diff --git a/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/lambda/newLambda/IDEA126809.java b/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/lambda/newLambda/IDEA126809.java
new file mode 100644
index 000000000000..df910d96e710
--- /dev/null
+++ b/java/java-tests/testData/codeInsight/daemonCodeAnalyzer/lambda/newLambda/IDEA126809.java
@@ -0,0 +1,27 @@
+import java.util.Optional;
+import java.util.Set;
+import java.util.stream.Stream;
+
+import static java.util.stream.Collectors.toSet;
+
+class App {
+
+  {
+    final User user = new User("test", Stream.of("TEST").collect(toSet()));
+    Optional.of(user).map(u -> new User(u.getName(),
+                                        u.getAttributes().stream().filter(a -> !a.equals("TEST")).collect(toSet())));
+  }
+
+  private static final class User {
+    User(final String name, final Set<String> attributes) {
+    }
+
+    public String getName() {
+      return null;
+    }
+
+    public Set<String> getAttributes() {
+      return null;
+    }
+  }
+}
diff --git a/java/java-tests/testSrc/com/intellij/codeInsight/daemon/lambda/NewLambdaHighlightingTest.java b/java/java-tests/testSrc/com/intellij/codeInsight/daemon/lambda/NewLambdaHighlightingTest.java
index df8c50339f35..6bd7654b72af 100644
--- a/java/java-tests/testSrc/com/intellij/codeInsight/daemon/lambda/NewLambdaHighlightingTest.java
+++ b/java/java-tests/testSrc/com/intellij/codeInsight/daemon/lambda/NewLambdaHighlightingTest.java
@@ -238,6 +238,10 @@ public class NewLambdaHighlightingTest extends LightDaemonAnalyzerTestCase {
     doTest();
   }
 
+  public void testIDEA126809() throws Exception {
+    doTest();
+  }
+
   private void doTest() {
     doTest(false);
   }