--- a/eric6/UI/DiffDialog.py	Tue Sep 24 18:46:24 2019 +0200
+++ b/eric6/UI/DiffDialog.py	Tue Sep 24 19:08:10 2019 +0200
@@ -446,8 +446,10 @@
         """
         Private slot to enable/disable the Compare button.
         """
-        if not self.file1Picker.text() or \
-           not self.file2Picker.text():
+        if (
+            not self.file1Picker.text() or
+            not self.file2Picker.text()
+        ):
             self.diffButton.setEnabled(False)
         else:
             self.diffButton.setEnabled(True)