Name the collection a chat citation came from

Two collections can hold documents with the same title, and the collapsed
citation carried only that title, so the two read as one source repeated. The
name is appended when the client covers a set, the decision already made for
search results and retrieved images.

haiku_rag_slim/haiku/rag/chat/app.py

@@ -317,7 +317,11 @@ class ChatApp(App):
                         blobs
                     )
 
-        await chat_history.add_citations(citations, picture_bytes=picture_bytes)
+        await chat_history.add_citations(
+            citations,
+            picture_bytes=picture_bytes,
+            include_collection=self.client is not None and self.client.covers_multiple,
+        )
 
         if analysis_data := self._state.get(ANALYSIS_STATE_NAMESPACE):
             analysis_state = AnalysisState.model_validate(analysis_data)

haiku_rag_slim/haiku/rag/chat/widgets/chat_history.py

@@ -118,9 +118,12 @@ class CitationWidget(Collapsible):
         self,
         citation: Citation,
         picture_bytes: list[bytes] | None = None,
+        include_collection: bool = False,
         **kwargs,
     ) -> None:
         title = f"[{citation.index}] {citation.document_title or citation.document_uri}"
+        if include_collection and citation.source:
+            title += f" — {citation.source}"
         if citation.page_numbers:
             pages = ", ".join(map(str, citation.page_numbers[:3]))
             if len(citation.page_numbers) > 3:
@@ -432,14 +435,13 @@ class ChatHistory(VerticalScroll):
         self,
         citations: list[Citation],
         picture_bytes: dict[tuple[str | None, str | None], list[bytes]] | None = None,
+        include_collection: bool = False,
     ) -> None:
         """Add citations inline after a response.
 
         ``picture_bytes`` maps a citation's ``(source, chunk_id)`` → list of raw
-        PNG bytes,
-        one per entry in the citation's ``picture_refs``. Pre-fetched by the
-        caller (typically the chat app's post-response hook) so widget
-        construction stays synchronous.
+        PNG bytes, one per entry in the citation's ``picture_refs``. Pre-fetched
+        by the caller so widget construction stays synchronous.
         """
         if not citations:
             return
@@ -451,6 +453,7 @@ class ChatHistory(VerticalScroll):
                 picture_bytes=picture_bytes.get(
                     qualified_id(citation.source, citation.chunk_id)
                 ),
+                include_collection=include_collection,
             )
             await self.mount(widget)
         self.scroll_end(animate=False)

tests/chat/test_chat_app.py

@@ -806,6 +806,67 @@ class TestRenderingUnattributedPictures:
         ]
 
 
+class TestNamingACitationsCollection:
+    @staticmethod
+    async def _titles(temp_db_path, covering, *sources: str | None) -> list[str]:
+        """The collapsed titles of one citation per source, all named alike."""
+        from haiku.rag.chat.app import RAG_STATE_NAMESPACE
+        from haiku.rag.chat.widgets.chat_history import ChatHistory, CitationWidget
+        from haiku.rag.store.models.citation import Citation
+
+        index = {
+            f"c{position}": Citation(
+                document_id=f"d{position}",
+                chunk_id=f"c{position}",
+                source=source,
+                content="body",
+                document_uri="test://report",
+                document_title="Quarterly report",
+            ).model_dump(mode="json")
+            for position, source in enumerate(sources)
+        }
+
+        app, _ = _make_app(temp_db_path, covering)
+        with (
+            patch("haiku.rag.chat.app.HaikuRAG") as stub,
+            _covering_returns(stub, covering),
+        ):
+            async with app.run_test() as pilot:
+                app._state[RAG_STATE_NAMESPACE] = {
+                    "citations": list(index),
+                    "citation_index": index,
+                }
+                await app._show_citations_and_programs(app.query_one(ChatHistory))
+                await pilot.pause()
+                return [str(w.title) for w in app.query(CitationWidget)]
+
+    @pytest.mark.asyncio
+    async def test_one_title_in_two_collections_reads_as_two_citations(
+        self, temp_db_path: Path
+    ):
+        covering = _make_mock_client()
+        covering.covers_multiple = True
+        covering.source_names = ("alpha", "beta")
+
+        titles = await self._titles(temp_db_path, covering, "alpha", "beta")
+
+        assert len(set(titles)) == 2
+        assert "alpha" in titles[0]
+        assert "beta" in titles[1]
+
+    @pytest.mark.asyncio
+    async def test_one_named_database_is_not_named_on_its_citations(
+        self, temp_db_path: Path
+    ):
+        covering = _make_mock_client()
+        covering.covers_multiple = False
+        covering.source_names = ("alpha",)
+
+        [title] = await self._titles(temp_db_path, covering, "alpha")
+
+        assert "alpha" not in title
+
+
 class TestKeepingSelectionsReachable:
     """A selection applies whether or not the page shows it, and a checkbox is
     the only way to remove one."""