May 27, 2025 · May 25, 2025
diff --git a/lib/matplotlib/_constrained_layout.py b/lib/matplotlib/_constrained_layout.py
    See test_constrained_layout::test_constrained_layout12 for an example.
    """

    axsdone = []
    for sfig in fig.subfigs:
        match_submerged_margins(layoutgrids, sfig)
 axsdone +=match_submerged_margins(layoutgrids, sfig)

    axs = [a for a in fig.get_axes()
           if a.get_subplotspec() is not None and a.get_in_layout()]
           if (a.get_subplotspec() is not None and a.get_in_layout() and
               a not in axsdone)]

    for ax1 in axs:
        ss1 = ax1.get_subplotspec()
            for i in ss1.rowspan[:-1]:
                lg1.edit_margin_min('bottom', maxsubb, cell=i)

    return axs


 def get_cb_parent_spans(cbax):
    """
diff --git a/lib/matplotlib/tests/test_constrainedlayout.py b/lib/matplotlib/tests/test_constrainedlayout.py
    gc.collect()
    assert not any(isinstance(obj, mpl._layoutgrid.LayoutGrid)
                   for obj in gc.get_objects())


 def test_submerged_subfig():
    """
    Test that the submerged margin logic does not get called multiple times
    on same axes if it is already in a subfigure
    """
    fig = plt.figure(figsize=(4, 5), layout='constrained')
    figures = fig.subfigures(3, 1)
    axs = []
    for f in figures.flatten():
        gs = f.add_gridspec(2, 2)
        for i in range(2):
            axs += [f.add_subplot(gs[i, 0])]
            axs[-1].plot()
        f.add_subplot(gs[:, 1]).plot()
    fig.draw_without_rendering()
    for ax in axs[1:]:
        assert np.allclose(ax.get_position().bounds[-1],
                           axs[0].get_position().bounds[-1], atol=1e-6)
Original file line number	Diff line number	Diff line change
Expand Up		@@ -521,11 +521,13 @@ def match_submerged_margins(layoutgrids, fig):
		See test_constrained_layout::test_constrained_layout12 for an example.
		"""

		axsdone = []
		for sfig in fig.subfigs:
		match_submerged_margins(layoutgrids, sfig)
		axsdone +=match_submerged_margins(layoutgrids, sfig)

		axs = [a for a in fig.get_axes()
		if a.get_subplotspec() is not None and a.get_in_layout()]
		if (a.get_subplotspec() is not None and a.get_in_layout() and
		a not in axsdone)]

		for ax1 in axs:
		ss1 = ax1.get_subplotspec()
Expand DownExpand Up		@@ -592,6 +594,8 @@ def match_submerged_margins(layoutgrids, fig):
		for i in ss1.rowspan[:-1]:
		lg1.edit_margin_min('bottom', maxsubb, cell=i)

		return axs


		def get_cb_parent_spans(cbax):
		"""
Expand Down
Original file line number	Diff line number	Diff line change
Expand Up		@@ -721,3 +721,23 @@ def test_layout_leak():
		gc.collect()
		assert not any(isinstance(obj, mpl._layoutgrid.LayoutGrid)
		for obj in gc.get_objects())


		def test_submerged_subfig():
		"""
		Test that the submerged margin logic does not get called multiple times
		on same axes if it is already in a subfigure
		"""
		fig = plt.figure(figsize=(4, 5), layout='constrained')
		figures = fig.subfigures(3, 1)
		axs = []
		for f in figures.flatten():
		gs = f.add_gridspec(2, 2)
		for i in range(2):
		axs += [f.add_subplot(gs[i, 0])]
		axs[-1].plot()
		f.add_subplot(gs[:, 1]).plot()
		fig.draw_without_rendering()
		for ax in axs[1:]:
		assert np.allclose(ax.get_position().bounds[-1],
		axs[0].get_position().bounds[-1], atol=1e-6)