Improved tests, fixed docstring

Author: rhshadrach

pandas/plotting/_matplotlib/hist.py

@@ -244,6 +244,7 @@ def _grouped_hist(
     sharey : bool, default False
     rot : int, default 90
     grid : bool, default True
+    legend: : bool, default False
     kwargs : dict, keyword arguments passed to matplotlib.Axes.hist
 
     Returns

pandas/tests/plotting/common.py

@@ -337,15 +337,13 @@ def _check_axes_shape(self, axes, axes_num=None, layout=None, figsize=None):
         visible_axes = self._flatten_visible(axes)
 
         if axes_num is not None:
-            print(len(visible_axes), axes_num)
             assert len(visible_axes) == axes_num
             for ax in visible_axes:
                 # check something drawn on visible axes
                 assert len(ax.get_children()) > 0
 
         if layout is not None:
             result = self._get_axes_layout(_flatten(axes))
-            print(result, layout)
             assert result == layout
 
         tm.assert_numpy_array_equal(

pandas/tests/plotting/test_groupby.py

@@ -6,7 +6,7 @@
 
 import pandas.util._test_decorators as td
 
-from pandas import DataFrame, Series
+from pandas import DataFrame, Index, Series
 import pandas._testing as tm
 from pandas.tests.plotting.common import TestPlotBase
 
@@ -69,14 +69,15 @@ def test_plot_kwargs(self):
 
 
 @td.skip_if_no_mpl
-@pytest.mark.parametrize("column", [None, "B"])
-@pytest.mark.parametrize("label", [None, "D"])
+@pytest.mark.parametrize("column", [None, "b"])
+@pytest.mark.parametrize("label", [None, "d"])
 def test_hist_with_legend(column, label):
-    df = DataFrame(np.random.randn(30, 2), columns=["A", "B"])
-    df["C"] = 15 * ["a"] + 15 * ["b"]
-    g = df.groupby("C")
+    index = Index(15 * [1] + 15 * [2], name="c")
+    df = DataFrame(np.random.randn(30, 2), index=index, columns=["a", "b"])
+    g = df.groupby("c")
+
     g.hist(column=column, label=label, legend=True)
     tm.close()
-    if column != "B":
-        g["A"].hist(label=label, legend=True)
+    if column != "b":
+        g["a"].hist(label=label, legend=True)
         tm.close()

pandas/tests/plotting/test_hist_method.py

@@ -6,7 +6,7 @@
 
 import pandas.util._test_decorators as td
 
-from pandas import DataFrame, Series
+from pandas import DataFrame, Index, Series
 import pandas._testing as tm
 from pandas.tests.plotting.common import TestPlotBase, _check_plot_works
 
@@ -294,32 +294,26 @@ def test_hist_column_order_unchanged(self, column, expected):
         assert result == expected
 
     @pytest.mark.slow
-    @pytest.mark.parametrize("column", [None, "B"])
-    @pytest.mark.parametrize("label", [None, "D"])
-    def test_hist_with_legend(self, column, label):
-        kwargs = {'legend': True}
+    @pytest.mark.parametrize("by", [None, "b"])
+    @pytest.mark.parametrize("label", [None, "c"])
+    def test_hist_with_legend(self, by, label):
+        expected_labels = label or "a"
+        expected_axes_num = 1 if by is None else 2
+        expected_layout = (1, 1) if by is None else (1, 2)
+
+        index = 15 * [1] + 15 * [2]
+        s = Series(np.random.randn(30), index=index, name="a")
+        s.index.name = "b"
+
+        kwargs = {"legend": True, "by": by}
         if label is not None:
-            kwargs['label'] = label
-        if column is not None:
-            kwargs['column'] = column
-
-        columns = ["A", "B"]
-        df = DataFrame(np.random.randn(30, 2), columns=columns)
-        df["C"] = 15 * ["a"] + 15 * ["b"]
-        df = df.set_index("C")
-        _check_plot_works(df.hist, **kwargs)
-        axes = df.hist(**kwargs)
-
-        axes_num = 2 if column is None else 1
-        layout = (1, 2) if column is None else (1, 1)
-        self._check_axes_shape(axes, axes_num=axes_num, layout=layout)
+            # Behavior differs if kwargs contains "label": None
+            kwargs["label"] = label
 
-        for labels, axis in zip(columns, axes[0]):
-            if column is not None:
-                labels = ["B"]
-            if label is not None:
-                labels = ["D"]
-            self._check_legend_labels([axis], labels)
+        _check_plot_works(s.hist, **kwargs)
+        axes = s.hist(**kwargs)
+        self._check_axes_shape(axes, axes_num=expected_axes_num, layout=expected_layout)
+        self._check_legend_labels(axes, expected_labels)
 
 
 @td.skip_if_no_mpl
@@ -514,26 +508,28 @@ def test_axis_share_xy(self):
         assert ax2._shared_y_axes.joined(ax1, ax2)
 
     @pytest.mark.slow
-    @pytest.mark.parametrize("column", [None, "B"])
-    @pytest.mark.parametrize("label", [None, "D"])
-    def test_hist_with_legend(self, column, label):
-        kwargs = {'legend': True, "by": "C"}
+    @pytest.mark.parametrize("by", [None, "c"])
+    @pytest.mark.parametrize("column", [None, "b"])
+    @pytest.mark.parametrize("label", [None, "d"])
+    def test_hist_with_legend(self, by, column, label):
+        expected_axes_num = 1 if by is None and column is not None else 2
+        expected_layout = (1, expected_axes_num)
+        expected_labels = label or column or ["a", "b"]
+        if by is not None:
+            expected_labels = [expected_labels] * 2
+
+        index = Index(15 * [1] + 15 * [2], name="c")
+        df = DataFrame(np.random.randn(30, 2), index=index, columns=["a", "b"])
+
+        kwargs = {"legend": True, "by": by, "column": column}
         if label is not None:
-            kwargs['label'] = label
-        if column is not None:
-            kwargs['column'] = column
-
-        columns = ["A", "B"]
-        df = DataFrame(np.random.randn(30, 2), columns=columns)
-        df["C"] = 15 * ["a"] + 15 * ["b"]
-        df = df.set_index("C")
+            # Behavior differs if kwargs contains "label": None
+            kwargs["label"] = label
+
         _check_plot_works(df.hist, **kwargs)
         axes = df.hist(**kwargs)
-
-        self._check_axes_shape(axes, axes_num=2, layout=(1, 2))
-        labels = columns
-        if column is not None:
-            labels = ["B"]
-        if label is not None:
-            labels = ["D"]
-        self._check_legend_labels(axes, labels)
+        self._check_axes_shape(axes, axes_num=expected_axes_num, layout=expected_layout)
+        if by is None:
+            axes = axes[0]
+        for expected_label, ax in zip(expected_labels, axes):
+            self._check_legend_labels(ax, expected_label)