tickminorvisible-fix (matplotlib#12938)

Author: ImportanceOfBeingErnest

lib/matplotlib/scale.py

@@ -69,7 +69,8 @@ def set_default_locators_and_formatters(self, axis):
         axis.set_major_formatter(ScalarFormatter())
         axis.set_minor_formatter(NullFormatter())
         # update the minor locator for x and y axis based on rcParams
-        if rcParams['xtick.minor.visible']:
+        if (axis.axis_name == 'x' and rcParams['xtick.minor.visible']
+            or axis.axis_name == 'y' and rcParams['ytick.minor.visible']):
             axis.set_minor_locator(AutoMinorLocator())
         else:
             axis.set_minor_locator(NullLocator())

lib/matplotlib/tests/test_ticker.py

@@ -851,3 +851,21 @@ def test_minlocator_type():
     fig, ax = plt.subplots()
     with pytest.raises(TypeError):
         ax.xaxis.set_minor_locator(matplotlib.ticker.LogFormatter())
+
+
+def test_minorticks_rc():
+    fig = plt.figure()
+
+    def minorticksubplot(xminor, yminor, i):
+        rc = {'xtick.minor.visible': xminor,
+              'ytick.minor.visible': yminor}
+        with plt.rc_context(rc=rc):
+            ax = fig.add_subplot(2, 2, i)
+
+        assert (len(ax.xaxis.get_minor_ticks()) > 0) == xminor
+        assert (len(ax.yaxis.get_minor_ticks()) > 0) == yminor
+
+    minorticksubplot(False, False, 1)
+    minorticksubplot(True, False, 2)
+    minorticksubplot(False, True, 3)
+    minorticksubplot(True, True, 4)