Add tests for traceback on eval error and "" on eval success

qgis · Feb 18, 2022 · 24c8014 · 24c8014
1 parent 1877b36
commit 24c8014
Showing 1 changed file with 24 additions and 0 deletions.
diff --git a/tests/src/python/test_qgsexpression.py b/tests/src/python/test_qgsexpression.py
@@ -70,6 +70,10 @@ def null_mean(values, feature, parent):
         vals = [val for val in values if val != NULL]
         return sum(vals) / len(vals)
 
+    @qgsfunction(group='testing', register=False)
+    def raise_exception(feature, parent):
+        foo  # an undefined variable
+
     def tearDown(self):
         QgsExpression.unregisterFunction('testfun')
 
@@ -290,6 +294,26 @@ def testReferencedAttributeIndexesNonExistingField(self):
         e.setExpression("foo = 1")
         self.assertTrue(e.isValid())
         self.assertEqual(len(e.referencedAttributeIndexes(QgsFields())), 0)
+
+    def testSuccessfulEvaluationReturnsNoEvalErrorString(self):
+        exp = QgsExpression("True is False")  # the result does not matter
+        self.assertEqual(exp.evalErrorString(), "")
+
+    def testExceptionDuringEvalReturnsTraceback(self):
+        QgsExpression.registerFunction(self.raise_exception)
+        exp = QgsExpression('raise_exception()')
+        result = exp.evaluate()
+        # The file paths and line offsets are dynamic
+        regex = (
+            "name 'foo' is not defined:<pre>Traceback \\(most recent call last\\):\n"
+            "  File \".*qgsfunction.py\", line [0-9]+, in func\n"
+            "    return self.function\\(\\*values\\)\n"
+            "  File \".*test_qgsexpression.py\", line [0-9]+, in raise_exception\n"
+            "    foo  # an undefined variable\n"
+            "NameError: name \'foo\' is not defined"
+            "\n</pre>"
+        )
+        self.assertRegex(exp.evalErrorString(), regex)
 
 
 if __name__ == "__main__":