Support ax.grid(visible=<bool>).

anntzer · anntzer · commit 06d1f560bfc1 · 2020-10-18T21:08:20.000+02:00
Remove the separate _gridOnMajor/_gridOnMinor attributes and store
visibility together with all other grid attributes in the
_major_tick_kw/_minor_tick_kw dicts under the "gridOn" key.  This makes
it possible to update just that entry in `Axis.grid`.

Also, don't normalize `b` to True `if len(kwargs)` in `Axes.grid`:
we need to keep it as `None`, normalizing it only to True/False in
`Axis.grid` (which handles that just fine), so that `Axis.grid` can
handle the consistency checks between `b` and `visible`.
diff --git a/lib/matplotlib/axes/_base.py b/lib/matplotlib/axes/_base.py
@@ -2976,8 +2976,6 @@ def grid(self, b=None, which='major', axis='both', **kwargs):
         use `.set_axisbelow` or, for more control, call the
         `~.Artist.set_zorder` method of each axis.
         """
-        if len(kwargs):
-            b = True
         _api.check_in_list(['x', 'y', 'both'], axis=axis)
         if axis in ['x', 'both']:
             self.xaxis.grid(b, which=which, **kwargs)
diff --git a/lib/matplotlib/axis.py b/lib/matplotlib/axis.py
@@ -790,10 +790,10 @@ def clear(self):
         self.callbacks = cbook.CallbackRegistry()
 
         # whether the grids are on
-        self._gridOnMajor = (
+        self._major_tick_kw['gridOn'] = (
                 mpl.rcParams['axes.grid'] and
                 mpl.rcParams['axes.grid.which'] in ('both', 'major'))
-        self._gridOnMinor = (
+        self._minor_tick_kw['gridOn'] = (
                 mpl.rcParams['axes.grid'] and
                 mpl.rcParams['axes.grid.which'] in ('both', 'minor'))
 
@@ -1398,7 +1398,6 @@ def get_major_ticks(self, numticks=None):
             # Update the new tick label properties from the old.
             tick = self._get_tick(major=True)
             self.majorTicks.append(tick)
-            tick.gridline.set_visible(self._gridOnMajor)
             self._copy_tick_props(self.majorTicks[0], tick)
 
         return self.majorTicks[:numticks]
@@ -1412,7 +1411,6 @@ def get_minor_ticks(self, numticks=None):
             # Update the new tick label properties from the old.
             tick = self._get_tick(major=False)
             self.minorTicks.append(tick)
-            tick.gridline.set_visible(self._gridOnMinor)
             self._copy_tick_props(self.minorTicks[0], tick)
 
         return self.minorTicks[:numticks]
@@ -1437,32 +1435,37 @@ def grid(self, b=None, which='major', **kwargs):
             Define the line properties of the grid, e.g.::
 
                 grid(color='r', linestyle='-', linewidth=2)
-
         """
-        if len(kwargs):
-            if not b and b is not None:  # something false-like but not None
+        if b is not None:
+            if 'visible' in kwargs and bool(b) != bool(kwargs['visible']):
+                raise ValueError(
+                    "'b' and 'visible' specify inconsistent grid visibilities")
+            if kwargs and not b:  # something false-like but not None
                 cbook._warn_external('First parameter to grid() is false, '
                                      'but line properties are supplied. The '
                                      'grid will be enabled.')
-            b = True
+                b = True
         which = which.lower()
         _api.check_in_list(['major', 'minor', 'both'], which=which)
         gridkw = {'grid_' + item[0]: item[1] for item in kwargs.items()}
+        if 'grid_visible' in gridkw:
+            forced_visibility = True
+            gridkw['gridOn'] = gridkw.pop('grid_visible')
+        else:
+            forced_visibility = False
 
         if which in ['minor', 'both']:
-            if b is None:
-                self._gridOnMinor = not self._gridOnMinor
-            else:
-                self._gridOnMinor = b
-            self.set_tick_params(which='minor', gridOn=self._gridOnMinor,
-                                 **gridkw)
+            if b is None and not forced_visibility:
+                gridkw['gridOn'] = not self._minor_tick_kw['gridOn']
+            elif b is not None:
+                gridkw['gridOn'] = b
+            self.set_tick_params(which='minor', **gridkw)
         if which in ['major', 'both']:
-            if b is None:
-                self._gridOnMajor = not self._gridOnMajor
-            else:
-                self._gridOnMajor = b
-            self.set_tick_params(which='major', gridOn=self._gridOnMajor,
-                                 **gridkw)
+            if b is None and not forced_visibility:
+                gridkw['gridOn'] = not self._major_tick_kw['gridOn']
+            elif b is not None:
+                gridkw['gridOn'] = b
+            self.set_tick_params(which='major', **gridkw)
         self.stale = True
 
     def update_units(self, data):
diff --git a/lib/matplotlib/tests/test_axes.py b/lib/matplotlib/tests/test_axes.py
@@ -4577,25 +4577,35 @@ def test_twin_spines_on_top():
     ax2.fill_between("i", "j", color='#7FC97F', alpha=.5, data=data)
 
 
-def test_rcparam_grid_minor():
-    orig_grid = matplotlib.rcParams['axes.grid']
-    orig_locator = matplotlib.rcParams['axes.grid.which']
-
-    matplotlib.rcParams['axes.grid'] = True
-
-    values = (
-        ('both', (True, True)),
-        ('major', (True, False)),
-        ('minor', (False, True))
-        )
+@pytest.mark.parametrize("grid_which, major_visible, minor_visible", [
+    ("both", True, True),
+    ("major", True, False),
+    ("minor", False, True),
+])
+def test_rcparam_grid_minor(grid_which, major_visible, minor_visible):
+    mpl.rcParams.update({"axes.grid": True, "axes.grid.which": grid_which})
+    fig, ax = plt.subplots()
+    fig.canvas.draw()
+    assert all(tick.gridline.get_visible() == major_visible
+               for tick in ax.xaxis.majorTicks)
+    assert all(tick.gridline.get_visible() == minor_visible
+               for tick in ax.xaxis.minorTicks)
 
-    for locator, result in values:
-        matplotlib.rcParams['axes.grid.which'] = locator
-        fig, ax = plt.subplots()
-        assert (ax.xaxis._gridOnMajor, ax.xaxis._gridOnMinor) == result
 
-    matplotlib.rcParams['axes.grid'] = orig_grid
-    matplotlib.rcParams['axes.grid.which'] = orig_locator
+def test_grid():
+    fig, ax = plt.subplots()
+    ax.grid()
+    fig.canvas.draw()
+    assert ax.xaxis.majorTicks[0].gridline.get_visible()
+    ax.grid(visible=False)
+    fig.canvas.draw()
+    assert not ax.xaxis.majorTicks[0].gridline.get_visible()
+    ax.grid(visible=True)
+    fig.canvas.draw()
+    assert ax.xaxis.majorTicks[0].gridline.get_visible()
+    ax.grid()
+    fig.canvas.draw()
+    assert not ax.xaxis.majorTicks[0].gridline.get_visible()
 
 
 def test_vline_limit():
