diff --git a/platform/diff-api/src/com/intellij/ide/diff/DiffElement.java b/platform/diff-api/src/com/intellij/ide/diff/DiffElement.java
index 1a1b7720444d..bcc01178ab9e 100644
--- a/platform/diff-api/src/com/intellij/ide/diff/DiffElement.java
+++ b/platform/diff-api/src/com/intellij/ide/diff/DiffElement.java
@@ -115,7 +115,7 @@ public abstract class DiffElement<T> {
   }
 
   @Nullable
-  public Callable<DiffElement<T>> getElementChooser(Project project) {
+  public Callable<DiffElement<T>> getElementChooser(@Nullable Project project) {
     return null;
   }
 
diff --git a/platform/diff-impl/src/com/intellij/diff/tools/dir/DirDiffViewer.java b/platform/diff-impl/src/com/intellij/diff/tools/dir/DirDiffViewer.java
index 2622b5571555..89e3fde820f5 100644
--- a/platform/diff-impl/src/com/intellij/diff/tools/dir/DirDiffViewer.java
+++ b/platform/diff-impl/src/com/intellij/diff/tools/dir/DirDiffViewer.java
@@ -35,8 +35,6 @@ import com.intellij.openapi.actionSystem.PlatformDataKeys;
 import com.intellij.openapi.diff.impl.dir.DirDiffPanel;
 import com.intellij.openapi.diff.impl.dir.DirDiffTableModel;
 import com.intellij.openapi.diff.impl.dir.DirDiffWindow;
-import com.intellij.openapi.project.DefaultProjectFactory;
-import com.intellij.openapi.project.Project;
 import com.intellij.openapi.util.Disposer;
 import com.intellij.util.ObjectUtils;
 import org.jetbrains.annotations.NotNull;
@@ -44,7 +42,6 @@ import org.jetbrains.annotations.Nullable;
 
 import javax.swing.*;
 import java.awt.*;
-import java.io.IOException;
 import java.util.Arrays;
 import java.util.List;
 
@@ -69,9 +66,7 @@ class DirDiffViewer implements FrameDiffTool.DiffViewer {
                 @Nullable String helpID) {
     myHelpID = helpID;
 
-    Project project = context.getProject();
-    if (project == null) project = DefaultProjectFactory.getInstance().getDefaultProject();
-    DirDiffTableModel model = new DirDiffTableModel(project, element1, element2, settings);
+    DirDiffTableModel model = new DirDiffTableModel(context.getProject(), element1, element2, settings);
 
     myDirDiffPanel = new DirDiffPanel(model, new DirDiffWindow() {
       @NotNull
diff --git a/platform/diff-impl/src/com/intellij/openapi/diff/impl/dir/DirDiffTableModel.java b/platform/diff-impl/src/com/intellij/openapi/diff/impl/dir/DirDiffTableModel.java
index b5d072709729..130ca9c1393b 100644
--- a/platform/diff-impl/src/com/intellij/openapi/diff/impl/dir/DirDiffTableModel.java
+++ b/platform/diff-impl/src/com/intellij/openapi/diff/impl/dir/DirDiffTableModel.java
@@ -74,7 +74,7 @@ public class DirDiffTableModel extends AbstractTableModel implements DirDiffMode
   public static final String COLUMN_DATE = "Date";
   public static final String EMPTY_STRING = StringUtil.repeatSymbol(' ', 50);
 
-  private final Project myProject;
+  @Nullable private final Project myProject;
   private final DirDiffSettings mySettings;
 
   private DiffElement mySource;
@@ -91,7 +91,7 @@ public class DirDiffTableModel extends AbstractTableModel implements DirDiffMode
   private DirDiffPanel myPanel;
   private volatile boolean myDisposed;
 
-  public DirDiffTableModel(@NotNull Project project, DiffElement source, DiffElement target, DirDiffSettings settings) {
+  public DirDiffTableModel(@Nullable Project project, DiffElement source, DiffElement target, DirDiffSettings settings) {
     UsageTrigger.trigger("diff.DirDiffTableModel");
     myProject = project;
     mySettings = settings;
@@ -528,6 +528,7 @@ public class DirDiffTableModel extends AbstractTableModel implements DirDiffMode
     return "";
   }
 
+  @Nullable
   public Project getProject() {
     return myProject;
   }