[pyqgis] add QgsSettings.enumValue and flagValue to the bindings (#7024)

* [pyqgis] add QgsSettings.enumValue and flagValue to the bindings

these are done in pure Python since no implementation is possible in SIP

there is a dirty hack for flags since QgsMapLayerProxyModel.Filters.__qualname__
returns 'Filters' and not 'QgsMapLayerProxyModel.Filters'

* fix typo

python/core/__init__.py

@@ -35,6 +35,7 @@
 from .additions.qgsfeature import mapping_feature
 from .additions.qgsfunction import register_function, qgsfunction
 from .additions.qgsgeometry import _geometryNonZero, mapping_geometry
+from .additions.qgssettings import _qgssettings_enum_value, _qgssettings_flag_value
 from .additions.qgstaskwrapper import QgsTaskWrapper
 from .additions.readwritecontextentercategory import ReadWriteContextEnterCategory
 
@@ -48,27 +49,36 @@
 QgsProcessingOutputLayerDefinition.__repr__ = processing_output_layer_repr
 QgsProject.blockDirtying = ProjectDirtyBlocker
 QgsReadWriteContext.enterCategory = ReadWriteContextEnterCategory
+QgsSettings.enumValue = _qgssettings_enum_value
+QgsSettings.flagValue = _qgssettings_flag_value
 QgsTask.fromFunction = fromFunction
 
 # -----------------
 # DO NOT EDIT BELOW
 # These are automatically added by calling sipify.pl script
-QgsTolerance.UnitType.baseClass = QgsTolerance
+
 QgsAuthManager.MessageLevel.baseClass = QgsAuthManager
 QgsDataItem.Type.baseClass = QgsDataItem
 QgsDataItem.State.baseClass = QgsDataItem
 QgsLayerItem.LayerType.baseClass = QgsLayerItem
 QgsDataProvider.DataCapability.baseClass = QgsDataProvider
 QgsDataSourceUri.SslMode.baseClass = QgsDataSourceUri
+QgsFieldProxyModel.Filters.baseClass = QgsFieldProxyModel
+Filters = QgsFieldProxyModel  # dirty hack since SIP seems to introduce the flags in module
+QgsMapLayerProxyModel.Filters.baseClass = QgsMapLayerProxyModel
+Filters = QgsMapLayerProxyModel  # dirty hack since SIP seems to introduce the flags in module
 QgsNetworkContentFetcherRegistry.FetchingMode.baseClass = QgsNetworkContentFetcherRegistry
 QgsSnappingConfig.SnappingMode.baseClass = QgsSnappingConfig
 QgsSnappingConfig.SnappingType.baseClass = QgsSnappingConfig
+QgsTolerance.UnitType.baseClass = QgsTolerance
 QgsUnitTypes.DistanceUnit.baseClass = QgsUnitTypes
 QgsUnitTypes.AreaUnit.baseClass = QgsUnitTypes
 QgsUnitTypes.AngleUnit.baseClass = QgsUnitTypes
 QgsUnitTypes.RenderUnit.baseClass = QgsUnitTypes
 QgsUnitTypes.LayoutUnit.baseClass = QgsUnitTypes
 QgsVectorSimplifyMethod.SimplifyHint.baseClass = QgsVectorSimplifyMethod
+QgsVectorSimplifyMethod.SimplifyHints.baseClass = QgsVectorSimplifyMethod
+SimplifyHints = QgsVectorSimplifyMethod  # dirty hack since SIP seems to introduce the flags in module
 QgsVectorSimplifyMethod.SimplifyAlgorithm.baseClass = QgsVectorSimplifyMethod
 QgsRasterProjector.Precision.baseClass = QgsRasterProjector
 QgsAbstractGeometry.SegmentationToleranceType.baseClass = QgsAbstractGeometry

python/core/additions/metaenum.py

@@ -18,11 +18,27 @@
 """
 
 
-def metaEnumFromValue(enumValue, raiseException=True, baseClass=None):
-    return metaEnumFromType(enumValue.__class__, raiseException, baseClass)
+def metaEnumFromValue(enumValue, baseClass=None, raiseException=True):
+    """
+    Returns the QMetaEnum for an enum value.
+    The enum must have declared using the Q_ENUM macro
+    :param enumValue: the enum value
+    :param baseClass: the enum base class. If not given, it will try to get it by using `enumValue.__class__.baseClass`
+    :param raiseException: if False, no exception will be raised and None will be return in case of failure
+    :return: the QMetaEnum if it succeeds, None otherwise
+    """
+    return metaEnumFromType(enumValue.__class__, baseClass, raiseException)
 
 
-def metaEnumFromType(enumClass, raiseException=True, baseClass=None):
+def metaEnumFromType(enumClass, baseClass=None, raiseException=True):
+    """
+    Returns the QMetaEnum for an enum type.
+    The enum must have declared using the Q_ENUM macro
+    :param enumClass: the enum class
+    :param baseClass: the enum base class. If not given, it will try to get it by using `enumValue.__class__.baseClass`
+    :param raiseException: if False, no exception will be raised and None will be return in case of failure
+    :return: the QMetaEnum if it succeeds, None otherwise
+    """
     if enumClass == int:
         if raiseException:
             raise TypeError("enumClass is an int, while it should be an enum")
@@ -32,7 +48,7 @@ def metaEnumFromType(enumClass, raiseException=True, baseClass=None):
     if baseClass is None:
         try:
             baseClass = enumClass.baseClass
-            return metaEnumFromType(enumClass, raiseException, baseClass)
+            return metaEnumFromType(enumClass, baseClass, raiseException)
         except AttributeError:
             if raiseException:
                 raise ValueError("Enum type does not implement baseClass method. Provide the base class as argument.")

python/core/additions/qgssettings.py

@@ -0,0 +1,101 @@
+# -*- coding: utf-8 -*-
+
+"""
+***************************************************************************
+    qgssettings.py
+    ---------------------
+    Date                 : May 2018
+    Copyright            : (C) 2018 by Denis Rouzaud
+    Email                : denis@opengis.ch
+***************************************************************************
+*                                                                         *
+*   This program is free software; you can redistribute it and/or modify  *
+*   it under the terms of the GNU General Public License as published by  *
+*   the Free Software Foundation; either version 2 of the License, or     *
+*   (at your option) any later version.                                   *
+*                                                                         *
+***************************************************************************
+"""
+
+from .metaenum import metaEnumFromValue
+import qgis
+
+
+def _qgssettings_enum_value(self, key, enumDefaultValue, section=None):
+    """
+    Return the setting value for a setting based on an enum.
+    This forces the output to be a valid and existing entry of the enum.
+    Hence if the setting value is incorrect, the given default value is returned.
+    This tries first with setting as a string (as the enum) and then as an integer value.
+
+    :param self: the QgsSettings object
+    :param key: the setting key
+    :param enumDefaultValue: the default value as an enum value
+    :param section: optional section
+    :return: the setting value
+
+     .. note::  The enum needs to be declared with Q_ENUM.
+
+    """
+    if section is None:
+        section = self.NoSection
+
+    meta_enum = metaEnumFromValue(enumDefaultValue)
+    if meta_enum is None or not meta_enum.isValid():
+        # this should not happen
+        raise ValueError("could not get the meta enum for given enum default value (type: {})".format(type(enumDefaultValue)))
+
+    str_val = self.value(key, meta_enum.valueToKey(enumDefaultValue))
+    # need a new meta enum as QgsSettings.value is making a copy and leads to seg fault (proaby a PyQt issue)
+    meta_enum_2 = metaEnumFromValue(enumDefaultValue)
+    (enu_val, ok) = meta_enum_2.keyToValue(str_val)
+
+    if not ok:
+        enu_val = enumDefaultValue
+
+    return enu_val
+
+
+def _qgssettings_flag_value(self, key, flagDefaultValue, section=None):
+    """
+    Return the setting value for a setting based on a flag.
+    This forces the output to be a valid and existing entry of the enum.
+    Hence if the setting value is incorrect, the given default value is returned.
+    This tries first with setting as a string (as the enum) and then as an integer value.
+
+    :param self: the QgsSettings object
+    :param key: the setting key
+    :param flagDefaultValue: the default value as a flag value
+    :param section: optional section
+    :return: the setting value
+
+     .. note::  The flag needs to be declared with Q_FLAG (not Q_FLAGS).
+
+    """
+    if section is None:
+        section = self.NoSection
+
+    # There is an issue in SIP, flags.__class__ does not return the proper class
+    # (e.g. Filters instead of QgsMapLayerProxyModel.Filters)
+    # dirty hack to get the parent class
+    __import__(flagDefaultValue.__module__)
+    baseClass = None
+    exec("baseClass={module}.{flag_class}".format(module=flagDefaultValue.__module__.replace('_', ''),
+                                                  flag_class=flagDefaultValue.__class__.__name__))
+
+    meta_enum = metaEnumFromValue(flagDefaultValue, baseClass)
+    if meta_enum is None or not meta_enum.isValid():
+        # this should not happen
+        raise ValueError("could not get the meta enum for given enum default value (type: {})".format(type(flagDefaultValue)))
+
+    str_val = self.value(key, meta_enum.valueToKey(flagDefaultValue))
+    # need a new meta enum as QgsSettings.value is making a copy and leads to seg fault (proaby a PyQt issue)
+    meta_enum_2 = metaEnumFromValue(flagDefaultValue)
+    (flag_val, ok) = meta_enum_2.keysToValue(str_val)
+
+    if not ok:
+        flag_val = flagDefaultValue
+    else:
+        flag_val = flagDefaultValue.__class__(flag_val)
+
+    return flag_val

python/gui/__init__.py

@@ -30,12 +30,20 @@
 # DO NOT EDIT BELOW
 # These are automatically added by calling sipify.pl script
 QgsAuthSettingsWidget.WarningType.baseClass = QgsAuthSettingsWidget
+QgsAdvancedDigitizingDockWidget.CadCapacities.baseClass = QgsAdvancedDigitizingDockWidget
+CadCapacities = QgsAdvancedDigitizingDockWidget  # dirty hack since SIP seems to introduce the flags in module
 QgsColorButton.Behavior.baseClass = QgsColorButton
 QgsColorTextWidget.ColorTextFormat.baseClass = QgsColorTextWidget
 QgsFilterLineEdit.ClearMode.baseClass = QgsFilterLineEdit
 QgsFloatingWidget.AnchorPoint.baseClass = QgsFloatingWidget
 QgsFontButton.Mode.baseClass = QgsFontButton
+QgsMapLayerAction.Targets.baseClass = QgsMapLayerAction
+Targets = QgsMapLayerAction  # dirty hack since SIP seems to introduce the flags in module
+QgsMapLayerAction.Flags.baseClass = QgsMapLayerAction
+Flags = QgsMapLayerAction  # dirty hack since SIP seems to introduce the flags in module
 QgsMapToolIdentify.IdentifyMode.baseClass = QgsMapToolIdentify
+QgsMapToolIdentify.LayerType.baseClass = QgsMapToolIdentify
+LayerType = QgsMapToolIdentify  # dirty hack since SIP seems to introduce the flags in module
 QgsAttributeTableFilterModel.FilterMode.baseClass = QgsAttributeTableFilterModel
 QgsAttributeTableFilterModel.ColumnType.baseClass = QgsAttributeTableFilterModel
 QgsDualView.ViewMode.baseClass = QgsDualView

scripts/sipify.pl

@@ -612,10 +612,11 @@ sub detect_non_method_member{
         }
         next;
     }
-    if ($LINE =~ m/Q_ENUM\(\s*(\w+)\s*\)/ ){
+    if ($LINE =~ m/Q_(ENUM|FLAG)\(\s*(\w+)\s*\)/ ){
         if ($LINE !~ m/SIP_SKIP/){
-            my $enum_helper = "$ACTUAL_CLASS.$1.baseClass = $ACTUAL_CLASS";
-            dbg_info("Q_ENUM $enum_helper");
+            my $is_flag = $1 eq 'FLAG' ? 1 : 0;
+            my $enum_helper = "$ACTUAL_CLASS.$2.baseClass = $ACTUAL_CLASS";
+            dbg_info("Q_ENUM/Q_FLAG $enum_helper");
             if ($python_output ne ''){
                 my $pl;
                 open(FH, '+<', $python_output) or die $!;
@@ -626,6 +627,11 @@ sub detect_non_method_member{
                     }
                 }
                 if ($enum_helper ne ''){
+                  if ($is_flag == 1){
+                      # SIP seems to introduce the flags in the module rather than in the class itself
+                      # as a dirty hack, inject directly in module, hopefully we don't have flags with the same name....
+                      $enum_helper .= "\n$2 = $ACTUAL_CLASS  # dirty hack since SIP seems to introduce the flags in module";
+                  }
                     print FH "$enum_helper\n";
                 }
                 close(FH);

src/core/qgssettings.h

@@ -227,6 +227,7 @@ class CORE_EXPORT QgsSettings : public QObject
      * Hence if the setting value is incorrect, the given default value is returned.
      * This tries first with setting as a string (as the enum) and then as an integer value.
      * \note The enum needs to be declared with Q_ENUM, and flags with Q_FLAG (not Q_FLAGS).
+     * \note for Python bindings, a custom implementation is achieved in Python directly
      * \see setEnumValue
      * \see flagValue
      */
@@ -304,6 +305,7 @@ class CORE_EXPORT QgsSettings : public QObject
      * Hence if the setting value is incorrect, the given default value is returned.
      * This tries first with setting as a string (using a byte array) and then as an integer value.
      * \note The flag needs to be declared with Q_FLAG (not Q_FLAGS).
+     * \note for Python bindings, a custom implementation is achieved in Python directly.
      * \see setFlagValue
      * \see enumValue
      */

tests/src/python/test_core_additions.py

@@ -24,16 +24,19 @@
 
 class TestCoreAdditions(unittest.TestCase):
 
-    def testEnum(self):
+    def testMetaEnum(self):
         me = metaEnumFromValue(QgsTolerance.Pixels)
         self.assertIsNotNone(me)
         self.assertEqual(me.valueToKey(QgsTolerance.Pixels), 'Pixels')
 
         # if using same variable twice (e.g. me = me2), this seg faults
-        me2 = metaEnumFromValue(QgsTolerance.Pixels, True, QgsTolerance)
+        me2 = metaEnumFromValue(QgsTolerance.Pixels, QgsTolerance)
         self.assertIsNotNone(me)
         self.assertEqual(me2.valueToKey(QgsTolerance.Pixels), 'Pixels')
 
+        # do not raise error
+        self.assertIsNone(metaEnumFromValue(1, QgsTolerance, False))
+
         # do not provide an int
         with self.assertRaises(TypeError):
             metaEnumFromValue(1)

tests/src/python/test_qgssettings.py

@@ -12,7 +12,7 @@
 
 import os
 import tempfile
-from qgis.core import (QgsSettings,)
+from qgis.core import QgsSettings, QgsTolerance, QgsMapLayerProxyModel
 from qgis.testing import start_app, unittest
 from qgis.PyQt.QtCore import QSettings
 
@@ -391,6 +391,23 @@ def test_remove(self):
         self.settings.remove('testQgisSettings/temp', section=QgsSettings.Core)
         self.assertEqual(self.settings.value('testqQgisSettings/temp', section=QgsSettings.Core), None)
 
+    def test_enumValue(self):
+        self.settings.setValue('enum', 'LayerUnits')
+        self.assertEqual(self.settings.enumValue('enum', QgsTolerance.Pixels), QgsTolerance.LayerUnits)
+        self.settings.setValue('enum', 'dummy_setting')
+        self.assertEqual(self.settings.enumValue('enum', QgsTolerance.Pixels), QgsTolerance.Pixels)
+        self.assertEqual(type(self.settings.enumValue('enum', QgsTolerance.Pixels)), QgsTolerance.UnitType)
+
+    def test_flagValue(self):
+        pointAndLine = QgsMapLayerProxyModel.Filters(QgsMapLayerProxyModel.PointLayer | QgsMapLayerProxyModel.LineLayer)
+        pointAndPolygon = QgsMapLayerProxyModel.Filters(QgsMapLayerProxyModel.PointLayer | QgsMapLayerProxyModel.PolygonLayer)
+
+        self.settings.setValue('flag', 'PointLayer|PolygonLayer')
+        self.assertEqual(self.settings.flagValue('flag', pointAndLine), pointAndPolygon)
+        self.settings.setValue('flag', 'dummy_setting')
+        self.assertEqual(self.settings.flagValue('flag', pointAndLine), pointAndLine)
+        self.assertEqual(type(self.settings.flagValue('enum', pointAndLine)), QgsMapLayerProxyModel.Filters)
+
 
 if __name__ == '__main__':
     unittest.main()