add test_widgets module with DragDropLineEdit tests

Author: chrissimpkins

tests/test_widgets.py

@@ -0,0 +1,24 @@
+import pytest
+
+from PyQt5.QtWidgets import QWidget
+from PyQt5.QtTest import QTest
+
+from slice.ui.widgets import DragDropLineEdit
+
+
+def test_drag_drop_line_edit(qtbot):
+    widget1 = QWidget()
+    widget2 = DragDropLineEdit(widget1)
+    # placeholder text
+    assert (
+        widget2.placeholderText() == "Drop a variable font here or click the Open button"
+    )
+    assert widget2.isEnabled() is True
+    # accepts drops
+    assert widget2.acceptDrops() is True
+    # uses a clear button
+    assert widget2.isClearButtonEnabled() is True
+    # test text entry
+    assert widget2.text() == ""
+    QTest.keyClicks(widget2, "test")
+    assert widget2.text() == "test"