.. _pysideapi2:

|project| Considerations
=========================

API Changes
-----------

One of the goals of |pymodname| is to be API compatible with PyQt5,
with certain exceptions.

The latest considerations and known issues will be also reported
in the `wiki <https://wiki.qt.io/Qt_for_Python/Considerations>`_.

__hash__() function return value
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The hash value returned for the classes :class:`PySide2.QtCore.QDate`,
:class:`PySide2.QtCore.QDateTime`, :class:`PySide2.QtCore.QTime`, :class:`PySide2.QtCore.QUrl`
will be based on their string representations, thus objects with the same value will produce the
same hash.


QString
~~~~~~~~

Methods and functions that change the contents of a QString argument were modified to receive an
immutable Python Unicode (or str) and return another Python Unicode/str as the modified string.

The following methods had their return types modified this way:

**Classes:** QAbstractSpinBox, QDateTimeEdit, QDoubleSpinBox, QSpinBox, QValidator

* ``fixup(string): string``
* ``validate(string, int): [QValidator.State, string, int]``

**Classes:** QDoubleValidator, QIntValidator, QRegExpValidator

* ``validate(string, int): [QValidator.State, string, int]``

**Class:** QClipboard

* ``text(string, QClipboard.Mode mode=QClipboard.Clipboard): [string, string]``

**Class:** QFileDialog

Instead of ``getOpenFileNameAndFilter()``, ``getOpenFileNamesAndFilter()`` and
``getSaveFileNameAndFilter()`` like PyQt does, PySide has modified the original methods to return
a tuple.

* ``getOpenFileName(QWidget parent=None, str caption=None, str dir=None, str filter=None, QFileDialog.Options options=0): [string, filter]``
* ``getOpenFileNames(QWidget parent=None, str caption=None, str dir=None, str filter=None, QFileDialog.Options options=0): [list(string), filter]``
* ``getSaveFileName(QWidget parent=None, str caption=None, str dir=None, str filter=None, QFileDialog.Options options=0): [string, filter]``

**Class:** QWebPage

* ``javaScriptPrompt(QWebFrame, string, string): [bool, string]``

**Classes:** QFontMetrics and QFontMetricsF

They had two new methods added. Both take a string of one character and convert to a QChar
(to call the C++ counterpart):

* ``widthChar(string)``
* ``boundingRectChar(string)``


QTextStream
~~~~~~~~~~~

Inside this class some renames were applied to avoid clashes with native Python functions.
They are: ``bin_()``, ``hex_()`` and ``oct_()``.
The only modification was the addition of '_' character.


QVariant
~~~~~~~~

As ``QVariant`` was removed, any function expecting it can receive any Python object (``None`` is
an invalid ``QVariant``).
The same rule is valid when returning something: the returned ``QVariant`` will be converted to
the its original Python object type.

When a method expects a ``QVariant::Type`` the programmer can use a string (the type name) or the
type itself.
