backend/src/test/java/org/raddatz/familienarchiv/service/TranscriptionServiceTest.java

@@ -241,6 +241,35 @@ class TranscriptionServiceTest {
                 .containsExactly(mention);
     }
 
+    @Test
+    void updateBlock_clearsPriorMentions_beforeApplyingDto() {
+        UUID docId = UUID.randomUUID();
+        UUID blockId = UUID.randomUUID();
+
+        PersonMention prior = new PersonMention(UUID.randomUUID(), "Heinrich");
+        PersonMention incoming = new PersonMention(UUID.randomUUID(), "Auguste");
+
+        TranscriptionBlock block = TranscriptionBlock.builder()
+                .id(blockId).documentId(docId).text("old").build();
+        block.getMentionedPersons().add(prior);
+
+        when(blockRepository.findByIdAndDocumentId(blockId, docId)).thenReturn(Optional.of(block));
+        when(blockRepository.save(any())).thenAnswer(inv -> inv.getArgument(0));
+        when(documentService.getDocumentById(any())).thenReturn(
+                Document.builder().scriptType(ScriptType.TYPEWRITER).build());
+
+        UpdateTranscriptionBlockDTO dto = UpdateTranscriptionBlockDTO.builder()
+                .text("@Auguste text")
+                .mentionedPersons(List.of(incoming))
+                .build();
+
+        TranscriptionBlock result = transcriptionService.updateBlock(docId, blockId, dto, UUID.randomUUID());
+
+        assertThat(result.getMentionedPersons())
+                .containsExactly(incoming)
+                .doesNotContain(prior);
+    }
+
     @Test
     void updateBlock_triggersTraining_whenKurrentSenderPresent() {
         UUID docId = UUID.randomUUID();