use pybridge to capture stderr for transcript tests

cmd2/transcript.py

@@ -23,6 +23,7 @@ class is used in cmd2.py::run_transcript_tests()
 
 from . import (
     ansi,
+    py_bridge,
     utils,
 )
 
@@ -75,6 +76,7 @@ def _test_transcript(self, fname: str, transcript: Iterator[str]) -> None:
         if self.cmdapp is None:
             return
 
+        pybridge = py_bridge.PyBridge(self.cmdapp)
         line_num = 0
         finished = False
         line = ansi.strip_style(next(transcript))
@@ -105,8 +107,9 @@ def _test_transcript(self, fname: str, transcript: Iterator[str]) -> None:
                 line_num += 1
             command = ''.join(command_parts)
             # Send the command into the application and capture the resulting output
-            stop = self.cmdapp.onecmd_plus_hooks(command)
-            result = self.cmdapp.stdout.read()
+            cmd_result = pybridge(command)
+            stop = cmd_result.stop
+            result = cmd_result.stderr + cmd_result.stdout
             stop_msg = 'Command indicated application should quit, but more commands in transcript'
             # Read the expected result from transcript
             if ansi.strip_style(line).startswith(self.cmdapp.visible_prompt):

tests/test_transcript.py

@@ -92,6 +92,14 @@ def do_nothing(self, statement):
         """Do nothing and output nothing"""
         pass
 
+    def do_say_warn(self, statement):
+        """Do pwarn message"""
+        self.pwarning("speak a warning: " + statement)
+
+    def do_say_error(self, statement):
+        """Do perror message"""
+        self.perror("speak an error: " + statement)
+
     def do_keyboard_interrupt(self, _):
         raise KeyboardInterrupt('Interrupting this command')
 
@@ -120,6 +128,7 @@ def test_commands_at_invocation():
         ('multiline_regex.txt', False),
         ('no_output.txt', False),
         ('no_output_last.txt', False),
+        ('pwarn_perror.txt', False),
         ('regex_set.txt', False),
         ('singleslash.txt', False),
         ('slashes_escaped.txt', False),
@@ -332,3 +341,30 @@ def test_transcript_no_file(request, capsys):
     expected = 'No test files found - nothing to test\n'
     _, err = capsys.readouterr()
     assert err == expected
+
+
+def test_transcript_bad_cmd(request, capsys):
+    # Get location of the transcript
+    test_dir = os.path.dirname(request.module.__file__)
+    transcript_file = os.path.join(test_dir, 'transcripts', 'fail_no_command.txt')
+
+    # Need to patch sys.argv so cmd2 doesn't think it was called with
+    # arguments equal to the py.test args
+    testargs = ['prog', '-t', transcript_file]
+    with mock.patch.object(sys, 'argv', testargs):
+        # Create a cmd2.Cmd() instance and make sure basic settings are
+        # like we want for test
+        app = CmdLineApp()
+
+    app.feedback_to_output = False
+
+    # Run the command loop
+    sys_exit_code = app.cmdloop()
+    assert sys_exit_code != 0
+    expected_start = "File "
+    expected_middle = "youdontsay is not a recognized command, alias, or macro"
+    expected_end = "s\n\nFAILED (failures=1)\n\n"
+    _, err = capsys.readouterr()
+    assert err.startswith(expected_start)
+    assert expected_middle in err
+    assert err.endswith(expected_end)

tests/transcripts/fail_no_command.txt

@@ -0,0 +1,4 @@
+# This is an example of a transcript test which will fail due to nonexistant command
+
+(Cmd) youdontsay -r 3 -s yabba dabba do
+foo bar baz

tests/transcripts/pwarn_perror.txt

@@ -0,0 +1,8 @@
+# ensure the transcript catches output to perror and pwarn from a command
+
+(Cmd) say_warn something
+speak a warning: something
+(Cmd) say_error something
+speak an error: something
+(Cmd) say something else
+something else