Add test for citations.py (#117)

* used AI to generate several tests to hit 100% statement coverage in citations.py

* fix formatting

Author: yangm2

backend/tests/test_citations.py

@@ -0,0 +1,43 @@
+import pytest
+from flask import Flask
+from tenantfirstaid.citations import get_citation, SECTIONS
+
+
+@pytest.fixture
+def app():
+    app = Flask(__name__)
+    app.add_url_rule("/api/citation", view_func=get_citation, methods=["GET"])
+    return app
+
+
+@pytest.fixture
+def client(app):
+    return app.test_client()
+
+
+def test_get_citation_success(client):
+    # Use a valid section from SECTIONS
+    section = next(iter(SECTIONS))
+    response = client.get(f"/api/citation?section={section}")
+    assert response.status_code == 200
+    data = response.get_json()
+    assert data["section"] == section
+    assert data["text"] == SECTIONS[section]
+
+
+def test_get_citation_missing_param(client):
+    response = client.get("/api/citation")
+    assert response.status_code == 400
+    assert b"missing query param" in response.data
+
+
+def test_get_citation_unknown_section(client):
+    response = client.get("/api/citation?section=notarealsection")
+    assert response.status_code == 404
+    assert b"not found" in response.data
+
+
+def test_get_citation_empty_section_param(client):
+    response = client.get("/api/citation?section=")
+    assert response.status_code == 400
+    assert b"missing query param" in response.data