From 9e94a4253d191abcbdcc23d3b33a6bc2a55e1dae Mon Sep 17 00:00:00 2001
From: Alexey Kudravtsev <cdr@intellij.com>
Date: Wed, 7 Sep 2016 14:10:16 +0300
Subject: [PATCH] make VirtualFilePointerManager more responsive to VFS changes
 to update virtual file pointers sooner to fix EA-87976 - assert:
 RootIndex.ensureValid

---
 .../impl/VirtualFilePointerManagerImpl.java   |  8 ++++
 .../vfs/impl/VirtualFilePointerTest.java      | 45 +++++++++++++++++++
 2 files changed, 53 insertions(+)

diff --git a/platform/platform-impl/src/com/intellij/openapi/vfs/impl/VirtualFilePointerManagerImpl.java b/platform/platform-impl/src/com/intellij/openapi/vfs/impl/VirtualFilePointerManagerImpl.java
index f3c9556bc864..ab9982938fa0 100644
--- a/platform/platform-impl/src/com/intellij/openapi/vfs/impl/VirtualFilePointerManagerImpl.java
+++ b/platform/platform-impl/src/com/intellij/openapi/vfs/impl/VirtualFilePointerManagerImpl.java
@@ -26,6 +26,7 @@ import com.intellij.openapi.vfs.*;
 import com.intellij.openapi.vfs.ex.temp.TempFileSystem;
 import com.intellij.openapi.vfs.newvfs.BulkFileListener;
 import com.intellij.openapi.vfs.newvfs.events.*;
+import com.intellij.openapi.vfs.newvfs.persistent.PersistentFS;
 import com.intellij.openapi.vfs.pointers.VirtualFilePointer;
 import com.intellij.openapi.vfs.pointers.VirtualFilePointerContainer;
 import com.intellij.openapi.vfs.pointers.VirtualFilePointerListener;
@@ -529,6 +530,13 @@ public class VirtualFilePointerManagerImpl extends VirtualFilePointerManager imp
     }
   }
 
+  @Override
+  public long getModificationCount() {
+    // depend on PersistentFS.getInstance().getStructureModificationCount() because com.intellij.openapi.vfs.impl.FilePointerPartNode.update is
+    // depend on its own modcount because we need to change both before and after VFS changes
+    return super.getModificationCount() + PersistentFS.getInstance().getStructureModificationCount();
+  }
+
   private static class DelegatingDisposable implements Disposable {
     private static final ConcurrentMap<Disposable, DelegatingDisposable> ourInstances =
       ContainerUtil.newConcurrentMap(ContainerUtil.<Disposable>identityStrategy());
diff --git a/platform/platform-tests/testSrc/com/intellij/openapi/vfs/impl/VirtualFilePointerTest.java b/platform/platform-tests/testSrc/com/intellij/openapi/vfs/impl/VirtualFilePointerTest.java
index bd95921a2892..d8b7072ecf93 100644
--- a/platform/platform-tests/testSrc/com/intellij/openapi/vfs/impl/VirtualFilePointerTest.java
+++ b/platform/platform-tests/testSrc/com/intellij/openapi/vfs/impl/VirtualFilePointerTest.java
@@ -23,7 +23,11 @@ import com.intellij.openapi.application.ex.PathManagerEx;
 import com.intellij.openapi.command.WriteCommandAction;
 import com.intellij.openapi.roots.ModuleRootManager;
 import com.intellij.openapi.roots.OrderRootType;
+import com.intellij.openapi.roots.ProjectRootManager;
 import com.intellij.openapi.roots.impl.OrderEntryUtil;
+import com.intellij.openapi.roots.libraries.Library;
+import com.intellij.openapi.roots.libraries.LibraryTable;
+import com.intellij.openapi.roots.libraries.LibraryUtil;
 import com.intellij.openapi.util.Computable;
 import com.intellij.openapi.util.Disposer;
 import com.intellij.openapi.util.io.FileUtil;
@@ -792,4 +796,45 @@ public class VirtualFilePointerTest extends PlatformTestCase {
     assertEquals(dir2, p1.getFile());
     assertEquals(dir2, p2.getFile());
   }
+
+  public void testVirtualPointersMustBeAlreadyUpToDateInVFSChangeListeners() throws IOException {
+    File tempDirectory = createTempDirectory();
+    final VirtualFile root = LocalFileSystem.getInstance().refreshAndFindFileByIoFile(tempDirectory);
+
+    VirtualFile dir1 = createChildDirectory(root, "dir1");
+    VirtualFile file = createChildData(dir1, "x.txt");
+    setFileText(file, "xxxxxx");
+
+    PsiTestUtil.addLibrary(getModule(), dir1.getPath());
+
+    VirtualFileAdapter listener = new VirtualFileAdapter() {
+      @Override
+      public void fileDeleted(@NotNull VirtualFileEvent event) {
+        ProjectRootManager.getInstance(getProject()).getFileIndex().getModuleForFile(dir1);
+      }
+    };
+    LocalFileSystem.getInstance().addVirtualFileListener(listener);
+    Disposer.register(disposable, () -> LocalFileSystem.getInstance().removeVirtualFileListener(listener));
+
+    assertTrue(FileUtil.delete(new File(dir1.getPath())));
+    System.out.println("deleted "+dir1);
+
+    try {
+      while (root.findChild("dir1") != null) {
+        UIUtil.dispatchAllInvocationEvents();
+        LocalFileSystem.getInstance().refresh(false);
+      }
+    }
+    finally {
+      ApplicationManager.getApplication().runWriteAction(() -> {
+        Library library = LibraryUtil.findLibrary(getModule(), "dir1");
+        LibraryTable.ModifiableModel model = library.getTable().getModifiableModel();
+        model.removeLibrary(library);
+        model.commit();
+      });
+
+
+      PsiTestUtil.removeAllRoots(getModule(), null);
+    }
+  }
 }