[tests] Add test for unloading Expression Functions from projects (on project close) and reloading user ones, specifically to restore overwritten user functions when opening a project with expressions inside

.gitignore

@@ -91,6 +91,8 @@ tests/testdata/raster/band3_float32_noct_epsg4326.tif.aux.xml
 tests/testdata/raster/band3_int16_noct_epsg4326.tif.aux.xml
 tests/testdata/tenbytenraster.asc.aux.xml
 tests/testdata/test_plugin_path/plugin_started.txt
+tests/testdata/test_qgis_config_path/profiles/default/*
+!tests/testdata/test_qgis_config_path/profiles/default/python
 tests/testdata/widget_config.qlr
 tests/testdata/zip/testtar.tgz.properties
 venv

src/app/qgisapp.h

@@ -2759,6 +2759,7 @@ class APP_EXPORT QgisApp : public QMainWindow, private Ui::MainWindow
 
     friend class TestQgisAppPython;
     friend class TestQgisApp;
+    friend class TestQgsProjectExpressions;
     friend class QgisAppInterface;
     friend class QgsAppScreenShots;
 };

tests/src/app/CMakeLists.txt

@@ -63,6 +63,7 @@ endif()
 
 if (WITH_BINDINGS)
   set(TESTS ${TESTS} testqgisapppython.cpp)
+  set(TESTS ${TESTS} testqgsprojectexpressions.cpp)
 endif()
 
 foreach(TESTSRC ${TESTS})

tests/src/app/testqgsprojectexpressions.cpp

@@ -0,0 +1,109 @@
+/***************************************************************************
+     testqgsprojectexpressions.cpp
+     --------------------
+    Date                 : Aug 2024
+    Copyright            : (C) 2024 by Germán Carrillo
+    Email                : german at opengis dot 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.                                   *
+ *                                                                         *
+ ***************************************************************************/
+#include <QApplication>
+#include <QObject>
+#include <QSplashScreen>
+#include <QString>
+#include <QStringList>
+#include "qgstest.h"
+
+#include <qgisapp.h>
+#include <qgsapplication.h>
+
+/**
+ * \ingroup UnitTests
+ * This is a unit test for the Save Python Expression in project support.
+ */
+class TestQgsProjectExpressions : public QObject
+{
+    Q_OBJECT
+
+  public:
+    TestQgsProjectExpressions();
+
+  private slots:
+    void initTestCase();// will be called before the first testfunction is executed.
+    void cleanupTestCase();// will be called after the last testfunction was executed.
+
+    void projectExpressions();
+
+  private:
+    QgisApp *mQgisApp = nullptr;
+};
+
+TestQgsProjectExpressions::TestQgsProjectExpressions() = default;
+
+//runs before all tests
+void TestQgsProjectExpressions::initTestCase()
+{
+  const QByteArray configPath = QByteArray( TEST_DATA_DIR ) + "/test_qgis_config_path";
+  qputenv( "QGIS_CUSTOM_CONFIG_PATH", configPath );
+
+  // Set up the QgsSettings environment
+  QCoreApplication::setOrganizationName( QStringLiteral( "QGIS" ) );
+  QCoreApplication::setOrganizationDomain( QStringLiteral( "qgis.org" ) );
+  QCoreApplication::setApplicationName( QStringLiteral( "QGIS-TEST" ) );
+
+  qDebug() << "TestQgsProjectExpressions::initTestCase()";
+  // init QGIS's paths - true means that all path will be inited from prefix
+  QgsApplication::init();
+  QgsApplication::initQgis();
+  mQgisApp = new QgisApp();
+  mQgisApp->loadPythonSupport();
+}
+
+//runs after all tests
+void TestQgsProjectExpressions::cleanupTestCase()
+{
+  QgsApplication::exitQgis();
+}
+
+void TestQgsProjectExpressions::projectExpressions()
+{
+  const int count_before_project = QgsExpression::functionCount();
+  QVERIFY( QgsExpression::functionIndex( QStringLiteral( "mychoice" ) ) != -1 ); // User expression loaded
+
+  const QString myExpression = QStringLiteral( "mychoice(1, 2)" );
+  QgsExpression exp( QStringLiteral( "mychoice(1, 2)" ) );
+  QCOMPARE( exp.evaluate().toInt(), 1 );
+
+  // Load expressions from project
+  // Project registers 2 functions: mychoice (overwriting it) and myprojectfunction
+  const QByteArray projectPath = QByteArray( TEST_DATA_DIR ) + "/projects/test_project_functions.qgz";
+  QgsProject::instance()->read( projectPath );
+  QCOMPARE( QgsExpression::functionIndex( QStringLiteral( "myprojectfunction" ) ), -1 );
+  QgsExpression::loadFunctionsFromProject();
+  QVERIFY( QgsExpression::functionIndex( QStringLiteral( "myprojectfunction" ) ) != -1 );
+  QVERIFY( QgsExpression::functionIndex( QStringLiteral( "mychoice" ) ) != -1 ); // Overwritten function
+  const int count_project_loaded = QgsExpression::functionCount();
+
+  QCOMPARE( count_project_loaded - count_before_project, 1 ); // myprojectfunction
+
+  exp = myExpression; // Re-parse it
+  QCOMPARE( exp.evaluate().toInt(), 2 );  // Different result because now it's from project
+
+  // Unload expressions from project, reload user ones
+  QgsExpression::cleanFunctionsFromProject();
+  const int count_project_unloaded = QgsExpression::functionCount();
+  QCOMPARE( count_before_project, count_project_unloaded ); // myprojectfunction is gone
+
+  QCOMPARE( QgsExpression::functionIndex( QStringLiteral( "myprojectfunction" ) ), -1 );
+  exp = myExpression; // Re-parse it
+  QCOMPARE( exp.evaluate().toInt(), 1 ); // Original result, coming from user function
+}
+
+
+QGSTEST_MAIN( TestQgsProjectExpressions )
+#include "testqgsprojectexpressions.moc"

tests/testdata/test_qgis_config_path/profiles/default/python/expressions/test.py

@@ -0,0 +1,6 @@
+from qgis.core import qgsfunction
+
+
+@qgsfunction(group='Custom', referenced_columns=[])
+def mychoice(value1, value2):
+    return value1

tests/testdata/test_qgis_config_path/profiles/default/python/expressions/test2.py

@@ -0,0 +1,6 @@
+from qgis.core import qgsfunction
+
+
+@qgsfunction(group='Custom', referenced_columns=[])
+def mychoice2(value1, value2):
+    return value1 + value2