test_cli: make it work even if the test is called interactively

rather "work" (mind the quotes): If pyinquirer is working and this was
called "bare metal" (i.e., not via `pytest`), the `browse` tool
stopped to ask the user for input. Since this is undesireable for a
unit test, we now mock `sys.stdout.isatty()` to always return `False`.

Signed-off-by: Andreas Lauser <[email protected]>
Signed-off-by: Alexander Walz <[email protected]>

tests/test_cli.py

@@ -3,6 +3,7 @@
 import unittest
 from argparse import Namespace
 from typing import List, Optional
+from unittest.mock import MagicMock, patch
 
 import odxtools.cli.compare as compare
 import odxtools.cli.decode as decode
@@ -131,7 +132,10 @@ def test_compare_tool(self) -> None:
         UtilFunctions.run_compare_tool(ecu_variants=["somersault_lazy", "somersault_assiduous"])
 
     @unittest.skipIf(browse_import_failed, "importing the browse tool failed")
-    def test_browse_tool(self) -> None:
+    # browse is an interactive tool, so we need to mock a few
+    # functions to make PyInquirer reliably bail out
+    @patch("sys.stdout.isatty", return_value=False)
+    def test_browse_tool(self, pi_prompt: MagicMock) -> None:
         browse_args = Namespace(pdx_file="./examples/somersault.pdx")
         with self.assertRaises(SystemError):
             # browse can only be run interactively