DOM stubs: exclude some dom extenders from stub building

plugins/devkit/src/dom/IdeaPlugin.java

@@ -105,7 +105,6 @@ public interface IdeaPlugin extends DomElement {
 
   @NotNull
   @SubTagList("extensions")
-  @Stubbed
   List<Extensions> getExtensions();
   Extensions addExtensions();
 

plugins/devkit/src/dom/impl/ExtensionDomExtender.java

@@ -147,6 +147,11 @@ public class ExtensionDomExtender extends DomExtender<Extensions> {
     }
   }
 
+  @Override
+  public boolean supportsStubs() {
+    return false;
+  }
+
   private static Set<IdeaPlugin> getVisiblePlugins(IdeaPlugin ideaPlugin) {
     Set<IdeaPlugin> result = ContainerUtil.newHashSet();
     MultiMap<String, IdeaPlugin> byId = getPluginMap(ideaPlugin.getManager().getProject());

plugins/devkit/testSources/codeInsight/PluginXmlDomStubsTest.java

@@ -29,9 +29,6 @@ public class PluginXmlDomStubsTest extends DomStubTest {
                   "    Element:depends\n" +
                   "    Element:module\n" +
                   "      Attribute:value:myModule\n" +
-                  "    Element:extensions\n" +
-                  "      Attribute:xmlns:someNS\n" +
-                  "      Attribute:defaultExtensionNs:com.intellij\n" +
                   "    Element:extensionPoints\n" +
                   "      Element:extensionPoint\n" +
                   "        Attribute:name:myEP\n" +

xml/dom-impl/src/com/intellij/util/xml/reflect/DomExtenderEP.java

@@ -21,6 +21,7 @@ import com.intellij.openapi.extensions.ExtensionPointName;
 import com.intellij.openapi.project.Project;
 import com.intellij.util.xml.impl.DomInvocationHandler;
 import com.intellij.util.xmlb.annotations.Attribute;
+import com.intellij.xml.util.XmlUtil;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
@@ -53,6 +54,7 @@ public class DomExtenderEP extends AbstractExtensionPointBean {
       }
     }
     if (myDomClass.isAssignableFrom(handler.getRawType())) {
+      if (!myExtender.supportsStubs() && XmlUtil.isStubBuilding()) return registrar;
       if (registrar == null) {
         registrar = new DomExtensionsRegistrarImpl();
       }

xml/dom-openapi/src/com/intellij/util/xml/reflect/DomExtender.java

@@ -33,4 +33,12 @@ public abstract class DomExtender<T extends DomElement> {
    * @param registrar a place to register your own DOM children descriptions
    */
   public abstract void registerExtensions(@NotNull T t, @NotNull final DomExtensionsRegistrar registrar);
+
+  /**
+   * Makes stub building for extensions available.
+   * To be compatible with general stubs contract, extension should NOT depend on anything beyond current file's content.
+   */
+  public boolean supportsStubs() {
+    return true;
+  }
 }

xml/dom-tests/tests/com/intellij/util/xml/stubs/DomStubBuilderTest.java

@@ -106,5 +106,10 @@ public class DomStubBuilderTest extends DomStubTest {
     public void registerExtensions(@NotNull Bar bar, @NotNull DomExtensionsRegistrar registrar) {
       registrar.registerAttributeChildExtension(new XmlName("extend"), Custom.class);
     }
+
+    @Override
+    public boolean supportsStubs() {
+      return true;
+    }
   }
 }