From 4040ee86a9c3a921567ad4faf7b6ab8e4dcfb4d3 Mon Sep 17 00:00:00 2001
From: Wojtek <wskozlowski@dbzero.io>
Date: Mon, 1 Jun 2026 17:12:52 +0200
Subject: [PATCH] crash fix ?

---
 .../collections/b_index/bindex_iterator.hpp   |  3 +++
 tests/unit_tests/MorphingBIndexTest.cpp       | 19 +++++++++++++++++++
 2 files changed, 22 insertions(+)

diff --git a/src/dbzero/core/collections/b_index/bindex_iterator.hpp b/src/dbzero/core/collections/b_index/bindex_iterator.hpp
index a268ca16..98838d07 100644
--- a/src/dbzero/core/collections/b_index/bindex_iterator.hpp
+++ b/src/dbzero/core/collections/b_index/bindex_iterator.hpp
@@ -665,6 +665,9 @@ namespace db0::bindex::iterator
         }
 
         bool is_end() const {
+            if (!m_ptr) {
+                return true;
+            }
             return m_functions.m_is_end_ptr(m_ptr);
         }
 
diff --git a/tests/unit_tests/MorphingBIndexTest.cpp b/tests/unit_tests/MorphingBIndexTest.cpp
index 2fe1e177..38f4d7b0 100644
--- a/tests/unit_tests/MorphingBIndexTest.cpp
+++ b/tests/unit_tests/MorphingBIndexTest.cpp
@@ -205,6 +205,25 @@ namespace tests
 		ASSERT_NO_THROW( db0::MorphingBIndex<uint64_t>::joinable_const_iterator() );
 	}
 
+	TEST_F( MorphingBIndexTest , testDefaultIteratorIsEnd )
+	{
+        db0::MorphingBIndex<std::uint64_t>::joinable_const_iterator cut;
+
+        ASSERT_TRUE(cut.is_end());
+	}
+
+	TEST_F( MorphingBIndexTest , testResetIteratorIsEnd )
+	{
+        auto memspace = getMemspace();
+        db0::MorphingBIndex<std::uint64_t> index(memspace, 123u);
+        auto cut = index.beginJoin(1);
+
+        ASSERT_FALSE(cut.is_end());
+        cut.reset();
+
+        ASSERT_TRUE(cut.is_end());
+	}
+
 	TEST_F( MorphingBIndexTest , testAssignmentOperatorIsAllowed )
 	{
         auto memspace = getMemspace();