From 87568772f469b6fd77f21b66549dd68a4e3689fe Mon Sep 17 00:00:00 2001
From: peter <peter@jetbrains.com>
Date: Mon, 7 Feb 2011 14:17:56 +0100
Subject: [PATCH] detailed diagnostics why a dom element is invalid

---
 .../CollectionElementInvocationHandler.java   | 13 ++++-
 .../util/xml/impl/DomFileElementImpl.java     | 14 ++++-
 .../intellij/util/xml/impl/DomImplUtil.java   | 19 ++++++
 .../util/xml/impl/DomInvocationHandler.java   | 58 ++++++++++++-------
 .../util/xml/impl/DomParentStrategy.java      |  3 +-
 .../xml/impl/DomRootInvocationHandler.java    | 13 +++--
 .../xml/impl/FixedChildDescriptionImpl.java   |  2 +-
 .../GetCompositeCollectionInvocation.java     |  2 +-
 .../xml/impl/GetFixedChildInvocation.java     |  2 +-
 .../intellij/util/xml/impl/GetInvocation.java |  3 +-
 .../xml/impl/PhysicalDomParentStrategy.java   |  4 +-
 .../util/xml/impl/RootDomParentStrategy.java  |  5 +-
 .../intellij/util/xml/impl/SetInvocation.java |  2 +-
 .../xml/impl/VirtualDomParentStrategy.java    |  8 ++-
 14 files changed, 107 insertions(+), 41 deletions(-)

diff --git a/xml/dom-impl/src/com/intellij/util/xml/impl/CollectionElementInvocationHandler.java b/xml/dom-impl/src/com/intellij/util/xml/impl/CollectionElementInvocationHandler.java
index 13dbcb3d300e..98d9712ea422 100644
--- a/xml/dom-impl/src/com/intellij/util/xml/impl/CollectionElementInvocationHandler.java
+++ b/xml/dom-impl/src/com/intellij/util/xml/impl/CollectionElementInvocationHandler.java
@@ -36,8 +36,17 @@ public class CollectionElementInvocationHandler extends DomInvocationHandler<Abs
   }
 
   @Override
-  public boolean isValid() {
-    return super.isValid() && getXmlTag() != null;
+  protected String checkValidity() {
+    final String s = super.checkValidity();
+    if (s != null) {
+      return s;
+    }
+
+    if (getXmlTag() == null) {
+      return "no XmlTag for collection element: " + getDomElementType();
+    }
+
+    return null;
   }
 
   public final void undefineInternal() {
diff --git a/xml/dom-impl/src/com/intellij/util/xml/impl/DomFileElementImpl.java b/xml/dom-impl/src/com/intellij/util/xml/impl/DomFileElementImpl.java
index 37718aff7a19..3c580052ddd9 100644
--- a/xml/dom-impl/src/com/intellij/util/xml/impl/DomFileElementImpl.java
+++ b/xml/dom-impl/src/com/intellij/util/xml/impl/DomFileElementImpl.java
@@ -329,7 +329,19 @@ public class DomFileElementImpl<T extends DomElement> implements DomFileElement<
   }
 
   public final boolean isValid() {
-    return myFile.isValid() && equals(myManager.getFileElement(myFile));
+    return checkValidity() == null;
+  }
+
+  @Nullable
+  public String checkValidity() {
+    if (!myFile.isValid()) {
+      return "Invalid file";
+    }
+    final DomFileElementImpl<DomElement> fileElement = myManager.getFileElement(myFile);
+    if (!equals(fileElement)) {
+      return "file element changed: " + fileElement;
+    }
+    return null;
   }
 
   @NotNull
diff --git a/xml/dom-impl/src/com/intellij/util/xml/impl/DomImplUtil.java b/xml/dom-impl/src/com/intellij/util/xml/impl/DomImplUtil.java
index 923a1f26e8c6..d661a720598c 100644
--- a/xml/dom-impl/src/com/intellij/util/xml/impl/DomImplUtil.java
+++ b/xml/dom-impl/src/com/intellij/util/xml/impl/DomImplUtil.java
@@ -47,6 +47,25 @@ public class DomImplUtil {
   private DomImplUtil() {
   }
 
+  public static void assertValidity(DomElement element, String msg) {
+    if (element instanceof DomFileElementImpl) {
+      final String s = ((DomFileElementImpl)element).checkValidity();
+      if (s != null) {
+        throw new AssertionError(s);
+      }
+      return;
+    }
+
+    final DomInvocationHandler handler = DomManagerImpl.getDomInvocationHandler(element);
+    assert handler != null;
+    try {
+      handler.assertValid();
+    }
+    catch (AssertionError e) {
+      throw new AssertionError(msg + e.getMessage());
+    }
+  }
+
   public static boolean isTagValueGetter(final JavaMethod method) {
     if (!isGetter(method)) {
       return false;
diff --git a/xml/dom-impl/src/com/intellij/util/xml/impl/DomInvocationHandler.java b/xml/dom-impl/src/com/intellij/util/xml/impl/DomInvocationHandler.java
index 27f90f69d9eb..860cd7d90748 100644
--- a/xml/dom-impl/src/com/intellij/util/xml/impl/DomInvocationHandler.java
+++ b/xml/dom-impl/src/com/intellij/util/xml/impl/DomInvocationHandler.java
@@ -135,15 +135,16 @@ public abstract class DomInvocationHandler<T extends AbstractDomChildDescription
 
   @Nullable
   public DomElement getParent() {
-    checkIsValid();
+    assertValid();
 
     final DomInvocationHandler handler = getParentHandler();
     return handler == null ? null : handler.getProxy();
   }
 
-  protected final void checkIsValid() {
-    if (!isValid()) {
-      LOG.error(myType.toString() + " @" + hashCode() + "\nclass=" + getClass() + "\nxml=" + getXmlElement());
+  protected final void assertValid() {
+    final String s = checkValidity();
+    if (s != null) {
+      throw new AssertionError(myType.toString() + " @" + hashCode() + "\nclass=" + getClass() + "\nxml=" + getXmlElement() + "; " + s);
     }
   }
 
@@ -271,7 +272,7 @@ public abstract class DomInvocationHandler<T extends AbstractDomChildDescription
   }
 
   public XmlTag ensureTagExists() {
-    checkIsValid();
+    assertValid();
 
     XmlTag tag = getXmlTag();
     if (tag != null) return tag;
@@ -315,35 +316,50 @@ public abstract class DomInvocationHandler<T extends AbstractDomChildDescription
     return getXmlTag().createChildTag(localName, tagName.getNamespace(element, getFile()), null, false);
   }
 
-  public boolean isValid() {
+  public final boolean isValid() {
+    return checkValidity() == null;
+  }
+
+  @Nullable
+  protected String checkValidity() {
     ProgressManager.checkCanceled();
     final DomParentStrategy parentStrategy = getParentStrategy();
-    if (!parentStrategy.isValid()) {
-      return false;
+    String error = parentStrategy.checkValidity();
+    if (error != null) {
+      return "Strategy: " + error;
     }
 
-    if (myLastModCount == myManager.getPsiModificationCount()) {
-      return true;
+    final long modCount = myManager.getPsiModificationCount();
+    if (myLastModCount == modCount) {
+      return null;
     }
 
     final XmlElement xmlElement = parentStrategy.getXmlElement();
     if (xmlElement != null) {
       final SemService semService = SemService.getSemService(myManager.getProject());
-      return rememberValidity(equals(semService.getSemElement(DomManagerImpl.DOM_HANDLER_KEY, xmlElement)));
+      final DomInvocationHandler actual = semService.getSemElement(DomManagerImpl.DOM_HANDLER_KEY, xmlElement);
+      if (!equals(actual)) {
+        return "element changed: " + this + "!=" + actual;
+      }
+      myLastModCount = modCount;
+      return null;
     }
 
     final DomInvocationHandler parent = getParentHandler();
-    return rememberValidity(parent != null && parent.isValid());
-  }
-
-
-  private boolean rememberValidity(boolean isValid) {
-    if (isValid) {
-      myLastModCount = myManager.getPsiModificationCount();
+    if (parent == null) {
+      return "no parent: " + getDomElementType();
     }
-    return isValid;
+
+    error = parent.checkValidity();
+    if (error != null) {
+      return "parent: " + error;
+    }
+
+    myLastModCount = modCount;
+    return null;
   }
 
+
   @NotNull
   public final DomGenericInfoEx getGenericInfo() {
     return myGenericInfo;
@@ -576,7 +592,7 @@ public abstract class DomInvocationHandler<T extends AbstractDomChildDescription
 
   @NotNull
   final AttributeChildInvocationHandler getAttributeChild(final AttributeChildDescriptionImpl description) {
-     checkIsValid();
+     assertValid();
     final EvaluatedXmlName evaluatedXmlName = createEvaluatedXmlName(description.getXmlName());
     final XmlTag tag = getXmlTag();
     
@@ -732,7 +748,7 @@ public abstract class DomInvocationHandler<T extends AbstractDomChildDescription
     XmlTag tag = getXmlTag();
     if (tag == null) return Collections.emptyList();
 
-    checkIsValid();
+    assertValid();
     final List<XmlTag> subTags = tagsGetter.fun(this);
     if (subTags.isEmpty()) return Collections.emptyList();
 
diff --git a/xml/dom-impl/src/com/intellij/util/xml/impl/DomParentStrategy.java b/xml/dom-impl/src/com/intellij/util/xml/impl/DomParentStrategy.java
index dbec29a6db8e..7fb7463c711f 100644
--- a/xml/dom-impl/src/com/intellij/util/xml/impl/DomParentStrategy.java
+++ b/xml/dom-impl/src/com/intellij/util/xml/impl/DomParentStrategy.java
@@ -34,5 +34,6 @@ public interface DomParentStrategy {
 
   @NotNull DomParentStrategy clearXmlElement();
 
-  boolean isValid();
+  @Nullable
+  String checkValidity();
 }
diff --git a/xml/dom-impl/src/com/intellij/util/xml/impl/DomRootInvocationHandler.java b/xml/dom-impl/src/com/intellij/util/xml/impl/DomRootInvocationHandler.java
index 16b62e2d7f4a..9b57cfa8147f 100644
--- a/xml/dom-impl/src/com/intellij/util/xml/impl/DomRootInvocationHandler.java
+++ b/xml/dom-impl/src/com/intellij/util/xml/impl/DomRootInvocationHandler.java
@@ -76,18 +76,23 @@ public class DomRootInvocationHandler extends DomInvocationHandler<AbstractDomCh
   }
 
   @Override
-  public boolean isValid() {
+  protected String checkValidity() {
     final XmlTag tag = (XmlTag)getXmlElement();
     if (tag != null && !tag.isValid()) {
-      return false;
+      return "invalid root tag";
     }
 
-    return myParent.isValid();
+    final String s = myParent.checkValidity();
+    if (s != null) {
+      return "root: " + s;
+    }
+
+    return null;
   }
 
   @NotNull
   public DomFileElementImpl getParent() {
-    checkIsValid();
+    assertValid();
     return myParent;
   }
 
diff --git a/xml/dom-impl/src/com/intellij/util/xml/impl/FixedChildDescriptionImpl.java b/xml/dom-impl/src/com/intellij/util/xml/impl/FixedChildDescriptionImpl.java
index 8fe2d86da405..84d450c6f223 100644
--- a/xml/dom-impl/src/com/intellij/util/xml/impl/FixedChildDescriptionImpl.java
+++ b/xml/dom-impl/src/com/intellij/util/xml/impl/FixedChildDescriptionImpl.java
@@ -69,7 +69,7 @@ public class FixedChildDescriptionImpl extends DomChildDescriptionImpl implement
     final List<DomElement> result = new SmartList<DomElement>();
     final DomInvocationHandler handler = DomManagerImpl.getDomInvocationHandler(element);
     if (handler != null) {
-      handler.checkIsValid();
+      handler.assertValid();
       for (int i = 0; i < myCount; i++) {
         result.add(handler.getFixedChild(Pair.create(this, i)).getProxy());
       }
diff --git a/xml/dom-impl/src/com/intellij/util/xml/impl/GetCompositeCollectionInvocation.java b/xml/dom-impl/src/com/intellij/util/xml/impl/GetCompositeCollectionInvocation.java
index 9e2c6ca67a6d..b4457905f8c6 100644
--- a/xml/dom-impl/src/com/intellij/util/xml/impl/GetCompositeCollectionInvocation.java
+++ b/xml/dom-impl/src/com/intellij/util/xml/impl/GetCompositeCollectionInvocation.java
@@ -33,7 +33,7 @@ class GetCompositeCollectionInvocation implements Invocation {
   }
 
   public Object invoke(final DomInvocationHandler<?> handler, final Object[] args) throws Throwable {
-    handler.checkIsValid();
+    handler.assertValid();
     Map<XmlTag,DomElement> map = new THashMap<XmlTag, DomElement>();
     for (final CollectionChildDescriptionImpl qname : myQnames) {
       for (DomElement element : handler.getCollectionChildren(qname, qname.getTagsGetter())) {
diff --git a/xml/dom-impl/src/com/intellij/util/xml/impl/GetFixedChildInvocation.java b/xml/dom-impl/src/com/intellij/util/xml/impl/GetFixedChildInvocation.java
index d3e1ad7f6b1a..82cce2c18577 100644
--- a/xml/dom-impl/src/com/intellij/util/xml/impl/GetFixedChildInvocation.java
+++ b/xml/dom-impl/src/com/intellij/util/xml/impl/GetFixedChildInvocation.java
@@ -16,7 +16,7 @@ public class GetFixedChildInvocation implements Invocation {
   }
 
   public Object invoke(final DomInvocationHandler<?> handler, final Object[] args) throws Throwable {
-    handler.checkIsValid();
+    handler.assertValid();
     return handler.getFixedChild(myPair).getProxy();
   }
 }
diff --git a/xml/dom-impl/src/com/intellij/util/xml/impl/GetInvocation.java b/xml/dom-impl/src/com/intellij/util/xml/impl/GetInvocation.java
index 4d82880a67ce..7f58cef4c1f5 100644
--- a/xml/dom-impl/src/com/intellij/util/xml/impl/GetInvocation.java
+++ b/xml/dom-impl/src/com/intellij/util/xml/impl/GetInvocation.java
@@ -7,7 +7,6 @@ import com.intellij.openapi.project.Project;
 import com.intellij.openapi.roots.ProjectRootManager;
 import com.intellij.openapi.util.Key;
 import com.intellij.openapi.util.Pair;
-import com.intellij.psi.PsiManager;
 import com.intellij.psi.util.CachedValue;
 import com.intellij.psi.util.CachedValueProvider;
 import com.intellij.psi.util.CachedValuesManager;
@@ -34,7 +33,7 @@ public class GetInvocation implements Invocation {
   }
 
   public Object invoke(final DomInvocationHandler<?> handler, final Object[] args) throws Throwable {
-    handler.checkIsValid();
+    handler.assertValid();
     if (myConverter == Converter.EMPTY_CONVERTER) {
       return getValueInner(handler, myConverter);
     }
diff --git a/xml/dom-impl/src/com/intellij/util/xml/impl/PhysicalDomParentStrategy.java b/xml/dom-impl/src/com/intellij/util/xml/impl/PhysicalDomParentStrategy.java
index 31951e84cf80..db329be62594 100644
--- a/xml/dom-impl/src/com/intellij/util/xml/impl/PhysicalDomParentStrategy.java
+++ b/xml/dom-impl/src/com/intellij/util/xml/impl/PhysicalDomParentStrategy.java
@@ -73,8 +73,8 @@ public class PhysicalDomParentStrategy implements DomParentStrategy {
     return new VirtualDomParentStrategy(parent);
   }
 
-  public boolean isValid() {
-    return myElement.isValid();
+  public String checkValidity() {
+    return myElement.isValid() ? null : "Invalid PSI";
   }
 
   public boolean equals(final Object o) {
diff --git a/xml/dom-impl/src/com/intellij/util/xml/impl/RootDomParentStrategy.java b/xml/dom-impl/src/com/intellij/util/xml/impl/RootDomParentStrategy.java
index cfd80b50499d..4e9daa90c496 100644
--- a/xml/dom-impl/src/com/intellij/util/xml/impl/RootDomParentStrategy.java
+++ b/xml/dom-impl/src/com/intellij/util/xml/impl/RootDomParentStrategy.java
@@ -53,8 +53,9 @@ public class RootDomParentStrategy implements DomParentStrategy {
     return this;
   }
 
-  public boolean isValid() {
-    return myFileElement.isValid();
+  @Override
+  public String checkValidity() {
+    return myFileElement.checkValidity();
   }
 
   public boolean equals(final Object o) {
diff --git a/xml/dom-impl/src/com/intellij/util/xml/impl/SetInvocation.java b/xml/dom-impl/src/com/intellij/util/xml/impl/SetInvocation.java
index 78ff5ba07919..487df9a31fb4 100644
--- a/xml/dom-impl/src/com/intellij/util/xml/impl/SetInvocation.java
+++ b/xml/dom-impl/src/com/intellij/util/xml/impl/SetInvocation.java
@@ -17,7 +17,7 @@ public class SetInvocation implements Invocation {
   }
 
   public Object invoke(final DomInvocationHandler<?> handler, final Object[] args) throws Throwable {
-    handler.checkIsValid();
+    handler.assertValid();
     final SubTag annotation = handler.getAnnotation(SubTag.class);
     final Object arg = args[0];
     if (annotation != null && annotation.indicator() && arg instanceof Boolean) {
diff --git a/xml/dom-impl/src/com/intellij/util/xml/impl/VirtualDomParentStrategy.java b/xml/dom-impl/src/com/intellij/util/xml/impl/VirtualDomParentStrategy.java
index a2dc0d6f8257..ad7a3f9b2436 100644
--- a/xml/dom-impl/src/com/intellij/util/xml/impl/VirtualDomParentStrategy.java
+++ b/xml/dom-impl/src/com/intellij/util/xml/impl/VirtualDomParentStrategy.java
@@ -72,8 +72,12 @@ public class VirtualDomParentStrategy implements DomParentStrategy {
     return this;
   }
 
-  public synchronized boolean isValid() {
-    return getModCount() == myModCount;
+  @Override
+  public synchronized String checkValidity() {
+    if (getModCount() == myModCount) {
+      return null;
+    }
+    return "mod count changed";
   }
 
   public boolean equals(final Object o) {