TST: Set check_figures_equal default to PNG only

Author: QuLogic

doc/api/next_api_changes/behavior/29827-ES.rst

@@ -0,0 +1,6 @@
+``matplotlib.testing.check_figures_equal`` defaults to PNG only
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+In most cases, checking that figures are equal with `.check_figures_equal` does not
+depend on the file format. Consequently, the *extensions* parameter now defaults to
+``['png']`` instead of ``['png', 'pdf', 'svg']``, reducing default test requirements.

doc/devel/testing.rst

@@ -191,7 +191,7 @@ vs plotting the circle using the parametric equation of a circle ::
    @check_figures_equal()
    def test_parametric_circle_plot(fig_test, fig_ref):
 
-       xo, yo= (.5, .5)
+       xo = yo = 0.5
        radius = 0.4
 
        ax_test = fig_test.subplots()
@@ -205,7 +205,7 @@ vs plotting the circle using the parametric equation of a circle ::
        ax_ref.add_artist(red_circle_ref)
 
        for ax in [ax_ref, ax_test]:
-           ax.set(xlim=(0,1), ylim=(0,1), aspect='equal')
+           ax.set(xlim=(0, 1), ylim=(0, 1), aspect='equal')
 
 Both comparison decorators have a tolerance argument ``tol`` that is used to specify the
 tolerance for difference in color value between the two images, where 255 is the maximal

lib/matplotlib/testing/decorators.py

@@ -347,7 +347,7 @@ def image_comparison(baseline_images, extensions=None, tol=0,
         savefig_kwargs=savefig_kwarg, style=style)
 
 
-def check_figures_equal(*, extensions=("png", "pdf", "svg"), tol=0):
+def check_figures_equal(*, extensions=("png", ), tol=0):
     """
     Decorator for test cases that generate and compare two figures.
 
@@ -360,7 +360,7 @@ def check_figures_equal(*, extensions=("png", "pdf", "svg"), tol=0):
 
     Parameters
     ----------
-    extensions : list, default: ["png", "pdf", "svg"]
+    extensions : list, default: ["png"]
         The extensions to test.
     tol : float
         The RMS threshold above which the test is considered failed.

lib/matplotlib/tests/test_animation.py

@@ -428,7 +428,7 @@ def update(frame):
         anim._start()
 
 
-@check_figures_equal(extensions=["png"])
+@check_figures_equal()
 def test_animation_frame(tmp_path, fig_test, fig_ref):
     # Test the expected image after iterating through a few frames
     # we save the animation to get the iteration because we are not

lib/matplotlib/tests/test_artist.py

@@ -124,7 +124,7 @@ def test_clipping():
     ax1.set_ylim([-3, 3])
 
 
-@check_figures_equal(extensions=['png'])
+@check_figures_equal()
 def test_clipping_zoom(fig_test, fig_ref):
     # This test places the Axes and sets its limits such that the clip path is
     # outside the figure entirely. This should not break the clip path.