Set show_internal_console_if_traceback to True when DEV mode or testing is activated.

Author: rlaverde

Diff for: spyder/app/mainwindow.py

@@ -432,6 +432,11 @@ def signal_handler(signum, frame=None):
         if options.window_title is not None:
             title += ' -- ' + options.window_title
 
+        if DEV or DEBUG or PYTEST:
+            # Show errors in internal console when developing or testing.
+            CONF.set('main', 'show_internal_console_if_traceback', True)
+
+
         self.base_title = title
         self.update_window_title()
         resample = os.name != 'nt'