motief/tests/test_explorer_chart.py

"""Tests for _build_party_axis_figure and load_party_mp_vectors in explorer.py."""

import numpy as np
import plotly.graph_objects as go
import pytest


# ---------------------------------------------------------------------------
# Helpers
# ---------------------------------------------------------------------------


def _make_party_scores(n_parties=3, dim=50):
    """Return a minimal party_scores dict for testing."""
    rng = np.random.default_rng(0)
    names = [f"Party{i}" for i in range(n_parties)]
    return {name: rng.standard_normal(dim).tolist() for name in names}


def _make_theme(flip=False):
    return {
        "label": "Test axis",
        "explanation": "A test axis.",
        "positive_pole": "Left",
        "negative_pole": "Right",
        "flip": flip,
    }


def _make_bootstrap_data(party_scores, dim=50):
    """Build synthetic bootstrap_data matching party_scores keys.

    Party0 gets n_mps=1 (single-MP party → diamond marker).
    Others get n_mps > 1 with a real CI spread.
    """
    rng = np.random.default_rng(1)
    result = {}
    for i, party in enumerate(party_scores):
        centroid = np.array(party_scores[party])
        if i == 0:
            # Single-MP party
            result[party] = {
                "centroid": centroid,
                "ci_lower": centroid.copy(),
                "ci_upper": centroid.copy(),
                "std": np.zeros(dim),
                "n_mps": 1,
            }
        else:
            spread = rng.uniform(0.01, 0.05, size=dim)
            result[party] = {
                "centroid": centroid,
                "ci_lower": centroid - spread,
                "ci_upper": centroid + spread,
                "std": spread / 2,
                "n_mps": 5 + i,
            }
    return result


# ---------------------------------------------------------------------------
# Tests
# ---------------------------------------------------------------------------


class TestBuildPartyAxisFigure:
    """Tests for _build_party_axis_figure (pure Plotly figure construction)."""

    def test_returns_figure_without_bootstrap(self):
        """Basic call without bootstrap → returns go.Figure with 2 traces."""
        from explorer import _build_party_axis_figure

        party_scores = _make_party_scores()
        theme = _make_theme()
        fig = _build_party_axis_figure(party_scores, comp_sel=1, theme=theme)

        assert isinstance(fig, go.Figure)
        assert len(fig.data) == 2  # baseline + markers
        # First trace is the baseline line
        assert fig.data[0].mode == "lines"
        # Second trace is the marker scatter
        assert "markers" in fig.data[1].mode

    def test_returns_none_for_empty_scores(self):
        """Empty party_scores returns None (no figure)."""
        from explorer import _build_party_axis_figure

        fig = _build_party_axis_figure({}, comp_sel=1, theme=_make_theme())
        assert fig is None

    def test_with_bootstrap_has_error_x_and_diamonds(self):
        """Call WITH bootstrap_data → error_x on marker trace, diamond for N=1."""
        from explorer import _build_party_axis_figure

        party_scores = _make_party_scores()
        theme = _make_theme()
        bootstrap_data = _make_bootstrap_data(party_scores)
        fig = _build_party_axis_figure(
            party_scores, comp_sel=1, theme=theme, bootstrap_data=bootstrap_data
        )

        assert isinstance(fig, go.Figure)
        assert len(fig.data) == 2

        marker_trace = fig.data[1]

        # error_x should be present and visible
        assert marker_trace.error_x is not None
        assert marker_trace.error_x.visible is True
        assert marker_trace.error_x.type == "data"
        assert len(marker_trace.error_x.array) == 3  # 3 parties

        # All error bar values should be non-negative
        for err in marker_trace.error_x.array:
            assert err >= 0.0

        # Marker symbols: first party (N=1) → diamond, others → circle
        symbols = list(marker_trace.marker.symbol)
        assert symbols[0] == "diamond"
        assert all(s == "circle" for s in symbols[1:])

    def test_with_bootstrap_hover_includes_n(self):
        """Hover text includes N=<count> for each party."""
        from explorer import _build_party_axis_figure

        party_scores = _make_party_scores()
        theme = _make_theme()
        bootstrap_data = _make_bootstrap_data(party_scores)
        fig = _build_party_axis_figure(
            party_scores, comp_sel=1, theme=theme, bootstrap_data=bootstrap_data
        )

        marker_trace = fig.data[1]
        for ht in marker_trace.hovertext:
            assert "(N=" in ht

    def test_flip_negates_scores_but_error_bars_stay_positive(self):
        """When flip=True, scores are negated but error bar magnitudes stay positive."""
        from explorer import _build_party_axis_figure

        party_scores = _make_party_scores()
        theme_no_flip = _make_theme(flip=False)
        theme_flip = _make_theme(flip=True)
        bootstrap_data = _make_bootstrap_data(party_scores)

        fig_normal = _build_party_axis_figure(
            party_scores, comp_sel=1, theme=theme_no_flip, bootstrap_data=bootstrap_data
        )
        fig_flipped = _build_party_axis_figure(
            party_scores, comp_sel=1, theme=theme_flip, bootstrap_data=bootstrap_data
        )

        normal_scores = list(fig_normal.data[1].x)
        flipped_scores = list(fig_flipped.data[1].x)

        # Scores should be negated
        for ns, fs in zip(normal_scores, flipped_scores):
            assert pytest.approx(ns) == -fs

        # Error bars should be the same (positive) in both cases
        normal_errors = list(fig_normal.data[1].error_x.array)
        flipped_errors = list(fig_flipped.data[1].error_x.array)
        for ne, fe in zip(normal_errors, flipped_errors):
            assert ne >= 0.0
            assert fe >= 0.0
            assert pytest.approx(ne) == fe


class TestLoadPartyMpVectorsImportable:
    """Smoke test: verify load_party_mp_vectors is importable."""

    def test_importable(self):
        from explorer import load_party_mp_vectors

        assert callable(load_party_mp_vectors)