From e484284d3aafeea33aff7e6ef319ba9b474ee711 Mon Sep 17 00:00:00 2001
From: Andrey Vlasovskikh <andrey.vlasovskikh@jetbrains.com>
Date: Wed, 13 Feb 2013 21:23:21 +0400
Subject: [PATCH] Fixed PIEAE when imported file is renamed and then renamed
 back using undo

ExportedNameCache contains elements with parent file stubs without the PSI element
set. Therefore these elements are invalid. We reset exported name cache each time
the modification stamp differs from its value at the moment of cache creation,
---
 .../com/jetbrains/python/psi/impl/PyFileImpl.java  | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/python/src/com/jetbrains/python/psi/impl/PyFileImpl.java b/python/src/com/jetbrains/python/psi/impl/PyFileImpl.java
index 5408cd0b9aee..135000abe605 100644
--- a/python/src/com/jetbrains/python/psi/impl/PyFileImpl.java
+++ b/python/src/com/jetbrains/python/psi/impl/PyFileImpl.java
@@ -54,8 +54,10 @@ public class PyFileImpl extends PsiFileBase implements PyFile, PyExpression {
     private final List<PsiElement> myNameDefiners = new ArrayList<PsiElement>();
     private final List<String> myNameDefinerNegativeCache = new ArrayList<String>();
     private long myNameDefinerOOCBModCount = -1;
+    private final long myModificationStamp;
 
-    private ExportedNameCache() {
+    private ExportedNameCache(long modificationStamp) {
+      myModificationStamp = modificationStamp;
       final List<PsiElement> children = PyPsiUtils.collectAllStubChildren(PyFileImpl.this, getStub());
       final List<PyExceptPart> exceptParts = new ArrayList<PyExceptPart>();
       for (PsiElement child : children) {
@@ -226,6 +228,9 @@ public class PyFileImpl extends PsiFileBase implements PyFile, PyExpression {
       return null;
     }
 
+    public long getModificationStamp() {
+      return myModificationStamp;
+    }
   }
 
   public PyFileImpl(FileViewProvider viewProvider) {
@@ -433,8 +438,13 @@ public class PyFileImpl extends PsiFileBase implements PyFile, PyExpression {
     ExportedNameCache cache;
     synchronized (myENCLock) {
       cache = myExportedNameCache != null ? myExportedNameCache.get() : null;
+      final long modificationStamp = getModificationStamp();
+      if (myExportedNameCache != null && cache != null && modificationStamp != cache.getModificationStamp()) {
+        myExportedNameCache.clear();
+        cache = null;
+      }
       if (cache == null) {
-        cache = new ExportedNameCache();
+        cache = new ExportedNameCache(modificationStamp);
         myExportedNameCache = new SoftReference<ExportedNameCache>(cache);
       }
     }