Deprecate is_pyqt5.

anntzer · anntzer · commit 9e5cba566331 · 2020-03-19T18:09:27.000+01:00
The function won't really make sense anymore after the release of
PyQt6.
diff --git a/doc/api/next_api_changes/deprecations.rst b/doc/api/next_api_changes/deprecations.rst
@@ -376,3 +376,8 @@ NavigationToolbar2QT.parent
 This attribute is deprecated.  In order to access the parent window, use
 ``toolbar.canvas.parent()``.  Once the deprecation period is elapsed, it will
 also be accessible as ``toolbar.parent()``.
+
+``qt_compat.is_pyqt5``
+~~~~~~~~~~~~~~~~~~~~~~
+This function is deprecated in prevision of the future release of PyQt6.  The
+Qt version can be checked using ``QtCore.qVersion()``.
diff --git a/examples/user_interfaces/embedding_in_qt_sgskip.py b/examples/user_interfaces/embedding_in_qt_sgskip.py
@@ -14,8 +14,8 @@
 
 import numpy as np
 
-from matplotlib.backends.qt_compat import QtCore, QtWidgets, is_pyqt5
-if is_pyqt5():
+from matplotlib.backends.qt_compat import QtCore, QtWidgets
+if QtCore.qVersion().startswith("5"):
     from matplotlib.backends.backend_qt5agg import (
         FigureCanvas, NavigationToolbar2QT as NavigationToolbar)
 else:
diff --git a/lib/matplotlib/backends/backend_qt5.py b/lib/matplotlib/backends/backend_qt5.py
@@ -106,7 +106,7 @@ def _create_qApp():
         app = QtWidgets.QApplication.instance()
         if app is None:
             # check for DISPLAY env variable on X11 build of Qt
-            if is_pyqt5():
+            if QtCore.qVersion().startswith("5"):
                 try:
                     from PyQt5 import QtX11Extras
                     is_x11_build = True
@@ -129,11 +129,10 @@ def _create_qApp():
         else:
             qApp = app
 
-    if is_pyqt5():
-        try:
-            qApp.setAttribute(QtCore.Qt.AA_UseHighDpiPixmaps)
-        except AttributeError:
-            pass
+    try:
+        qApp.setAttribute(QtCore.Qt.AA_UseHighDpiPixmaps)
+    except AttributeError:
+        pass
 
 
 def _allow_super_init(__init__):
@@ -337,7 +336,7 @@ def mouseReleaseEvent(self, event):
             FigureCanvasBase.button_release_event(self, x, y, button,
                                                   guiEvent=event)
 
-    if is_pyqt5():
+    if QtCore.qVersion().startswith("5"):
         def wheelEvent(self, event):
             x, y = self.mouseEventCoords(event)
             # from QWheelEvent::delta doc
@@ -674,7 +673,7 @@ def parent(self):
         return self._parent
 
     def _icon(self, name, color=None):
-        if is_pyqt5():
+        if QtCore.qVersion().startswith("5"):
             name = name.replace('.png', '_large.png')
         pm = QtGui.QPixmap(os.path.join(self.basedir, name))
         if hasattr(pm, 'setDevicePixelRatio'):
@@ -905,7 +904,7 @@ def __init__(self, toolmanager, parent):
 
     @property
     def _icon_extension(self):
-        if is_pyqt5():
+        if QtCore.qVersion().startswith("5"):
             return '_large.png'
         return '.png'
 
diff --git a/lib/matplotlib/backends/qt_compat.py b/lib/matplotlib/backends/qt_compat.py
@@ -83,6 +83,7 @@ def _isdeleted(obj): return not shiboken2.isValid(obj)
         raise ValueError("Unexpected value for the 'backend.qt5' rcparam")
     _getSaveFileName = QtWidgets.QFileDialog.getSaveFileName
 
+    @mpl.cbook.deprecated("3.3", alternative="QtCore.qVersion()")
     def is_pyqt5():
         return True
 
@@ -138,6 +139,7 @@ def _isdeleted(obj): return not shiboken.isValid(obj)
         raise ValueError("Unexpected value for the 'backend.qt4' rcparam")
     QtWidgets = QtGui
 
+    @mpl.cbook.deprecated("3.3", alternative="QtCore.qVersion()")
     def is_pyqt5():
         return False
 
@@ -174,4 +176,4 @@ def is_pyqt5():
 # These globals are only defined for backcompatibility purposes.
 ETS = dict(pyqt=(QT_API_PYQTv2, 4), pyside=(QT_API_PYSIDE, 4),
            pyqt5=(QT_API_PYQT5, 5), pyside2=(QT_API_PYSIDE2, 5))
-QT_RC_MAJOR_VERSION = 5 if is_pyqt5() else 4
+QT_RC_MAJOR_VERSION = 5 if QtCore.qVersion().startswith("5") else 4
