IDEA-133960 Fix IndexTest#_test language level change

java/java-tests/testSrc/com/intellij/index/IndexTest.groovy

@@ -33,6 +33,7 @@ import com.intellij.psi.*
 import com.intellij.psi.codeStyle.CodeStyleManager
 import com.intellij.psi.impl.PsiManagerEx
 import com.intellij.psi.impl.file.impl.FileManagerImpl
+import com.intellij.psi.impl.source.PostprocessReformattingAspect
 import com.intellij.psi.impl.source.PsiFileWithStubSupport
 import com.intellij.psi.search.GlobalSearchScope
 import com.intellij.psi.search.PsiSearchHelper
@@ -338,6 +339,25 @@ public class IndexTest extends JavaCodeInsightFixtureTestCase {
     assert ((PsiJavaFile)psiFile).importList.node
   }
 
+  public void "test language level change2"() {
+    def psiFile = myFixture.addFileToProject("Foo.java", "class Foo {}")
+    def vFile = psiFile.virtualFile
+    def scope = GlobalSearchScope.allScope(project)
+
+    psiFile.add(elementFactory.createEnum("SomeEnum"))
+
+    CodeStyleManager.getInstance(getProject()).reformat(psiFile)
+    PostprocessReformattingAspect.getInstance(getProject()).doPostponedFormatting()
+
+    assert JavaPsiFacade.getInstance(project).findClass("Foo", scope)
+
+    IdeaTestUtil.setModuleLanguageLevel(myFixture.module, LanguageLevel.JDK_1_3)
+    assert ((PsiJavaFile)getPsiManager().findFile(vFile)).importList.node
+
+    PlatformTestUtil.tryGcSoftlyReachableObjects()
+    assert ((PsiJavaFile)getPsiManager().findFile(vFile)).importList.node
+  }
+
   public void "test changing a file without psi makes the document committed and updates index"() {
     def psiFile = myFixture.addFileToProject("Foo.java", "class Foo {}")
     def vFile = psiFile.virtualFile

platform/lang-impl/src/com/intellij/util/indexing/FileBasedIndexImpl.java

@@ -1982,7 +1982,7 @@ public class FileBasedIndexImpl extends FileBasedIndex {
                 }
 
                 if (!myUpToDateIndicesForUnsavedOrTransactedDocuments.isEmpty()) {
-                  clearPsiIndicesForUnsavedDocuments(file);
+                  clearUpToDateStateForPsiIndicesOfUnsavedDocuments(file);
                 }
               }
               finally {
@@ -2068,6 +2068,8 @@ public class FileBasedIndexImpl extends FileBasedIndex {
             }
           }
 
+          clearUpToDateStateForPsiIndicesOfUnsavedDocuments(file);
+
           // the file is for sure not a dir and it was previously indexed by at least one index AND it belongs to some update set
           if (!isTooLarge(file) && getIndexableSetForFile(file) != null) scheduleForUpdate(file);
         }
@@ -2320,12 +2322,19 @@ public class FileBasedIndexImpl extends FileBasedIndex {
     }
   }
 
-  private boolean clearPsiIndicesForUnsavedDocuments(@NotNull VirtualFile file) {
-    Document document = myFileDocumentManager.getDocument(file);
+  private boolean clearUpToDateStateForPsiIndicesOfUnsavedDocuments(@NotNull VirtualFile file) {
+    Document document = myFileDocumentManager.getCachedDocument(file);
+
     if (document != null && myFileDocumentManager.isDocumentUnsaved(document)) {
-      for (ID<?, ?> psiBackedIndex : myPsiDependentIndices) {
-        myUpToDateIndicesForUnsavedOrTransactedDocuments.remove(psiBackedIndex);
+      if (!myUpToDateIndicesForUnsavedOrTransactedDocuments.isEmpty()) {
+        for (ID<?, ?> psiBackedIndex : myPsiDependentIndices) {
+          myUpToDateIndicesForUnsavedOrTransactedDocuments.remove(psiBackedIndex);
+        }
       }
+
+      myLastIndexedDocStamps.clearForDocument(document); // Q: non psi indices
+      document.putUserData(ourFileContentKey, null);
+
       return true;
     }
     return false;
@@ -2472,7 +2481,7 @@ public class FileBasedIndexImpl extends FileBasedIndex {
             PsiFile file = event.getFile();
             if (file != null) {
               VirtualFile virtualFile = file.getVirtualFile();
-              if (!clearPsiIndicesForUnsavedDocuments(virtualFile)) {
+              if (!clearUpToDateStateForPsiIndicesOfUnsavedDocuments(virtualFile)) {
                 // change in persistent file
                 if (virtualFile instanceof VirtualFileWithId) {
                   int fileId = ((VirtualFileWithId)virtualFile).getId();

platform/lang-impl/src/com/intellij/util/indexing/PerIndexDocumentVersionMap.java

@@ -67,6 +67,9 @@ public class PerIndexDocumentVersionMap {
     }
   }
 
+  public void clearForDocument(@NotNull Document document) {
+    document.putUserData(KEY, new ArrayList<IdVersionInfo>());
+  }
   public void clear() {
     mapVersion++;
   }