull AbstractNewProjectStep<?> createNewProjectStep() {
     return new PyCharmNewProjectStep();
   }