diff --git a/build.gradle.kts b/build.gradle.kts
index 836a946..0a08812 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -4,7 +4,7 @@ plugins {
 }
 
 group = "net.sergeych"
-version = "0.0.6-SNAPSHOT"
+version = "0.0.8-SNAPSHOT"
 
 repositories {
     mavenCentral()
diff --git a/src/commonMain/kotlin/net.sergeych.merge3/merge3.kt b/src/commonMain/kotlin/net.sergeych.merge3/merge3.kt
index a45cfa8..27c85f7 100644
--- a/src/commonMain/kotlin/net.sergeych.merge3/merge3.kt
+++ b/src/commonMain/kotlin/net.sergeych.merge3/merge3.kt
@@ -20,15 +20,22 @@ class MergeResult<T>(
     val changedAreas: List<IntRange>,
     val sourceIndices: MutableList<Int>,
 ) {
+    fun oldIndexOf(i: Int) = sourceIndices.indexOf(i)
+
     val blocks: List<MergedBlock<T>> by lazy {
         if (changedAreas.isEmpty())
-            listOf(MergedBlock.Unchanged(merged, sourceIndices[0]))
+            listOf(MergedBlock.Unchanged(merged, oldIndexOf(0)))
         else {
             val result = mutableListOf<MergedBlock<T>>()
             var start = 0
             for (r in changedAreas) {
                 if (start != r.start) {
-                    result.add(MergedBlock.Unchanged(merged.slice(start until r.start), sourceIndices[start]))
+                    result.add(
+                        MergedBlock.Unchanged(
+                            merged.slice(start until r.start),
+                            oldIndexOf(start)
+                        )
+                    )
                 }
                 if (!r.isEmpty()) {
                     result.add(MergedBlock.Resolved(merged.slice(r)))
diff --git a/src/commonTest/kotlin/testMerge.kt b/src/commonTest/kotlin/testMerge.kt
index 4d95bc0..d0d6957 100644
--- a/src/commonTest/kotlin/testMerge.kt
+++ b/src/commonTest/kotlin/testMerge.kt
@@ -114,8 +114,22 @@ class BasicTest {
         val our = "lssdfasdwerwev".toList()
         val their = "lxcvasdfasdfs".toList()
         val result = merge3(source, their, our)
-        println("got result")
-        val unchanged = result.blocks.filter { it is MergedBlock.Unchanged }
+        println("got result: ${result.toTrace(source)}")
+        println("got result: ${result.blocks}")
+        result.blocks.filter { it is MergedBlock.Unchanged }
+        assertTrue(true)
+    }
+
+    @Test
+    fun testMergeEmpty() {
+        Log.connectConsole()
+        val source = "".toList()
+        val our = "".toList()
+        val their = "".toList()
+        val result = merge3(source, their, our)
+        println("got result: ${result.toTrace(source)}")
+        println("got result: ${result.blocks}")
+        result.blocks.filter { it is MergedBlock.Unchanged }
         assertTrue(true)
     }
 }
\ No newline at end of file