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  1. Qt for Python
  2. PYSIDE-1428

Signal does not throw an exception when an incorrect argument is used

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    • Icon: Bug Bug
    • Resolution: Unresolved
    • Icon: P2: Important P2: Important
    • None
    • 5.15.1
    • PySide
    • None
    • All

      When an argument that does not comply with the signature of the signal is used then no exceptions are thrown and it seems that it uses default arguments since in the case that the signature is a string an empty string is sent, and when it is an integer it is sends a 0, generating a silent error that is difficult to track.

       MRE

      import sys

from PySide2.QtCore import QCoreApplication, QObject, Signal, QTimer


class Foo(QObject):
    str_sig = Signal(str)
    int_sig = Signal(int)


class Bar(QObject):
    def bar_slot(self, val):
        print(val)


if __name__ == "__main__":
    app = QCoreApplication(sys.argv)

    foo = Foo()

    bar = Bar()

    foo.str_sig.connect(bar.bar_slot)
    foo.int_sig.connect(bar.bar_slot)

    foo.str_sig.emit(10)
    foo.int_sig.emit("fff")

    QTimer.singleShot(1000, QCoreApplication.quit)

    sys.exit(app.exec_())

      Output:

      
0

      Instead in pyqt5 a TypeError exception is thrown.

        For Gerrit Dashboard: PYSIDE-1428
        # Subject Branch Project Status CR V
        348889,7 signal: warn when wrong emit arg type is used dev pyside/pyside-setup Status: NEW -1 0

            crmaurei Cristian Maureira-Fredes
            eyllanesc Edwin Christian Yllanes Cucho
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              Created:
              Updated:

                There is 1 open Gerrit change