QTableView no longer showing rows since update to 5.7.1 - pyqt5

Question

I recently updated from PyQt 5.7.0 to 5.7.1 and code that worked correctly prior to the update stopped working correctly. So, either my code was always wrong but PyQt5 allowed it to work, or a bug was introduced in PyQt 5.7.1.
I have a custom table view that inherits from QTableView using a custom model that inherits from QAbstractTableModel. When new rows are added to the model, they are not visible in the table view. In fact, no rows ever become visible. Through some debugging, I have validated that the number of rows is changing as expected in my derived model class.
import sys
from PyQt5.QtCore import *
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
import PyQt5.Qt
class JobTableModel(QAbstractTableModel):
def __init__(self, data, parent):
super(JobTableModel, self).__init__()
assert isinstance(parent, QTableView), "'parent' is not a QTableView object"
self._parent = parent
self._data = data
self._rows = 0
self._updateModel()
# end constructor
def updateRows(self, rows):
self.layoutAboutToBeChanged.emit()
self._rows = rows
self.layoutChanged.emit()
# end updateRows
def _updateModel(self):
# Only update rows that are visible to the user
# Note: self._parent is a QTableView
minRow = self._parent.rowAt(0)
if minRow >= 0:
maxRow = self._parent.rowAt(self._parent.height())
if maxRow < 0: maxRow = self._rows - 1
for row in range(minRow, maxRow + 1):
self.dataChanged.emit(self.index(row, 0), self.index(row, self.columnCount(None) - 1))
QTimer.singleShot(490, self._updateModel)
# end _updateModel
def headerData(self, section, orientation, role):
if role == Qt.DisplayRole and orientation == Qt.Horizontal:
return str(section)
#
# end headerData
def rowCount(self, modelIndex):
return self._rows
# end rowCount
def columnCount(self, modelIndex):
return 8 # always the same number of columns
# end columnCount
def data(self, index, role):
if not index.isValid(): return None
if role == Qt.DisplayRole: return '{0}, {1}'.format(index.row(), index.column())
return None
# end data
class JobTableView(QTableView):
def __init__(self, data, parent):
super(JobTableView, self).__init__(parent)
self.setModel(JobTableModel(data, self))
self.setAlternatingRowColors(True)
self.setWordWrap(False)
self.setVerticalScrollBarPolicy(Qt.ScrollBarAlwaysOn)
self.verticalHeader().setVisible(False)
self.verticalHeader().setDefaultSectionSize(23)
self.setSelectionBehavior(QAbstractItemView.SelectRows)
self.setEditTriggers(QAbstractItemView.NoEditTriggers)
if __name__ == '__main__':
app = QApplication(sys.argv)
tv = JobTableView(None, None)
tv.show()
tv.model().updateRows(1)
app.exec_()

Answer 1

I ran the test case using PyQt-5.7, PyQt-5.7.1 and PyQt-5.7.2.dev1701131704 (built with SIP-4.19.1.dev1701101411). The problem is reproducible in PyQt-5.7.1, but not in the other two versions. So, as was suggested in the comments, there is a bug in PyQt-5.7.1 which has already been fixed in the latest snapshots.