QAbstractItemModelTester

The QAbstractItemModelTester class helps testing QAbstractItemModel subclasses. More…

Synopsis

Functions

• def failureReportingMode ()

• def model ()

Detailed Description

The QAbstractItemModelTester class is a utility class to test item models.

When implementing an item model (that is, a concrete QAbstractItemModel subclass) one must abide to a very strict set of rules that ensure consistency for users of the model (views, proxy models, and so on).

For instance, for a given index, a model’s reimplementation of hasChildren() must be consistent with the values returned by rowCount() and columnCount() .

QAbstractItemModelTester helps catching the most common errors in custom item model classes. By performing a series of tests, it will try to check that the model status is consistent at all times. The tests will be repeated automatically every time the model is modified.

QAbstractItemModelTester employs non-destructive tests, which typically consist in reading data and metadata out of a given item model. QAbstractItemModelTester will also attempt illegal modifications of the model. In models which are properly implemented, such attempts should be rejected, and no data should be changed as a consequence.

Usage

Using QAbstractItemModelTester is straightforward. In a test case it is sufficient to create an instance, passing the model that needs to be tested to the constructor:

MyModel *modelToBeTested = ...;
auto tester = new QAbstractItemModelTester(modelToBeTested);

QAbstractItemModelTester will report testing failures through the Qt Test logging mechanisms.

It is also possible to use QAbstractItemModelTester outside of a test case. For instance, it may be useful to test an item model used by an application without the need of building an explicit unit test for such a model (which might be challenging). In order to use QAbstractItemModelTester outside of a test case, pass one of the QAbstractItemModelTester::FailureReportingMode enumerators to its constructor, therefore specifying how failures should be logged.

QAbstractItemModelTester may also report additional debugging information as logging messages under the qt.modeltest logging category. Such debug logging is disabled by default; refer to the QLoggingCategory documentation to learn how to enable it.

Note

While QAbstractItemModelTester is a valid help for development and testing of custom item models, it does not (and cannot) catch all possible problems in QAbstractItemModel subclasses. Notably, it will never perform meaningful destructive testing of a model, which must be therefore tested separately.

See also

Model/View Programming QAbstractItemModel

class PySide2.QtTest.QAbstractItemModelTester(model, mode[, parent=None])

PySide2.QtTest.QAbstractItemModelTester(model[, parent=None])

param parent:

PySide2.QtCore.QObject

param model:

PySide2.QtCore.QAbstractItemModel

param mode:

FailureReportingMode

Creates a model tester instance, with the given parent , that will test the model model , using the specified mode to report test failures.

See also

FailureReportingMode

Creates a model tester instance, with the given parent , that will test the model model .

PySide2.QtTest.QAbstractItemModelTester.FailureReportingMode

This enumeration specifies how QAbstractItemModelTester should report a failure when it tests a QAbstractItemModel subclass.

Constant	Description
QAbstractItemModelTester.FailureReportingMode.QtTest	The failures will be reported through QtTest ‘s logging mechanism.
QAbstractItemModelTester.FailureReportingMode.Warning	The failures will be reported as warning messages in the qt.modeltest logging category.
QAbstractItemModelTester.FailureReportingMode.Fatal	A failure will cause immediate and abnormal program termination. The reason for the failure will be reported using qFatal().

PySide2.QtTest.QAbstractItemModelTester.failureReportingMode()

Return type:

FailureReportingMode

Returns the mode that this instancing is using to report test failures.

See also

FailureReportingMode

PySide2.QtTest.QAbstractItemModelTester.model()

Return type:

PySide2.QtCore.QAbstractItemModel

Returns the model that this instance is testing.