Add test to ensure style has not been initialized when running

qgis_process

tests/src/python/test_qgsprocessexecutable_pt2.py

@@ -340,6 +340,16 @@ class TestQgsProcessExecutablePt2(unittest.TestCase):
         self.assertEqual(res['algorithm_details']['id'], 'native:buffer')
         self.assertEqual(res['inputs']['DISTANCE'], {'field': 'fid', 'type': 'data_defined'})
 
+    def testStartupOptimisationsStyleLazyInitialized(self):
+        """
+        Ensure that the costly QgsStyle.defaultStyle() initialization is NOT
+        performed by default when running qgis_process commands
+        """
+        rc, output, err = self.run_process(['run', TEST_DATA_DIR + '/report_style_initialization_status.py'])
+        self.assertFalse(self._strip_ignorable_errors(err))
+        self.assertEqual(rc, 0)
+        self.assertIn('IS_INITIALIZED:	false', output)
+
 
 if __name__ == '__main__':
     # look for qgis bin path

tests/testdata/report_style_initialization_status.py

@@ -0,0 +1,43 @@
+"""
+***************************************************************************
+*                                                                         *
+*   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 qgis.core import (
+    QgsStyle,
+    QgsProcessingAlgorithm,
+    QgsProcessingOutputBoolean,
+)
+
+
+class CheckStyleInitializationStatus(QgsProcessingAlgorithm):
+    IS_INITIALIZED = 'IS_INITIALIZED'
+
+    def createInstance(self):
+        return CheckStyleInitializationStatus()
+
+    def name(self):
+        return 'checkstyleinitstatus'
+
+    def displayName(self):
+        return 'Check style initialization status'
+
+    def shortDescription(self):
+        return 'Checks style initialization status'
+
+    def initAlgorithm(self, config=None):
+        self.addOutput(
+            QgsProcessingOutputBoolean(
+                self.IS_INITIALIZED,
+                'Style is initialized'
+            )
+        )
+
+    def processAlgorithm(self, parameters, context, feedback):
+        return {self.IS_INITIALIZED: QgsStyle.defaultStyle(False).isInitialized()}