Merge pull request matplotlib#20170 from anntzer/spv

SubplotParams.validate-associated fixes.

Author: timhoffm

doc/api/next_api_changes/deprecations/20170-AL.rst

@@ -0,0 +1,4 @@
+``SubplotParams.validate``
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+... is deprecated.  Use `.SubplotParams.update` to change `.SubplotParams`
+while always keeping it in a valid state.

lib/matplotlib/_api/deprecation.py

@@ -282,18 +282,20 @@ class Foo:
             attr = _deprecate_privatize_attribute(*args, **kwargs)
 
     where *all* parameters are forwarded to `deprecated`.  This form makes
-    ``attr`` a property which forwards access to ``self._attr`` (same name but
-    with a leading underscore), with a deprecation warning.  Note that the
-    attribute name is derived from *the name this helper is assigned to*.  This
-    helper also works for deprecating methods.
+    ``attr`` a property which forwards read and write access to ``self._attr``
+    (same name but with a leading underscore), with a deprecation warning.
+    Note that the attribute name is derived from *the name this helper is
+    assigned to*.  This helper also works for deprecating methods.
     """
 
     def __init__(self, *args, **kwargs):
         self.deprecator = deprecated(*args, **kwargs)
 
     def __set_name__(self, owner, name):
         setattr(owner, name, self.deprecator(
-            property(lambda self: getattr(self, f"_{name}")), name=name))
+            property(lambda self: getattr(self, f"_{name}"),
+                     lambda self, value: setattr(self, f"_{name}", value)),
+            name=name))
 
 
 def rename_parameter(since, old, new, func=None):

lib/matplotlib/backends/backend_qt5.py

@@ -777,12 +777,6 @@ def __init__(self, targetfig, parent):
 
         self._figure = targetfig
 
-        for lower, higher in [("bottom", "top"), ("left", "right")]:
-            self._widgets[lower].valueChanged.connect(
-                lambda val: self._widgets[higher].setMinimum(val + .001))
-            self._widgets[higher].valueChanged.connect(
-                lambda val: self._widgets[lower].setMaximum(val - .001))
-
         self._attrs = ["top", "bottom", "left", "right", "hspace", "wspace"]
         self._defaults = {attr: vars(self._figure.subplotpars)[attr]
                           for attr in self._attrs}
@@ -821,7 +815,12 @@ def _export_values(self):
         dialog.exec_()
 
     def _on_value_changed(self):
-        self._figure.subplots_adjust(**{attr: self._widgets[attr].value()
+        widgets = self._widgets
+        # Set all mins and maxes, so that this can also be used in _reset().
+        for lower, higher in [("bottom", "top"), ("left", "right")]:
+            widgets[higher].setMinimum(widgets[lower].value() + .001)
+            widgets[lower].setMaximum(widgets[higher].value() - .001)
+        self._figure.subplots_adjust(**{attr: widgets[attr].value()
                                         for attr in self._attrs})
         self._figure.canvas.draw_idle()
 
@@ -836,7 +835,12 @@ def _tight_layout(self):
 
     def _reset(self):
         for attr, value in self._defaults.items():
-            self._widgets[attr].setValue(value)
+            widget = self._widgets[attr]
+            widget.setRange(0, 1)
+            widget.blockSignals(True)
+            widget.setValue(value)
+            widget.blockSignals(False)
+        self._on_value_changed()
 
 
 class ToolbarQt(ToolContainerBase, QtWidgets.QToolBar):

lib/matplotlib/figure.py

@@ -120,6 +120,7 @@ class SubplotParams:
     """
     A class to hold the parameters for a subplot.
     """
+
     def __init__(self, left=None, bottom=None, right=None, top=None,
                  wspace=None, hspace=None):
         """
@@ -146,17 +147,20 @@ def __init__(self, left=None, bottom=None, right=None, top=None,
             The height of the padding between subplots,
             as a fraction of the average Axes height.
         """
-        self.validate = True
+        self._validate = True
         for key in ["left", "bottom", "right", "top", "wspace", "hspace"]:
             setattr(self, key, mpl.rcParams[f"figure.subplot.{key}"])
         self.update(left, bottom, right, top, wspace, hspace)
 
+    # Also remove _validate after deprecation elapses.
+    validate = _api.deprecate_privatize_attribute("3.5")
+
     def update(self, left=None, bottom=None, right=None, top=None,
                wspace=None, hspace=None):
         """
         Update the dimensions of the passed parameters. *None* means unchanged.
         """
-        if self.validate:
+        if self._validate:
             if ((left if left is not None else self.left)
                     >= (right if right is not None else self.right)):
                 raise ValueError('left cannot be >= right')

lib/matplotlib/tests/test_api.py

@@ -37,14 +37,19 @@ def f(cls):
 def test_deprecate_privatize_attribute():
     class C:
         def __init__(self): self._attr = 1
-        def _meth(self, arg): pass
+        def _meth(self, arg): return arg
         attr = _api.deprecate_privatize_attribute("0.0")
         meth = _api.deprecate_privatize_attribute("0.0")
 
+    c = C()
     with pytest.warns(_api.MatplotlibDeprecationWarning):
-        C().attr
+        assert c.attr == 1
     with pytest.warns(_api.MatplotlibDeprecationWarning):
-        C().meth(42)
+        c.attr = 2
+    with pytest.warns(_api.MatplotlibDeprecationWarning):
+        assert c.attr == 2
+    with pytest.warns(_api.MatplotlibDeprecationWarning):
+        assert c.meth(42) == 42
 
 
 def test_delete_parameter():

lib/matplotlib/widgets.py

@@ -1402,11 +1402,7 @@ def __init__(self, targetfig, toolfig):
 
         bax = toolfig.add_axes([0.8, 0.05, 0.15, 0.075])
         self.buttonreset = Button(bax, 'Reset')
-
-        # During reset there can be a temporary invalid state depending on the
-        # order of the reset so we turn off validation for the resetting
-        with cbook._setattr_cm(toolfig.subplotpars, validate=False):
-            self.buttonreset.on_clicked(self._on_reset)
+        self.buttonreset.on_clicked(self._on_reset)
 
     def _on_slider_changed(self, _):
         self.targetfig.subplots_adjust(
@@ -1417,17 +1413,19 @@ def _on_slider_changed(self, _):
 
     def _on_reset(self, event):
         with ExitStack() as stack:
-            # Temporarily disable drawing on self and self's sliders.
+            # Temporarily disable drawing on self and self's sliders, and
+            # disconnect slider events (as the subplotparams can be temporarily
+            # invalid, depending on the order in which they are restored).
             stack.enter_context(cbook._setattr_cm(self, drawon=False))
             for slider in self._sliders:
-                stack.enter_context(cbook._setattr_cm(slider, drawon=False))
+                stack.enter_context(
+                    cbook._setattr_cm(slider, drawon=False, eventson=False))
             # Reset the slider to the initial position.
             for slider in self._sliders:
                 slider.reset()
-        # Draw the canvas.
         if self.drawon:
-            event.canvas.draw()
-            self.targetfig.canvas.draw()
+            event.canvas.draw()  # Redraw the subplottool canvas.
+        self._on_slider_changed(None)  # Apply changes to the target window.
 
     axleft = _api.deprecated("3.3")(
         property(lambda self: self.sliderleft.ax))