test(state): add tests for session state management functions

tests/test_state.py

@@ -0,0 +1,121 @@
+"""Tests for session state management functions."""
+
+from unittest.mock import patch
+
+import pandas as pd
+import pytest
+
+from src.config import DIFFICULTY_PRESETS
+
+
+class TestInitSessionState:
+    """Tests for init_session_state."""
+
+    def test_initializes_all_expected_keys(self) -> None:
+        """Verify all default keys are created."""
+        state: dict = {}
+        with patch("src.state.session.st") as mock_st:
+            mock_st.session_state = state
+            from src.state.session import init_session_state
+
+            init_session_state()
+
+        expected_keys = {
+            "home_team",
+            "away_team",
+            "away_team_df",
+            "away_stats",
+            "home_team_df",
+            "radio_index",
+        }
+        assert set(state.keys()) == expected_keys
+
+    def test_does_not_overwrite_existing_values(self) -> None:
+        """Verify calling init twice does not overwrite existing values."""
+        state: dict = {"home_team": ["Player A"]}
+        with patch("src.state.session.st") as mock_st:
+            mock_st.session_state = state
+            from src.state.session import init_session_state
+
+            init_session_state()
+
+        assert state["home_team"] == ["Player A"]
+
+    def test_sets_correct_default_away_stats(self) -> None:
+        """Verify away_stats defaults to Regular difficulty preset."""
+        state: dict = {}
+        with patch("src.state.session.st") as mock_st:
+            mock_st.session_state = state
+            from src.state.session import init_session_state
+
+            init_session_state()
+
+        assert state["away_stats"] == list(DIFFICULTY_PRESETS["Regular"])
+
+    def test_sets_empty_dataframes_by_default(self) -> None:
+        """Verify DataFrames start empty."""
+        state: dict = {}
+        with patch("src.state.session.st") as mock_st:
+            mock_st.session_state = state
+            from src.state.session import init_session_state
+
+            init_session_state()
+
+        assert isinstance(state["away_team_df"], pd.DataFrame)
+        assert state["away_team_df"].empty
+        assert isinstance(state["home_team_df"], pd.DataFrame)
+        assert state["home_team_df"].empty
+
+
+class TestGetAwayStats:
+    """Tests for get_away_stats."""
+
+    def test_returns_stats_from_session(self) -> None:
+        """Verify returns stats when properly set in session."""
+        state: dict = {"away_stats": [100, 200, 300, 400]}
+        with patch("src.state.session.st") as mock_st:
+            mock_st.session_state = state
+            from src.state.session import get_away_stats
+
+            result = get_away_stats()
+
+        assert result == [100, 200, 300, 400]
+
+    def test_returns_defaults_when_invalid(self) -> None:
+        """Verify returns defaults when away_stats is invalid."""
+        state: dict = {"away_stats": "invalid"}
+        with patch("src.state.session.st") as mock_st:
+            mock_st.session_state = state
+            from src.state.session import get_away_stats
+
+            result = get_away_stats()
+
+        assert result == list(DIFFICULTY_PRESETS["Regular"])
+
+
+class TestGetHomeTeamDf:
+    """Tests for get_home_team_df."""
+
+    def test_returns_dataframe_from_session(self) -> None:
+        """Verify returns DataFrame when set in session."""
+        expected_df = pd.DataFrame({"FULL_NAME": ["Player A"]})
+        state: dict = {"home_team_df": expected_df}
+        with patch("src.state.session.st") as mock_st:
+            mock_st.session_state = state
+            from src.state.session import get_home_team_df
+
+            result = get_home_team_df()
+
+        pd.testing.assert_frame_equal(result, expected_df)
+
+    def test_returns_empty_dataframe_when_not_set(self) -> None:
+        """Verify returns empty DataFrame when not set."""
+        state: dict = {}
+        with patch("src.state.session.st") as mock_st:
+            mock_st.session_state = state
+            from src.state.session import get_home_team_df
+
+            result = get_home_team_df()
+
+        assert isinstance(result, pd.DataFrame)
+        assert result.empty