feat(bec_spin_box): double spin box with setting inside for defining decimals

tests/unit_tests/test_decimal_spin_box.py

@@ -0,0 +1,68 @@
+# pylint: disable=missing-function-docstring, missing-module-docstring, unused-import
+import pytest
+from qtpy.QtCore import Qt
+from qtpy.QtWidgets import QInputDialog
+
+from bec_widgets.widgets.utility.spinbox.decimal_spinbox import BECSpinBox
+
+
+@pytest.fixture
+def spinbox_fixture(qtbot):
+    widget = BECSpinBox()
+    qtbot.addWidget(widget)
+    qtbot.waitExposed(widget)
+    yield widget
+
+
+def test_spinbox_initial_values(spinbox_fixture):
+    """
+    Test the default properties of the BECSpinBox.
+    """
+    spinbox = spinbox_fixture
+    assert spinbox.decimals() == 2
+    assert spinbox.minimum() == -2147483647
+    assert spinbox.maximum() == 2147483647
+    assert spinbox.setting_button is not None
+
+
+def test_change_decimals_ui(spinbox_fixture, monkeypatch, qtbot):
+    """
+    Test that clicking on the setting button triggers the QInputDialog to change decimals.
+    We'll simulate a user entering a new decimals value in the dialog.
+    """
+    spinbox = spinbox_fixture
+
+    def mock_get_int(*args, **kwargs):
+        return (5, True)
+
+    monkeypatch.setattr(QInputDialog, "getInt", mock_get_int)
+    assert spinbox.decimals() == 2
+
+    qtbot.mouseClick(spinbox.setting_button, Qt.LeftButton)
+    assert spinbox.decimals() == 5
+
+
+def test_change_decimals_cancel(spinbox_fixture, monkeypatch, qtbot):
+    """
+    Test that if the user cancels the decimals dialog, the decimals do not change.
+    """
+    spinbox = spinbox_fixture
+
+    def mock_get_int(*args, **kwargs):
+        return (0, False)
+
+    monkeypatch.setattr(QInputDialog, "getInt", mock_get_int)
+
+    old_decimals = spinbox.decimals()
+    qtbot.mouseClick(spinbox.setting_button, Qt.LeftButton)
+    assert spinbox.decimals() == old_decimals
+
+
+def test_spinbox_value_change(spinbox_fixture):
+    """
+    Test that the spinbox accepts user input and updates its value accordingly.
+    """
+    spinbox = spinbox_fixture
+    assert spinbox.value() == 0.0
+    spinbox.setValue(123.456)
+    assert spinbox.value() == 123.46