assert in tests that just created PsiAnchors can always be restored back

fix java/drools case with classes physical for no good reason (EA-72352 - assert: SymbolCollectingProcessor$ResultWithContext.getElement)

java/java-impl/src/com/intellij/psi/impl/smartPointers/JavaAnchorProvider.java

@@ -26,7 +26,7 @@ import org.jetbrains.annotations.Nullable;
 public class JavaAnchorProvider extends SmartPointerAnchorProvider {
   @Override
   public PsiElement getAnchor(@NotNull PsiElement element) {
-    if (!element.getLanguage().isKindOf(JavaLanguage.INSTANCE)) {
+    if (!element.getLanguage().isKindOf(JavaLanguage.INSTANCE) || !element.isPhysical()) {
       return null;
     }
 

platform/core-impl/src/com/intellij/psi/PsiAnchor.java

@@ -19,6 +19,7 @@ package com.intellij.psi;
 import com.intellij.lang.ASTNode;
 import com.intellij.lang.Language;
 import com.intellij.openapi.application.ApplicationManager;
+import com.intellij.openapi.diagnostic.Logger;
 import com.intellij.openapi.editor.Document;
 import com.intellij.openapi.fileEditor.FileDocumentManager;
 import com.intellij.openapi.project.Project;
@@ -40,6 +41,7 @@ import com.intellij.psi.tree.IElementType;
 import com.intellij.psi.tree.IStubFileElementType;
 import com.intellij.psi.util.PsiModificationTracker;
 import com.intellij.psi.util.PsiTreeUtil;
+import com.intellij.psi.util.PsiUtilCore;
 import org.jetbrains.annotations.NonNls;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
@@ -51,6 +53,7 @@ import java.util.Set;
  * @author db
  */
 public abstract class PsiAnchor {
+  private static final Logger LOG = Logger.getInstance("#com.intellij.psi.PsiAnchor");
   @Nullable
   public abstract PsiElement retrieve();
   public abstract PsiFile getFile();
@@ -59,10 +62,17 @@ public abstract class PsiAnchor {
 
   @NotNull
   public static PsiAnchor create(@NotNull final PsiElement element) {
-    if (!element.isValid()) {
-      throw new PsiInvalidElementAccessException(element);
-    }
+    PsiUtilCore.ensureValid(element);
 
+    PsiAnchor anchor = doCreateAnchor(element);
+    if (ApplicationManager.getApplication().isUnitTestMode() && !element.equals(anchor.retrieve())) {
+      LOG.error("Cannot restore element " + element + " of " + element.getClass() + " from anchor " + anchor);
+    }
+    return anchor;
+  }
+
+  @NotNull
+  private static PsiAnchor doCreateAnchor(@NotNull PsiElement element) {
     if (element instanceof PsiFile) {
       VirtualFile virtualFile = ((PsiFile)element).getVirtualFile();
       if (virtualFile != null) return new PsiFileReference(virtualFile, (PsiFile)element);
@@ -83,7 +93,7 @@ public abstract class PsiAnchor {
     PsiAnchor stubRef = createStubReference(element, file);
     if (stubRef != null) return stubRef;
 
-    if (!element.isPhysical() && element instanceof PsiCompiledElement || element instanceof LightElement || element instanceof SyntheticElement) {
+    if (!element.isPhysical()) {
       return wrapperOrHardReference(element);
     }
 
@@ -102,7 +112,10 @@ public abstract class PsiAnchor {
       }
     }
 
-    if (lang == null) lang = element.getLanguage();
+    if (lang == null) {
+      return wrapperOrHardReference(element);
+    }
+
     return new TreeRangeReference(file, textRange.getStartOffset(), textRange.getEndOffset(), element.getClass(), lang, virtualFile);
   }
 
@@ -195,17 +208,8 @@ public abstract class PsiAnchor {
     public PsiElement retrieve() {
       PsiFile psiFile = getFile();
       if (psiFile == null || !psiFile.isValid()) return null;
-      PsiElement element = psiFile.getViewProvider().findElementAt(myStartOffset, myLanguage);
-      if (element == null) return null;
 
-      while  (!element.getClass().equals(myClass) ||
-              element.getTextRange().getStartOffset() != myStartOffset ||
-              element.getTextRange().getEndOffset() != myEndOffset) {
-        element = element.getParent();
-        if (element == null || element.getTextRange() == null) return null;
-      }
-
-      return element;
+      return SelfElementInfo.findElementInside(psiFile, myStartOffset, myEndOffset, myClass, myLanguage);
     }
 
     @Override

platform/core-impl/src/com/intellij/psi/impl/smartPointers/SelfElementInfo.java

@@ -126,7 +126,7 @@ public class SelfElementInfo extends SmartPointerElementInfo {
     return restoreFileFromVirtual(getVirtualFile(), getProject(), myLanguage);
   }
 
-  static PsiElement findElementInside(@NotNull PsiFile file,
+  public static PsiElement findElementInside(@NotNull PsiFile file,
                                       int syncStartOffset,
                                       int syncEndOffset,
                                       @NotNull Class type,