feat: added test to check barplot axes

Author: sharonwoo

pandas/plotting/_matplotlib/core.py

@@ -1805,7 +1805,7 @@ def _kind(self) -> Literal["bar", "barh"]:
     def orientation(self) -> PlottingOrientation:
         return "vertical"
 
-    # GH56611 checks similar to LinePlot's _is_ts_plot and _use_dynamic_x
+    # GH56460 checks similar to LinePlot's _is_ts_plot and _use_dynamic_x
     @final
     def _is_ts_plot(self, data) -> bool:
         return self.use_index and use_dynamic_x(self._get_ax(0), data)

pandas/tests/plotting/test_series.py

@@ -974,6 +974,25 @@ def test_series_none_color(self):
         expected = _unpack_cycler(mpl.pyplot.rcParams)[:1]
         _check_colors(ax.get_lines(), linecolors=expected)
 
+    @pytest.mark.parametrize(
+        "plot_data",
+        [
+            (
+                {
+                    "bars": {-1: 0.5, 0: 1.0, 1: 3.0, 2: 3.5, 3: 1.5},
+                    "pct": {-1: 1.0, 0: 2.0, 1: 3.0, 2: 4.0, 3: 8.0},
+                }
+            )
+        ],
+    )
+    def test_bar_plot_x_axis(self, plot_data):
+        df = DataFrame(plot_data)
+        ax_bar = df["bars"].plot(kind="bar")
+        df["pct"].plot(kind="line")
+        actual_bar_x = [bar.get_x() + bar.get_width() / 2.0 for bar in ax_bar.patches]
+        expected_x = [-1, 0, 1, 2, 3]
+        assert actual_bar_x == expected_x
+
     @pytest.mark.slow
     def test_plot_no_warning(self, ts):
         # GH 55138