Expire a mpl2.2-deprecated API (#16184)

Kojoley · web-flow · commit ffa6db072b24 · 2020-01-12T22:33:43.000+03:00
Expire a mpl2.2-deprecated API
diff --git a/doc/api/next_api_changes/behaviour.rst b/doc/api/next_api_changes/behaviour.rst
@@ -62,3 +62,11 @@ property.  This now raises a TypeError.
 `.FileMovieWriter` now defaults to writing temporary frames in a temporary
 directory, which is always cleared at exit.  In order to keep the individual
 frames saved on the filesystem, pass an explicit *frame_prefix*.
+
+`.Axes.plot` no longer accepts *x* and *y* being both 2D and with different numbers of columns
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Previously, calling `.Axes.plot` e.g. with *x* of shape ``(n, 3)`` and *y* of
+shape ``(n, 2)`` would plot the first column of *x* against the first column
+of *y*, the second column of *x* against the second column of *y*, **and** the
+first column of *x* against the third column of *y*.  This now raises an error
+instead.
diff --git a/lib/matplotlib/axes/_base.py b/lib/matplotlib/axes/_base.py
@@ -356,9 +356,7 @@ def _plot_args(self, tup, kwargs):
 
         ncx, ncy = x.shape[1], y.shape[1]
         if ncx > 1 and ncy > 1 and ncx != ncy:
-            cbook.warn_deprecated(
-                "2.2", message="cycling among columns of inputs with "
-                "non-matching shapes is deprecated.")
+            raise ValueError(f"x has {ncx} columns but y has {ncy} columns")
         return [func(x[:, j % ncx], y[:, j % ncy], kw, kwargs)
                 for j in range(max(ncx, ncy))]
 
diff --git a/lib/matplotlib/tests/test_axes.py b/lib/matplotlib/tests/test_axes.py
@@ -5479,12 +5479,13 @@ def test_square_plot():
         ax.get_position(original=False).extents, (0.2125, 0.1, 0.8125, 0.9))
 
 
-def test_no_None():
-    fig, ax = plt.subplots()
+def test_bad_plot_args():
     with pytest.raises(ValueError):
         plt.plot(None)
     with pytest.raises(ValueError):
         plt.plot(None, None)
+    with pytest.raises(ValueError):
+        plt.plot(np.zeros((2, 2)), np.zeros((2, 3)))
 
 
 @pytest.mark.parametrize(
@@ -6227,11 +6228,6 @@ def test_empty_errorbar_legend():
     ax.legend()
 
 
-def test_plot_columns_cycle_deprecation():
-    with pytest.warns(MatplotlibDeprecationWarning):
-        plt.plot(np.zeros((2, 2)), np.zeros((2, 3)))
-
-
 @check_figures_equal(extensions=["png"])
 def test_plot_decimal(fig_test, fig_ref):
     x0 = np.arange(-10, 10, 0.3)
