assert file & document validity on getText (EA-75987 - assert: ShredImpl.<init>)

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

@@ -613,6 +613,10 @@ public abstract class PsiDocumentManagerBase extends PsiDocumentManager implemen
       Document delegate = window.getDelegate();
       if (delegate instanceof FrozenDocument) return (DocumentEx)window;
 
+      if (!window.isValid()) {
+        throw new AssertionError("host committed: " + isCommitted(delegate) + ", window=" + window);
+      }
+
       UncommittedInfo info = myUncommittedInfos.get(delegate);
       DocumentWindow answer = info == null ? null : info.myFrozenWindows.get(document);
       if (answer == null) answer = freezeWindow(window);

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

@@ -47,6 +47,7 @@ import com.intellij.psi.search.PsiElementProcessor;
 import com.intellij.psi.search.SearchScope;
 import com.intellij.psi.stubs.*;
 import com.intellij.psi.tree.*;
+import com.intellij.psi.util.PsiUtilCore;
 import com.intellij.reference.SoftReference;
 import com.intellij.util.FileContentUtilCore;
 import com.intellij.util.IncorrectOperationException;
@@ -385,6 +386,10 @@ public abstract class PsiFileImpl extends ElementBase implements PsiFileEx, PsiF
 
   @Override
   public String getText() {
+    final ASTNode tree = derefTreeElement();
+    if (tree != null) return tree.getText();
+
+    PsiUtilCore.ensureValid(this);
     return getViewProvider().getContents().toString();
   }
 
@@ -393,6 +398,7 @@ public abstract class PsiFileImpl extends ElementBase implements PsiFileEx, PsiF
     final ASTNode tree = derefTreeElement();
     if (tree != null) return tree.getTextLength();
 
+    PsiUtilCore.ensureValid(this);
     return getViewProvider().getContents().length();
   }