Initial commit

venv/lib/python3.10/site-packages/matplotlib/backends/qt_compat.py

@@ -0,0 +1,159 @@
+"""
+Qt binding and backend selector.
+
+The selection logic is as follows:
+- if any of PyQt6, PySide6, PyQt5, or PySide2 have already been
+  imported (checked in that order), use it;
+- otherwise, if the QT_API environment variable (used by Enthought) is set, use
+  it to determine which binding to use;
+- otherwise, use whatever the rcParams indicate.
+"""
+
+import operator
+import os
+import platform
+import sys
+
+from packaging.version import parse as parse_version
+
+import matplotlib as mpl
+
+from . import _QT_FORCE_QT5_BINDING
+
+QT_API_PYQT6 = "PyQt6"
+QT_API_PYSIDE6 = "PySide6"
+QT_API_PYQT5 = "PyQt5"
+QT_API_PYSIDE2 = "PySide2"
+QT_API_ENV = os.environ.get("QT_API")
+if QT_API_ENV is not None:
+    QT_API_ENV = QT_API_ENV.lower()
+_ETS = {  # Mapping of QT_API_ENV to requested binding.
+    "pyqt6": QT_API_PYQT6, "pyside6": QT_API_PYSIDE6,
+    "pyqt5": QT_API_PYQT5, "pyside2": QT_API_PYSIDE2,
+}
+# First, check if anything is already imported.
+if sys.modules.get("PyQt6.QtCore"):
+    QT_API = QT_API_PYQT6
+elif sys.modules.get("PySide6.QtCore"):
+    QT_API = QT_API_PYSIDE6
+elif sys.modules.get("PyQt5.QtCore"):
+    QT_API = QT_API_PYQT5
+elif sys.modules.get("PySide2.QtCore"):
+    QT_API = QT_API_PYSIDE2
+# Otherwise, check the QT_API environment variable (from Enthought).  This can
+# only override the binding, not the backend (in other words, we check that the
+# requested backend actually matches).  Use _get_backend_or_none to avoid
+# triggering backend resolution (which can result in a partially but
+# incompletely imported backend_qt5).
+elif (mpl.rcParams._get_backend_or_none() or "").lower().startswith("qt5"):
+    if QT_API_ENV in ["pyqt5", "pyside2"]:
+        QT_API = _ETS[QT_API_ENV]
+    else:
+        _QT_FORCE_QT5_BINDING = True  # noqa: F811
+        QT_API = None
+# A non-Qt backend was selected but we still got there (possible, e.g., when
+# fully manually embedding Matplotlib in a Qt app without using pyplot).
+elif QT_API_ENV is None:
+    QT_API = None
+elif QT_API_ENV in _ETS:
+    QT_API = _ETS[QT_API_ENV]
+else:
+    raise RuntimeError(
+        "The environment variable QT_API has the unrecognized value {!r}; "
+        "valid values are {}".format(QT_API_ENV, ", ".join(_ETS)))
+
+
+def _setup_pyqt5plus():
+    global QtCore, QtGui, QtWidgets, __version__
+    global _isdeleted, _to_int
+
+    if QT_API == QT_API_PYQT6:
+        from PyQt6 import QtCore, QtGui, QtWidgets, sip
+        __version__ = QtCore.PYQT_VERSION_STR
+        QtCore.Signal = QtCore.pyqtSignal
+        QtCore.Slot = QtCore.pyqtSlot
+        QtCore.Property = QtCore.pyqtProperty
+        _isdeleted = sip.isdeleted
+        _to_int = operator.attrgetter('value')
+    elif QT_API == QT_API_PYSIDE6:
+        from PySide6 import QtCore, QtGui, QtWidgets, __version__
+        import shiboken6
+        def _isdeleted(obj): return not shiboken6.isValid(obj)
+        if parse_version(__version__) >= parse_version('6.4'):
+            _to_int = operator.attrgetter('value')
+        else:
+            _to_int = int
+    elif QT_API == QT_API_PYQT5:
+        from PyQt5 import QtCore, QtGui, QtWidgets
+        import sip
+        __version__ = QtCore.PYQT_VERSION_STR
+        QtCore.Signal = QtCore.pyqtSignal
+        QtCore.Slot = QtCore.pyqtSlot
+        QtCore.Property = QtCore.pyqtProperty
+        _isdeleted = sip.isdeleted
+        _to_int = int
+    elif QT_API == QT_API_PYSIDE2:
+        from PySide2 import QtCore, QtGui, QtWidgets, __version__
+        try:
+            from PySide2 import shiboken2
+        except ImportError:
+            import shiboken2
+        def _isdeleted(obj):
+            return not shiboken2.isValid(obj)
+        _to_int = int
+    else:
+        raise AssertionError(f"Unexpected QT_API: {QT_API}")
+
+
+if QT_API in [QT_API_PYQT6, QT_API_PYQT5, QT_API_PYSIDE6, QT_API_PYSIDE2]:
+    _setup_pyqt5plus()
+elif QT_API is None:  # See above re: dict.__getitem__.
+    if _QT_FORCE_QT5_BINDING:
+        _candidates = [
+            (_setup_pyqt5plus, QT_API_PYQT5),
+            (_setup_pyqt5plus, QT_API_PYSIDE2),
+        ]
+    else:
+        _candidates = [
+            (_setup_pyqt5plus, QT_API_PYQT6),
+            (_setup_pyqt5plus, QT_API_PYSIDE6),
+            (_setup_pyqt5plus, QT_API_PYQT5),
+            (_setup_pyqt5plus, QT_API_PYSIDE2),
+        ]
+    for _setup, QT_API in _candidates:
+        try:
+            _setup()
+        except ImportError:
+            continue
+        break
+    else:
+        raise ImportError(
+            "Failed to import any of the following Qt binding modules: {}"
+            .format(", ".join([QT_API for _, QT_API in _candidates]))
+        )
+else:  # We should not get there.
+    raise AssertionError(f"Unexpected QT_API: {QT_API}")
+_version_info = tuple(QtCore.QLibraryInfo.version().segments())
+
+
+if _version_info < (5, 12):
+    raise ImportError(
+        f"The Qt version imported is "
+        f"{QtCore.QLibraryInfo.version().toString()} but Matplotlib requires "
+        f"Qt>=5.12")
+
+
+# Fixes issues with Big Sur
+# https://bugreports.qt.io/browse/QTBUG-87014, fixed in qt 5.15.2
+if (sys.platform == 'darwin' and
+        parse_version(platform.mac_ver()[0]) >= parse_version("10.16") and
+        _version_info < (5, 15, 2)):
+    os.environ.setdefault("QT_MAC_WANTS_LAYER", "1")
+
+
+# Backports.
+
+
+def _exec(obj):
+    # exec on PyQt6, exec_ elsewhere.
+    obj.exec() if hasattr(obj, "exec") else obj.exec_()