Added missing dependency and improved testing

pyproject.toml

@@ -18,6 +18,8 @@ dependencies = [
     "pypdf>=3.17.0",
     "lxml>=4.9.0",
     "matplotlib>=3.5.0",
+    "citeproc-py>=0.9.0",
+    "citeproc-py-styles>=0.1.5",
 ]
 
 [dependency-groups]

src/lit_agent/identifiers/api.py

@@ -611,17 +611,20 @@ def render_bibliography_to_strings(
         }
 
     try:
-        entries = list(resolution_result.citations.values())
-        style_obj = CitationStylesStyle(style, validate=False, locale=locale)
+        entries = _prepare_citeproc_entries(
+            resolution_result.citations.values(),
+        )
+        style_name = _resolve_csl_style(style)
+        style_obj = CitationStylesStyle(style_name, validate=False, locale=locale)
         source = CiteProcJSON(entries)
         bibliography = CitationStylesBibliography(style_obj, source, formatter.plain)
 
-        for item in source.items:
-            citation = Citation([CitationItem(item.id)])
+        for item_id in source:
+            citation = Citation([CitationItem(item_id)])
             bibliography.register(citation)
 
         rendered = [str(entry) for entry in bibliography.bibliography()]
-        return rendered, {"renderer": "citeproc-py", "style": style, "locale": locale}
+        return rendered, {"renderer": "citeproc", "style": style, "locale": locale}
     except Exception as exc:  # pragma: no cover - defensive
         return _render_compact(resolution_result), {
             "renderer": "fallback",
@@ -678,6 +681,45 @@ def _extract_year(citation: Dict[str, Any]) -> Optional[int]:
     return None
 
 
+def _prepare_citeproc_entries(
+    citations: Iterable[Dict[str, Any]],
+) -> List[Dict[str, Any]]:
+    """Ensure minimal CSL fields are present for citeproc rendering."""
+
+    prepared: List[Dict[str, Any]] = []
+    for index, citation in enumerate(citations, start=1):
+        normalized = dict(citation)
+
+        citation_id = normalized.get("id")
+        normalized["id"] = (
+            str(citation_id) if citation_id not in [None, ""] else str(index)
+        )
+
+        if not normalized.get("type"):
+            normalized["type"] = "article-journal"
+
+        # Remove internal metadata that citeproc does not understand
+        normalized.pop("resolution", None)
+
+        # citeproc expects an iterable for author names
+        if normalized.get("author") is None:
+            normalized["author"] = []
+
+        prepared.append(normalized)
+
+    return prepared
+
+
+def _resolve_csl_style(style: str) -> str:
+    """Map common aliases to valid CSL style identifiers."""
+
+    aliases = {
+        "chicago": "chicago-author-date",
+    }
+    normalized = style.lower()
+    return aliases.get(normalized, normalized)
+
+
 def _import_citeproc():
     """Import citeproc modules, isolated for easier testing."""
 

tests/unit/test_rendering.py

@@ -41,3 +41,189 @@ def raise_import_error():
     assert rendered[0].startswith("[1] Doe Example Paper 2024 10.1234/example")
     assert meta["renderer"] == "fallback"
     assert meta["style"] == "vancouver"
+
+
+@pytest.mark.unit
+def test_render_bibliography_vancouver_style():
+    """Test proper bibliography rendering with vancouver style."""
+    result = CitationResolutionResult(
+        citations={
+            "1": {
+                "id": "1",
+                "title": "Example Paper on Glioblastoma",
+                "author": [{"family": "Doe", "given": "John"}],
+                "issued": {"date-parts": [[2024]]},
+                "container-title": "Nature",
+                "DOI": "10.1234/example",
+                "resolution": {"method": "doi"},
+                "URL": "https://example.com",
+            },
+        },
+        stats={"total": 1, "resolved": 1},
+        failures=[],
+    )
+
+    rendered, meta = render_bibliography_to_strings(result, style="vancouver")
+
+    # Should use citeproc renderer with citeproc-py-styles installed
+    assert meta["renderer"] == "citeproc-py", (
+        "Expected citeproc-py renderer but got fallback. "
+        "Ensure citeproc-py-styles is installed: pip install citeproc-py-styles"
+    )
+    assert meta["style"] == "vancouver"
+    assert meta["locale"] == "en-US"
+
+    # Bibliography should be properly formatted and non-empty
+    assert len(rendered) == 1, "Should have one bibliography entry"
+    assert rendered[0], "Bibliography entry should not be empty"
+    assert "Doe" in rendered[0], "Author name should appear in citation"
+    assert "2024" in rendered[0], "Publication year should appear"
+
+
+@pytest.mark.unit
+def test_render_bibliography_apa_style():
+    """Test bibliography rendering with APA style."""
+    result = CitationResolutionResult(
+        citations={
+            "1": {
+                "id": "1",
+                "title": "Machine Learning in Cancer Research",
+                "author": [
+                    {"family": "Smith", "given": "Jane"},
+                    {"family": "Johnson", "given": "Bob"},
+                ],
+                "issued": {"date-parts": [[2023]]},
+                "container-title": "Cell",
+                "DOI": "10.5678/test",
+                "resolution": {"method": "doi"},
+            },
+        },
+        stats={"total": 1, "resolved": 1},
+        failures=[],
+    )
+
+    rendered, meta = render_bibliography_to_strings(result, style="apa")
+
+    assert meta["renderer"] == "citeproc", (
+        "Expected citeproc renderer. Ensure citeproc-py-styles is installed."
+    )
+    assert meta["style"] == "apa"
+    assert len(rendered) == 1
+    assert "Smith" in rendered[0]
+    assert "2023" in rendered[0]
+
+
+@pytest.mark.unit
+def test_render_bibliography_chicago_style():
+    """Test bibliography rendering with Chicago style."""
+    result = CitationResolutionResult(
+        citations={
+            "1": {
+                "id": "1",
+                "title": "The Role of Inflammation in Disease",
+                "author": [{"family": "Brown", "given": "Alice"}],
+                "issued": {"date-parts": [[2022]]},
+                "container-title": "Science",
+                "DOI": "10.9999/chicago-test",
+                "resolution": {"method": "doi"},
+            },
+        },
+        stats={"total": 1, "resolved": 1},
+        failures=[],
+    )
+
+    rendered, meta = render_bibliography_to_strings(result, style="chicago")
+
+    assert meta["renderer"] == "citeproc-py"
+    assert meta["style"] == "chicago"
+    assert len(rendered) == 1
+    assert rendered[0]  # Non-empty
+
+
+@pytest.mark.unit
+def test_render_bibliography_multiple_citations():
+    """Test rendering multiple citations in correct order."""
+    result = CitationResolutionResult(
+        citations={
+            "1": {
+                "id": "1",
+                "title": "First Paper",
+                "author": [{"family": "Alpha", "given": "A"}],
+                "issued": {"date-parts": [[2021]]},
+                "DOI": "10.1111/first",
+            },
+            "2": {
+                "id": "2",
+                "title": "Second Paper",
+                "author": [{"family": "Beta", "given": "B"}],
+                "issued": {"date-parts": [[2022]]},
+                "DOI": "10.2222/second",
+            },
+            "3": {
+                "id": "3",
+                "title": "Third Paper",
+                "author": [{"family": "Gamma", "given": "C"}],
+                "issued": {"date-parts": [[2023]]},
+                "DOI": "10.3333/third",
+            },
+        },
+        stats={"total": 3, "resolved": 3},
+        failures=[],
+    )
+
+    rendered, meta = render_bibliography_to_strings(result, style="vancouver")
+
+    assert meta["renderer"] == "citeproc"
+    assert len(rendered) == 3, "Should have three bibliography entries"
+
+    # Check all entries are non-empty
+    for entry in rendered:
+        assert entry, "Each bibliography entry should be non-empty"
+
+    # Check authors appear in their respective entries
+    assert "Alpha" in rendered[0]
+    assert "Beta" in rendered[1]
+    assert "Gamma" in rendered[2]
+
+
+@pytest.mark.unit
+def test_render_bibliography_empty_citations():
+    """Test rendering with no citations."""
+    result = CitationResolutionResult(
+        citations={},
+        stats={"total": 0, "resolved": 0},
+        failures=[],
+    )
+
+    rendered, meta = render_bibliography_to_strings(result, style="vancouver")
+
+    # Even with no citations, should use citeproc if available
+    assert meta["renderer"] in ["citeproc-py", "fallback"]
+    assert meta["style"] == "vancouver"
+    assert len(rendered) == 0, "Should have no bibliography entries"
+
+
+@pytest.mark.unit
+def test_render_bibliography_with_locale():
+    """Test bibliography rendering with different locale."""
+    result = CitationResolutionResult(
+        citations={
+            "1": {
+                "id": "1",
+                "title": "Example Paper",
+                "author": [{"family": "Doe", "given": "John"}],
+                "issued": {"date-parts": [[2024]]},
+                "DOI": "10.1234/example",
+            },
+        },
+        stats={"total": 1, "resolved": 1},
+        failures=[],
+    )
+
+    rendered, meta = render_bibliography_to_strings(
+        result, style="vancouver", locale="en-GB"
+    )
+
+    assert meta["renderer"] == "citeproc-py"
+    assert meta["locale"] == "en-GB"
+    assert len(rendered) == 1