manage DummyHolder's tree in the same way as PsiFileImpl does (EA-96901 - assert: FileTrees.withGreenStub)

java/java-tests/testSrc/com/intellij/codeInspection/PurityInferenceFromSourceTest.groovy

@@ -213,6 +213,24 @@ public Foo() {
     """
   }
 
+  void "test delegate to a method calling local class constructor"() {
+    myFixture.addClass("""
+class Another { 
+  static Object method() {
+    class LocalClass {
+      LocalClass() { launchMissiles(); }
+    }
+    return new LocalClass();
+  } 
+}
+  """)
+    assertPure false, """
+    Object smth() {
+        return Another.method();
+    }
+    """
+  }
+
   private void assertPure(boolean expected, String classBody) {
     def clazz = myFixture.addClass("final class Foo { $classBody }")
     assert !((PsiFileImpl) clazz.containingFile).contentsLoaded

java/java-tests/testSrc/com/intellij/psi/StubAstSwitchTest.groovy

@@ -20,6 +20,8 @@ import com.intellij.openapi.application.ReadAction
 import com.intellij.openapi.command.WriteCommandAction
 import com.intellij.openapi.fileEditor.FileDocumentManager
 import com.intellij.openapi.vfs.VfsUtil
+import com.intellij.psi.impl.java.stubs.JavaStubElementTypes
+import com.intellij.psi.impl.source.DummyHolder
 import com.intellij.psi.impl.source.PsiClassImpl
 import com.intellij.psi.impl.source.PsiFileImpl
 import com.intellij.psi.impl.source.PsiJavaFileImpl
@@ -317,4 +319,14 @@ class B {
       }
     }
   }
+
+  void "test DummyHolder calcStubTree does not fail"() {
+    def text = "{ new Runnable() { public void run() {} }; }"
+    def file = JavaPsiFacade.getElementFactory(project).createCodeBlockFromText(text, null).containingFile
+
+    // main thing is it doesn't fail; DummyHolder.calcStubTree can be changed to null in future if we decide we don't need it
+    def stubTree = assertInstanceOf(file, DummyHolder).calcStubTree()
+
+    assert stubTree.plainList.find { it.stubType == JavaStubElementTypes.ANONYMOUS_CLASS }
+  }
 }

platform/core-impl/src/com/intellij/psi/impl/source/DummyHolder.java

@@ -34,7 +34,6 @@ public class DummyHolder extends PsiFileImpl {
   private final CharTable myTable;
   private final Boolean myExplicitlyValid;
   private final Language myLanguage;
-  private volatile FileElement myFileElement;
   @SuppressWarnings("EmptyClass") private static class DummyHolderTreeLock {}
   private final DummyHolderTreeLock myTreeElementLock = new DummyHolderTreeLock();
 
@@ -71,9 +70,9 @@ public class DummyHolder extends PsiFileImpl {
     myContext = context;
     myTable = table != null ? table : IdentityCharTable.INSTANCE;
     if (contentElement instanceof FileElement) {
-      myFileElement = (FileElement)contentElement;
-      myFileElement.setPsi(this);
-      myFileElement.setCharTable(myTable);
+      ((FileElement)contentElement).setPsi(this);
+      ((FileElement)contentElement).setCharTable(myTable);
+      setTreeElementPointer((FileElement)contentElement);
     }
     else if (contentElement != null) {
       getTreeElement().rawAddChildren(contentElement);
@@ -130,16 +129,16 @@ public class DummyHolder extends PsiFileImpl {
   @Override
   @NotNull
   public FileElement getTreeElement() {
-    FileElement fileElement = myFileElement;
+    FileElement fileElement = super.derefTreeElement();
     if (fileElement != null) return fileElement;
 
     synchronized (myTreeElementLock) {
-      fileElement = myFileElement;
+      fileElement = super.derefTreeElement();
       if (fileElement == null) {
         fileElement = new FileElement(TokenType.DUMMY_HOLDER, null);
         fileElement.setPsi(this);
         if (myTable != null) fileElement.setCharTable(myTable);
-        myFileElement = fileElement;
+        setTreeElementPointer(fileElement);
         clearCaches();
       }
       return fileElement;
@@ -155,7 +154,7 @@ public class DummyHolder extends PsiFileImpl {
   @Override
   @SuppressWarnings({"CloneDoesntDeclareCloneNotSupportedException"})
   protected PsiFileImpl clone() {
-    final PsiFileImpl psiClone = cloneImpl(myFileElement);
+    final PsiFileImpl psiClone = cloneImpl(getTreeElement());
     final DummyHolderViewProvider dummyHolderViewProvider = new DummyHolderViewProvider(getManager());
     myViewProvider = dummyHolderViewProvider;
     dummyHolderViewProvider.setDummyHolder((DummyHolder)psiClone);

platform/core-impl/src/com/intellij/psi/impl/source/PsiFileImpl.java

@@ -131,7 +131,7 @@ public abstract class PsiFileImpl extends ElementBase implements PsiFileEx, PsiF
     return null;
   }
 
-  private FileElement derefTreeElement() {
+  protected FileElement derefTreeElement() {
     return myTrees.derefTreeElement();
   }