Add testing for grid.major/minor.* in rcParams

konmenel · konmenel · commit 456034cd0496 · 2025-01-29T17:25:49.000Z
diff --git a/lib/matplotlib/tests/test_axis.py b/lib/matplotlib/tests/test_axis.py
@@ -67,3 +67,31 @@ def test_get_tick_position_tick_params():
                    right=True, labelright=True, left=False, labelleft=False)
     assert ax.xaxis.get_ticks_position() == "top"
     assert ax.yaxis.get_ticks_position() == "right"
+
+
+def test_grid_rcparams():
+    """Tests that `grid.major/minor.*` overwrites `grid.*` in rcParams."""
+    plt.rcParams.update({
+        "axes.grid": True, "axes.grid.which": "both",
+        "ytick.minor.visible": True, "xtick.minor.visible": True,
+    })
+    def_linewidth = plt.rcParams["grid.linewidth"]
+    def_linestyle = plt.rcParams["grid.linestyle"]
+    def_alpha = plt.rcParams["grid.alpha"]
+
+    plt.rcParams.update({
+        "grid.color": "gray","grid.minor.color": "red",
+        "grid.major.linestyle": ":", "grid.major.linewidth": 2,
+        "grid.minor.alpha": 0.6,
+    })
+    _, ax = plt.subplots()
+    ax.plot([0, 1])
+
+    assert ax.xaxis.get_major_ticks()[0].gridline.get_color() == "gray"
+    assert ax.xaxis.get_minor_ticks()[0].gridline.get_color() == "red"
+    assert ax.xaxis.get_major_ticks()[0].gridline.get_linewidth() == 2
+    assert ax.xaxis.get_minor_ticks()[0].gridline.get_linewidth() == def_linewidth
+    assert ax.xaxis.get_major_ticks()[0].gridline.get_linestyle() == ":"
+    assert ax.xaxis.get_minor_ticks()[0].gridline.get_linestyle() == def_linestyle
+    assert ax.xaxis.get_major_ticks()[0].gridline.get_alpha() == def_alpha
+    assert ax.xaxis.get_minor_ticks()[0].gridline.get_alpha() == 0.6
